Are Black Holes in Our Galaxy Composed of Dark Matter? Exploring the Connection

Posted on February 19, 2026 by Igor Mitreski

Polarized Image of Sagittarius A*

Credit: EHT Collaboration

At the galactic center lies the enigmatic supermassive black hole, Sagittarius A*. Some researchers propose that this may not be a black hole at all, but rather clusters of dark matter.

Dark matter, which comprises about 85% of the universe’s matter, does not interact with light or normal matter outside of gravitational forces. Despite its significance, our understanding of dark matter is limited. As Valentina Crespi from the National University of La Plata (UNLP) notes, “While we know dark matter exists at the galaxy’s edge, the core remains a mystery.”

Crespi and her team developed a model of a galactic nucleus made of dark matter consisting of light particles called fermions. Their findings suggest that fermion dark matter can clump in ways that resemble supermassive black holes from afar.

“From Earth, this scenario appears akin to what one would expect from a black hole; however, a spacecraft could pass through without any issues,” explains Carlos Arguelles, part of the UNLP research team. “Even if you were swallowed by a black hole, you wouldn’t perish; you would pass through safely.”

The researchers base their model on the orbit of a star near Sagittarius A* and a small gas cloud, aligning with observations of galaxy rotation and imagery from the Event Horizon Telescope (EHT) from 2022. This imaging reveals a glowing ring of superheated matter around Sagittarius A*, potentially influenced by a dark matter core.

However, observation support for the dark matter theory does not confirm its validity. Gaston Gillibet from New York University stresses, “While this simple explanation aligns with the evidence, I still believe the central object is likely a black hole.” He emphasizes the necessity of remaining open to all possibilities in this fascinating debate.

Concerns arise regarding the model’s applicability to observations near the event horizon. Shep Doeleman from Harvard University notes that the distinctive spiral pattern of the magnetic field in this region corresponds closely with black hole characteristics.

Moreover, fermion dark matter’s clumping is limited to about 10 million times the Sun’s mass. Although this could explain the majestic size of supermassive black holes, images of M87*—a black hole substantially larger than Sagittarius A*—complicate this theory as M87* closely resembles Sagittarius A* despite its size of approximately 6.5 billion solar masses.

Researchers admit that both dark matter and black hole theories hold equal plausibility. Crespi notes, “While we have enhanced tools today, confirming the nature of these phenomena is still not foolproof.” Achieving the necessary image resolution for this identification would extend far beyond the capabilities of even the next-generation EHT, indicating that definitive answers may be decades away.

If Sagittarius A* is indeed a manifestation of dark matter, it would profoundly impact our understanding of the universe. Fermion dark matter, which current cosmological models do not predict, could revolutionize not only our comprehension of black holes but also our entire cosmic paradigm.

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New Research Unveils Milky Way’s Central Black Hole as a Compact Object of Fermion Dark Matter

Posted on February 6, 2026 by Igor Mitreski

For decades, the movement of stars near the center of our Milky Way galaxy has provided some of the most convincing evidence for the existence of a supermassive black hole. However, Dr. Valentina Crespi from the La Plata Institute of Astrophysics and her colleagues propose an innovative alternative: a compact object composed of self-gravitating fermion dark matter, which could equally explain the observed stellar motions.

A compact object made of self-gravitating fermion dark matter. Image credit: Gemini AI.

The prevailing theory attributes the observational orbits of a group of stars, known as the S stars, to Sagittarius A*, the supposed supermassive black hole at our galaxy’s center, which causes these stars to move at speeds of thousands of kilometers per second.

In a groundbreaking study, Dr. Crespi and her team propose that fermions—a specific type of dark matter made from light elementary particles—can form a distinct cosmic structure that aligns with our current understanding of the Milky Way’s core.

The hypothesis suggests the formation of an ultra-dense core surrounded by a vast, diffuse halo, functioning as a unified structure.

This dense core could replicate the gravitational effects of a black hole, thereby accounting for the orbits of S stars and nearby dusty objects known as G sources.

A vital aspect of this research includes recent data from ESA’s Gaia DR3 mission, which meticulously maps the Milky Way’s outer halo and reveals the orbital patterns of stars and gas far from the center.

The mission has documented a slowdown in the galaxy’s rotation curve, known as Keplerian decay, which can be reconciled with the outer halo of the dark matter model when combined with the standard disk and bulge components of normal matter.

This finding emphasizes significant structural differences, bolstering the validity of the fermion model.

While traditional cold dark matter halos spread in a “power law” fashion, the fermion model predicts a more compact halo structure with a tighter tail.

“This research marks the first instance where a dark matter model effectively connects vastly different scales and explains the orbits of various cosmic bodies, including contemporary rotation curves and central star data,” remarked Carlos Arguelles of the La Plata Astrophysics Institute.

“We are not merely substituting black holes for dark objects. Instead, we propose that supermassive centers and galactic dark matter halos represent two manifestations of a single continuum of matter.”

Importantly, the team’s fermion dark matter model has already undergone rigorous testing.

A recent 2024 survey demonstrated that as the accretion disk illuminates these dense dark matter cores, it produces shadow-like features reminiscent of those captured by the Event Horizon Telescope (EHT) collaboration at Sagittarius A*.

“This point is crucial. Our model not only elucidates stellar orbits and galactic rotation but also aligns with the famous ‘black hole shadow’ image,” stated Crespi.

“A dense dark matter core bends light to such an extent that it forms a central darkness encircled by a bright ring, creating an effect similar to shadows.”

Astronomers performed a statistical comparison of the fermion dark matter model against traditional black hole models.

While current data on internal stars cannot definitively distinguish between the two theories, the dark matter model offers a cohesive framework to elucidate both the galaxy’s center (encompassing the central star and shadow) and the galaxy at large.

“Gathering more precise data from instruments like the GRAVITY interferometer aboard ESO’s Very Large Telescope in Chile, and searching for specific features of the photon ring, an essential characteristic of black holes that are absent in the dark matter nuclear scenario, will be crucial for testing the predictions of this innovative model,” the authors noted.

“The results of these discoveries have the potential to revolutionize our understanding of the fundamental nature of the Milky Way’s enigmatic core.”

The team’s research was published today in Royal Astronomical Society Monthly Notices.

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V. Crespi et al. 2026. Dynamics of S stars and G sources orbiting supermassive compact objects made of fermion dark matter. MNRAS 546 (1): staf1854; doi: 10.1093/mnras/staf1854

Source: www.sci.news

Massive Dark Matter Cloud Detected Near Our Solar System: What’s at Stake?

Posted on February 2, 2026 by Igor Mitreski

Possible Large Clump of Dark Matter Near Our Galaxy

Credit: Alamy

Dark Matter Discovery — Possible Large Clump of Dark Matter Near Our Galaxy

Credit: Alamy

A significant discovery indicates the presence of a gigantic dark matter cloud adjacent to our solar system. These clouds, previously unidentified in the Milky Way, have been detected thanks to precise cosmic clocks known as pulsars.

Current cosmological models propose that galaxies are enveloped in diffuse clouds of dark matter called halos, with smaller subhaloes scattered throughout. However, the elusive nature of dark matter, which neither emits, absorbs, nor reflects light, complicates the detection of these halos and subhalos.

To quantify this dark matter phenomenon, Sukanya Chakrabarti and her research team at the University of Alabama in Huntsville leveraged pairs of rapidly spinning neutron stars known as pulsars. These cosmic clocks emit beams of light at consistent intervals, allowing researchers to measure variations in their trajectories when influenced by large nearby mass.

Given that dark matter interacts with ordinary matter solely through gravity, an adjacent dark matter subhalo would alter the orbit of neighboring pulsars. This is precisely what Chakrabarti and her collaborators identified approximately 3,000 light years from our solar system. “Our observations detected a pair of pulsars whose motions indicate an unexpected gravitational pull from an unseen object,” comments Philip Chan from the University of Wisconsin-Milwaukee.

The research revealed that this gravitational influence originated from an object approximately 60 million times more massive than the Sun and spanning hundreds of light years. After mapping the location against stellar data, no correlations with known celestial bodies were found. If validated, this object could be a unique example of dark matter.

This potential dark matter subhalo could be the only instance of such size in our local galactic vicinity. “There may only be one or two of these large features nearby, depending on dark matter models,” suggests Alice Quillen at the University of Rochester in New York. “Different dark matter theories propose varying distributions of these structures.”

This pursuit is what catalyzed Chakrabarti’s interest in subhalo research. “Our objective is to map as many subhaloes as we can throughout the galaxy, and we’re just beginning to achieve that. Ultimately, we aim to elucidate the nature of dark matter,” she asserts.

However, pulsar binaries are scarce; only 27 instances provide sufficient accuracy for measuring gravitational acceleration. This scarcity explains why this subhalo remained undetected until now. “Given the finite number of pulsars, we are exploring alternative methods to monitor them using a broader array of objects,” states Zhang. If successful, this could be a breakthrough in understanding the true nature of dark matter.

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Source: www.newscientist.com

Webb Telescope Unveils Most Detailed Dark Matter Map to Date

Posted on January 28, 2026 by Igor Mitreski

Utilizing the ultra-sharp images from the NASA/ESA/CSA James Webb Space Telescope, astronomers have successfully crafted a highly detailed, wide-area mass map of the Universe. This groundbreaking map reveals the intricate interweaving of dark matter and ordinary matter, stretching from the filaments of galaxies to the dense clusters. Developed as part of the COSMOS-Web survey, this new map boasts more than double the resolution of previous efforts and delves deeper into the early universe’s evolution.

This web image shows about 800,000 galaxies, overlaid with a dark matter map in blue. Image credit: NASA / STScI / J. DePasquale / A. Pagan.

Dark matter constitutes roughly 85% of the universe’s total matter, yet it’s challenging to detect since it neither emits nor absorbs light, rendering it invisible to standard telescopes.

However, its gravitational influence alters the trajectory of light from far-off galaxies.

By examining subtle distortions in the shapes of numerous distant galaxies, scientists can ascertain how this unseen mass is distributed, irrespective of its nature.

When compared with known luminous structures, researchers can pinpoint the locations of dark matter.

Previous mass maps generated using the NASA/ESA Hubble Space Telescope and other observatories suffered from limited resolution, sensitivity, and area coverage, restricting their views to only the largest cosmic structures.

Dr. Diana Scognamiglio from NASA’s Jet Propulsion Laboratory and her team harnessed Webb’s imaging capabilities to analyze the shapes of approximately 250,000 galaxies, reconstructing the most detailed mass map of a contiguous universe region to date.

“This is the most extensive dark matter map produced in conjunction with Webb, boasting clarity unmatched by any prior dark matter maps from other observatories,” stated Dr. Scognamiglio.

“Previously, we only glimpsed blurred images of dark matter.”

“With Webb’s extraordinary resolution, we can now observe the universe’s invisible framework in unprecedented detail.”

This new map uncovers substantial galaxy clusters along with intricate networks of dark filamentary bridges and low-mass galaxies, too faint or too distant to be spotted by conventional telescopes.

These formations align with major cosmological models, suggesting that galaxies emerge at dense points between the dark matter filaments spreading throughout the universe.

Dr. Gavin Leroy, an astronomer at Durham University, remarked: “By illustrating dark matter with unparalleled precision, our map demonstrates how the unseen elements of the universe shaped visible matter, facilitating the creation of galaxies, stars, and ultimately, life itself.”

“This map highlights the crucial role of dark matter, the universe’s true architect, which gradually organizes the structures we observe through our telescopes.”

Professor Richard Massey of Durham University added, “Wherever normal matter exists in the universe today, dark matter is also present.”

“Every second, billions of dark matter particles pass through your body. They are harmless and continue on their paths unnoticed.”

“However, the entire cloud of dark matter surrounding the Milky Way possesses enough gravity to keep our galaxy intact. Without dark matter, the Milky Way would disintegrate.”

For more information, refer to the published results in this week’s edition of Nature Astronomy.

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D. Scognamiglio et al. Ultra-high resolution map of (dark) matter. Nat Astron published online on January 26, 2026. doi: 10.1038/s41550-025-02763-9

Source: www.sci.news

Unveiling the Ultimate Dark Matter Map: Discovering Unprecedented Cosmic Structures

Posted on January 26, 2026 by Igor Mitreski

Dark Matter Distribution: Hubble vs. James Webb

Credit: Dr. Gavin Leroy/Professor Richard Massey/COSMOS-Webb Collaboration

dark matter distribution — Dark Matter Distribution: Hubble vs. James Webb

Credit: Dr. Gavin Leroy/Professor Richard Massey/COSMOS-Webb Collaboration

In a groundbreaking study, scientists leveraged subtle distortions in the shapes of over 250,000 galaxies to construct the most detailed dark matter map to date, paving the way for insights into some of the universe’s greatest enigmas.

Dark matter, elusive by nature, does not emit any detectable light. Its existence can only be inferred through its gravitational interactions with normal matter. Researchers, including Jacqueline McCreary from Northeastern University, utilized the James Webb Space Telescope (JWST) to map a region of the sky larger than the full moon.

“This high-resolution image depicts the scaffold of a small segment of the universe,” noted McCreary. The new map boasts double the resolution of previous ones created by the Hubble Space Telescope, encompassing structures much farther away.

The researchers studied approximately 250,000 galaxies, noting that their shapes, while interesting, serve primarily as a backdrop for understanding gravitational distortions. As Liliya Williams from the University of Minnesota explained, “These galaxies merely act as the universe’s wallpaper.” The critical component is the way dark matter’s gravitational pull warps the light from these distant galaxies—a phenomenon known as gravitational lensing. The more distorted the shape of these galaxies is from a perfect circle, the greater the amount of dark matter situated between us and them.

By analyzing these optical distortions, the team was able to derive a map illustrating massive galaxy clusters and the cosmic web filaments linking them. Many of these newly identified structures deviate from prior observations of luminous matter, suggesting they are predominantly composed of dark matter. “Gravitational lensing is one of the few and most effective techniques for detecting these structures across vast regions,” Williams stated.

This research is significant, considering that dark matter constitutes about 85% of the universe’s total matter, crucial for the formation and evolution of galaxies and clusters. Understanding its distribution could shed light on its behavior and composition, according to Williams.

“This achievement is not just observational but also paves the way for various analyses, including constraints on cosmological parameters, the relationship between galaxies and their dark matter halos, and their growth and evolution over time,” McCreary highlighted. These parameters include the strength of dark energy, the enigmatic force driving the universe’s accelerating expansion.

While initial findings from the JWST map align with the Lambda CDM model of the universe, McCreary emphasizes that a thorough analysis of the data is still required to unearth new insights. “At first glance, it appears consistent with Lambda CDM, but I remain cautious. A final assessment will depend on complete results.”

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Source: www.newscientist.com

Discover the Top 21 Innovative Ideas of the 21st Century: How We Selected Them and Why They Matter

Posted on January 26, 2026 by Igor Mitreski

What distinguishes a groundbreaking idea from a mediocre one? This is often a challenging distinction to make. Take the example of vaccination: collecting pus from a cowpox-infected individual and injecting it into an eight-year-old boy may seem utterly reckless. Yet, 18th-century physician Edward Jenner’s daring action ultimately led to the eradication of smallpox, a disease that plagued humanity.

With the benefit of hindsight, we recognize that Jenner’s innovation was monumental. This principle of vaccination continues to save millions of lives today. As we progress through the 21st century, we feel it’s essential to reflect on and celebrate transformative ideas from the past 25 years that are reshaping our perspectives, actions, and understanding of the world around us.

Compiling our list of the 21 most impactful ideas of the 21st century involved rigorous discussions among our editorial team. One of our initial challenges was determining if the first quarter of this century would conclude at the beginning or end of 2025. For clarity, we opted for the latter. We navigated debates on various ideas, dedicating particular attention to concepts like the microbiome—establishing it as a legitimate 21st-century notion—and scrutinizing the role of social media, which after much discussion, we deemed largely negative. Ultimately, we recognize that the quality of ideas is subjective.

We developed a robust set of criteria for our selection. To qualify for this list, a concept must already demonstrate a significant impact on our self-understanding, health, or broader universe. Additionally, it should be grounded in scientific discovery, with a strong idea underpinning it. Lastly, the development must have occurred within the last 25 years.

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Rather than trying to predict the future, it’s important to take the time to reflect on the past.
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While the last criterion may appear straightforward, we encountered numerous proposals that remain unrealized. The discovery of gravitational waves in the 21st century opened new cosmic vistas, but their prediction dates back a century to Albert Einstein. Similarly, ideas like weight loss medications, personalized medicine, and mRNA vaccines show promise, but their full potential has yet to be achieved—perhaps these will make the list in 2050.

During our selection process, we couldn’t disregard ideas that initially seemed appealing but faltered. Therefore, we also crafted a list of the five most disappointing ideas of the century thus far. The line between success and failure can sometimes blur, leading to controversial choices in our best ideas list. For instance, while many would advocate for the removal of smartphones, we ultimately view them as largely beneficial. Likewise, the ambitious global warming target of 1.5°C can be seen as a failure, especially as new reports indicate that average global temperatures have surpassed this benchmark for the first time. Nonetheless, we argue that striving to reduce the threshold from 2°C remains one of the century’s monumental ideas, setting a standard for global climate ambition.

Advancing away from fossil fuels is undoubtedly crucial, and prominently featured in this effort is Elon Musk. In 2016, before Musk ventured into social media and politics, his company Tesla launched its first Gigafactory in Nevada, marking a pivotal moment in the transition to renewable energy by utilizing economies of scale to transform transportation and energy systems. Conversely, other approaches to fighting climate change, such as alternative fuels and carbon offsets, appear more harmful than beneficial.

One significant takeaway from our selection process is that revolutionary ideas often arise by chance. For many, a working outlet can be the catalyst for a few minutes of smartphone scrolling during a lengthy commute. However, for two physicists in 2005, their discovery altered the global decarbonization strategy. This breakthrough also unveiled the foundations of our complex thought processes, illustrating that brain regions don’t operate in isolation but are interwoven into a robust network. This understanding has revolutionized our approach to diagnosing and treating neurological issues.

Looking back over the past quarter-century, it’s evident that the world has transformed considerably. We successfully dodged the Millennium Bug, the human genome’s first draft was completed, and the International Space Station welcomed its first crew. Concepts like “Denisovans” and “microbiomes” were unknown to us. In our pages, we celebrated innovations like wireless communication and marveled at miniaturized computer chips driving these technologies. “At its core is a device known as a Bluetooth chip,” we stated, positing it as the next big thing—a prediction that, in hindsight, was flawed, since truly transformative technologies extend beyond mere convenience.

This experience highlights the folly of predictions, as they can often be overlooked in the rush for the next trending innovation. Thus, rather than striving to foresee the future, we ought to invest time in contemplating the past. The advancements we’ve witnessed in health, technology, and environmental conservation suggest that this century has made the world a better place. Let’s hope, without necessarily predicting, that this momentum continues into the future.

Source: www.newscientist.com

Supermassive Dark Matter Stars Could Be Hidden in the Early Universe

Posted on November 28, 2025 by

Exotic stars may be fueled by dark matter

remote vfx/getty images

We might be observing the earliest indications of peculiar stars that harness dark matter. These dark stars could provide explanations for some of the universe’s most enigmatic entities, and offer insights into the actual nature of dark matter itself.

Standard stars are birthed when a gas cloud collapses, leading to a core dense enough to initiate nuclear fusion. This fusion generates significant heat and energy, radiating into the surrounding gas and plasma.

Dark stars could have emerged in a similar fashion during the universe’s infancy, a period of higher density which also saw a notably concentrated presence of dark matter. If a gas cloud collapsing into a star contains substantial dark matter, it may begin to collide and dissipate prior to nuclear fusion, generating enough energy to illuminate the dark star and halt further collapse.

The process leading to the formation of dark stars is relatively straightforward, and currently, a team led by Katherine Freese from the University of Texas at Austin is exploring its potential outcome.

In an ordinary large star, once the hydrogen and helium are depleted, it continues fusing heavier elements until it runs out of energy and collapses into a black hole. The more mass the star contains, the quicker this transition occurs.

However, the same is not true for dark stars. “By incorporating dark matter into a star roughly the mass of the Sun, and sustaining it through dark matter decay rather than nuclear means, you can continuously nourish the star. Provided it receives enough dark matter, it won’t undergo the nuclear transformations that lead to complications,” explains George Fuller, a collaborator with Freese at the University of California, San Diego.

Despite this, general relativity imposes a limit on how long dark matter can preserve these unusual giants. Albert Einstein’s theory suggests that an object’s gravitational field does not increase linearly with mass; instead, gravity intensifies the gravitational force. Ultimately, an object may reach a mass at which it becomes unstable, with minor variations overpowering its gravitational pull and resulting in a collapse into a black hole. Researchers estimate this threshold for a dark star is between 1,000 and 10 million times the Sun’s mass.

This mass range makes supermassive dark stars prime candidates for addressing one of the early universe’s profound mysteries: the existence of supermassive black holes. These giants were spotted relatively early in the universe’s history, but their rapid formation remains a puzzle. One prevailing theory posits that they didn’t arise from typical stars, but rather from some colossal “seed.”

“If a black hole weighs 100 solar masses, how could it possibly grow to a billion solar masses in just a few hundred million years? This is implausible if black holes were formed solely from standard stars,” asserts Freese. “Conversely, this situation changes significantly if the origin is a relatively large seed.” Such faint stars could serve as those seeds.

Yet, the enigmas of the early universe extend beyond supermassive black holes that dark stars could elucidate. The James Webb Space Telescope (JWST) has unveiled two other unforeseen object types, referred to as the little red dot and the blue monster, both appearing at substantial distances. The immediate hypothesis for these is that they are compact galaxies.

However, like supermassive black holes, these objects exist too far away and too early in universal history for simple formation explanations. Based on observations, Freese and her associates propose that both the little red dot and the blue monster may represent individual, immensely massive dark stars.

If they indeed are dark stars, they would display particular clues in their light. This aspect pertains to specific wavelengths that dark stars should ostensibly absorb. Normal stars and galaxies dense with them are too hot to capture that light.

Freese and colleagues have found possible indicators of this absorption in initial JWST observations of several distant entities; however, the data is too inconclusive to confirm its existence. “Currently, of all our candidates, two could potentially fit the spectrum: a solitary supermassive dark star or an entire galaxy of regular stars,” Freese notes. “Examining this dip in the spectrum, we’re convinced it points to a dark star rather than a conventional star-filled galaxy. But for now, we only possess a faint hint.”

While it remains uncertain if we have definitively detected a dark star, this development marks progress. “It isn’t a definitive finding, but it certainly fuels motivation for ongoing inquiries, and some aspects of what JWST has been examining seem to align with that direction,” remarks Dan Hooper from the University of Wisconsin-Madison.

Establishing whether these entities are genuinely dark stars necessitates numerous more observations, ideally with enhanced sensitivity; however, it remains ambiguous whether JWST can achieve the level of detail required for such distant galaxies or dark stars.

“Confirming the existence of dark stars would be a remarkable breakthrough,” emphasizes Volodymyr Takistov from the High Energy Accelerator Research Organization in Japan. This could facilitate new observational avenues into foundational physics. This is particularly true if dark stars are recognized as seeds for supermassive black holes. Freese, Fuller, and their team deduced that the mass at which a black hole collapses correlates with the mass of the dark matter particle annihilating at its center, implying that supermassive black holes could serve as metrics to evaluate or at least restrict dark matter properties. Of course, validating the existence of dark stars is the first priority. “Even if these entities exist, their occurrence is rare,” Hooper states. “They are uncommon, yet significant.”

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Why Dark Matter Is Still One of Science’s Greatest Mysteries

Posted on November 27, 2025 by

“As we approach the late 2020s, it is an incredibly exciting era for dark matter research…”

Sackmestelke/Science Photo Library

This is an extraordinary moment for dark matter researchers. Despite cuts in funding from governments globally, dark matter continues to represent one of the most captivating and significant unsolved mysteries in physics and in the broader scientific landscape. The majority of matter in the universe seems invisible. For every kilogram of visible matter, there are approximately five kilograms of dark matter. This is inferred from the gravitational influence dark matter exerts on the structures of visible components in the universe.

Galaxy clusters are most effectively explained when considering dark matter as a component. Observations of the distribution of the earliest light in the universe fit theoretical predictions only by including dark matter in the model. Many other observations similarly support this view. Dark matter is abundant and remains undetectable unless we study its effects on normal matter.

As we enter the late 2020s, it’s a thrilling period for dark matter research. Investigations by the European Space Agency’s Euclid Space Telescope promise to deepen our understanding of galactic structures. Simultaneously, the Vera C. Rubin Observatory has commenced a decade-long sky survey that is likely to transform our comprehension of satellite galaxies orbiting larger galaxies. These dynamics enhance our understanding of how dark matter influences visible matter.

Exploring phenomena we know exist yet cannot observe directly challenges our creativity as scientists. Some of the pivotal questions that we must ponder include: Can we trap dark matter particles in a laboratory setting? If not, what methods can we employ to analyze their properties?

The solution lies in progressing from established knowledge. We suspect that dark matter behaves similarly to known matter, indicating we might utilize the same mathematical frameworks, like quantum field theory (QFT), to investigate it.

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We are increasingly focusing on finding evidence of dark matter scatterings, not just impacts on targets.
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Quantum field theory can seem complex, and indeed it is. However, a deep understanding is not mandatory to grasp its essence. It is potentially the most fundamental physical theory, harmonizing special relativity with quantum mechanics (excluding general relativity). It suggests that interactions at any point in the universe might give rise to particles due to respective fields.

Imagine a strawberry field. Strawberries grow in specific places due to certain characteristics of those space-time coordinates. These areas possess conditions suitable for strawberry flowers to flourish. The potential for strawberries exists throughout the field, yet only select areas yield blossoms. Similarly, QFT posits the existence of particles.

QFT is intricate, a realm where even experts invest years to cultivate understanding. Even when considering the application of QFT to dark matter to glean useful insights, a critical question arises: How can one formulate an equation for something with minimal known properties?

Sociologically, it’s fascinating to observe the varied responses from scientists. Over the past decade, a popular method for addressing what remains unknown has involved crafting “effective field theory” (EFT). EFT enables the formulation of generalized equations that can be adapted based on empirical observations.

EFT can also be designed with specific experimental frameworks in mind. A key strategy for unraveling dark matter mysteries involves conducting direct detection experiments. Through these efforts, we aspire to witness interactions between dark and visible matter that yield observable results in ground-based studies. Over the years, methods of direct detection have matured and diversified. Researchers are not only looking for signs of dark matter striking targets; they are increasingly seeking footprints of dark matter scattering from electrons. This shift requires an evolution of EFT to accommodate new experimental insights.

In a recent preprint, researchers Pierce Giffin, Benjamin Lillard, Pankaj Munbodh, and Tien-Tien Yu present an EFT aimed at better addressing these scattering interactions. This paper, which has not yet undergone peer review, captured my attention as a prime example of research that may not make headlines but represents essential progress. Science demands patience, and I trust our leaders will remain cognizant of that.

Chanda Prescod-Weinstein is an associate professor of physics and astronomy at the University of New Hampshire. She is the author of Turbulent Universe and upcoming books The Ends of Space and Time: Particles, Poetry, and the Boogie of Cosmic Dreams.

What I Am Reading
I just completed the captivating debut novel by Addie E. Sitchens: Dominion.

What I See
I recently caught up on the summer episodes of Emmerdale, and they were quite surprising!

What I Am Working On
My collaborators and I are exploring intriguing new research ideas related to dark matter scenarios.

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Source: www.newscientist.com

Lava Tubes Hold Secrets of Unidentified ‘Microbial Dark Matter’ – Sciworthy

Posted on November 27, 2025 by

Mars’ surface is not currently conducive to human life. It presents extreme challenges, including a tenuous atmosphere, freezing temperatures, and heightened radiation levels. While Earth’s extremophiles can tackle some obstacles, they can’t handle them all simultaneously. If Martian life exists, how do these microbes manage to survive in such an environment?

The answer might lie within caves. Many researchers believe that ancient lava tubes on Mars formed billions of years ago when the planet was warmer and had liquid water. Caves serve as shelters against radiation and severe temperatures found on the Martian surface. They also host the nutrients and minerals necessary for sustaining life. Although scientists cannot yet explore Martian caves directly, they are examining analogous sites on Earth to establish parameters for searching for life on Mars.

A research team, led by C.B. Fishman from Georgetown University, investigated the microorganisms inhabiting the lava tubes of Mauna Loa, Hawaii, to learn about their survival mechanisms. Thanks to careful conservation efforts by Native Hawaiians, these lava tubes remain undisturbed by human activity. Researchers believe that both the rock structures in Mauna Loa Cave and the minerals formed from sulfur-rich gases bear similarities to Martian cave formations.

The team analyzed five samples from well-lit areas near the cave entrance, two from dimly lit zones with natural openings known as skylights, and five from the cave’s darkest recesses. Samples were chosen based on rock characteristics, including secondary minerals like calcite and gypsum, and primary iron-bearing minerals such as olivine and hematite.

Findings revealed significant variation in mineralogy within the cave, even over small distances. The bright samples were predominantly gypsum, while the dark samples lacked these key minerals. Instead, one dark sample was rich in iron-bearing minerals, while another contained mainly calcite, gypsum, and thenardite.

To identify the microorganisms within the samples, the team employed the 16S rRNA gene to recognize known microbes and understand their relationships. They also reconstructed complete genomes from cave samples using a method called metagenomic analysis. This technique is akin to following instructions to assemble various models from mixed DNA fragments. Such insights help researchers grasp how both known and unknown microorganisms thrive in their respective environments.

The team discovered that approximately 15% of the microbial genomes were unique to specific locations, with about 57% appearing in less than a quarter of the samples. Furthermore, microbial communities in dark regions exhibited less diversity and were more specialized compared to those in well-lit areas. While dark sites were not as varied as bright ones, each supported its own distinct microbial community.

To explain this difference, the researchers proposed that dark microbes have limited survival strategies since photosynthesis is impossible without light. Instead, these microbes extract chemical energy from rocks and decaying organic matter, much like how humans derive energy from breaking down food.

The findings from metagenomic data indicated that even though sulfur minerals were abundant, very few microorganisms specialized in sulfur consumption were present. This aligns with expectations in oxygen-rich environments, as oxygen tends to react with sulfur, making it unavailable to microorganisms. The researchers suggested that sulfur-metabolizing microbes may be more commonly found in low-oxygen environments, such as Mars.

Additionally, the study revealed that a majority of the microorganisms found in these caves were previously undescribed by science, contributing to what is referred to as microbial dark matter. The existence of such unknown microorganisms hints at novel survival strategies.

The research team concluded that lava tube caves could be a crucial source of new microorganisms, aiding astrobiologists in their quest to understand potential life forms on Mars. They recommended that future investigations into Martian caves should focus on detecting small-scale microbes in various mineral contexts. Over time, the interplay between cave conditions and Martian microorganisms may be unveiled as Mars becomes less habitable.

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Source: sciworthy.com

Potential First Signs of Dark Matter Discovered

Posted on November 26, 2025 by

Unexplained radiation surrounding the Milky Way may hint at dark matter’s composition

Trif/Shutterstock

SEI 275649097 — Unexplained radiation surrounding the Milky Way may hint at dark matter’s composition

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A mysterious glow detected in the outer regions of the Milky Way may provide the first clues about the nature of dark matter, yet astronomers caution that it’s premature to draw any definitive conclusions.

Dark matter is theorized to account for 85% of the universe’s total mass, but scientists have struggled to identify the particles constituting it.

Among the potential candidates for dark matter are weakly interacting massive particles (WIMPs). These elusive particles are notoriously hard to detect as they seldom interact with normal matter but are believed to occasionally self-annihilate, creating bursts of high-energy radiation in the form of gamma rays.

If dark matter is uniformly distributed across the galaxy as indicated by its gravitational effects, and if it consists of WIMPs, we should observe gamma rays as these particles self-annihilate. For over a decade, astronomers have been investigating whether the anomalously high gamma-ray emissions from the galactic center could signal this phenomenon, yet conclusive evidence remains elusive.

Now, Tomonori Toya, a professor at the University of Tokyo, claims he may have detected such a signal emanating from the Milky Way’s outer halo, utilizing 15 years’ worth of observations from NASA’s Fermi Gamma-ray Space Telescope.

Toya devised a model predicting the expected gamma-ray radiation in this region based on established sources like stars, cosmic rays, and vast bubbles of radiation identified above and below the Milky Way. Upon subtracting this known radiation from the total observed by Fermi, he found a residual gamma-ray glow with an energy level around 20 gigaelectronvolts.

This specific gamma-ray energy strongly aligns with the theoretically anticipated emissions from WIMPs’ self-annihilation, according to Toya. Although he admits it is too early to assert that these gamma-ray spikes are definitively due to dark matter, he describes the findings as “the most promising candidate for radiation from dark matter known to date.”

“Though the research began with the aim of identifying dark matter signals, I initially felt skeptical—like winning the lottery. When I first observed what seemed to be a signal, I approached it with caution,” says Totoni. “However, after thoroughly checking everything and confirming its accuracy, I was filled with excitement.”

“This represents a significant result worthy of further investigation, but firm conclusions cannot be drawn at this stage,” states Francesca Karoly from the French National Center for Scientific Research in Annecy. Accurately modeling all gamma-ray sources in the Milky Way, aside from dark matter, is quite complex, and Totoni has yet to deeply validate her models.

Silvia Manconi of France’s Sorbonne University asserts that the results need additional scrutiny, and more robust models are essential to establish whether the signals are genuine. Additionally, gamma-ray signals from other sources, like dwarf galaxies, are still unobserved and require thorough explanation, she mentions.

Many alternative radiation sources, including radio waves and neutrinos, will also need analysis to ensure the gamma rays aren’t being attributed to something else, says Anthony Brown from Durham University, UK. “Analyzing from just one perspective isn’t sufficient,” he states. “Dark matter necessitates an abundance of high-quality data.”

CERN and Mont Blanc: Exploring dark matter and frozen phenomena in Switzerland and France

Get ready to experience the wonders of CERN, the European center for particle physics, situated near the picturesque city of Geneva, where scientists operate the renowned Large Hadron Collider.

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Source: www.newscientist.com

Mysterious Glow Around the Milky Way May Provide First Evidence of Dark Matter

Posted on November 26, 2025 by

For nearly a century, dark matter has posed a significant enigma. Although it outnumbers ordinary matter by a ratio of five to one, it remains invisible and undetectable by current technology.

A daring new analysis of 15 years of data from NASA’s Fermi Gamma-ray Space Telescope now claims to shed light on this mystery.

The latest research reveals the detection of a peculiar halo-like glow of gamma rays surrounding the Milky Way galaxy, with distinct peaks in energy that align closely with the signals predicted for a specific type of hypothetical dark matter particle.

These particles, referred to as weakly interacting massive particles (WIMPs), can generate gamma rays by annihilating one another.

“If this is validated, it would be the first instance where humanity has ‘seen’ dark matter,” stated Professor Tomonori Toya, an astronomer at the University of Tokyo and co-author of the study.

In an interview with BBC Science Focus, he expressed his initial skepticism: “When I first noticed what looked like a traffic light, I was doubtful, but after careful investigation, I became convinced it was accurate—it was an exhilarating moment,” he shared.

However, despite the excitement surrounding the new signals, independent experts caution that this discovery is far from conclusive.

This possible breakthrough emerges nearly a century after Swiss astronomer Fritz Zwicky first proposed dark matter’s existence, after observing that the galaxies in the Milky Way cluster were moving too swiftly for their visible mass.

Mr. Toya’s study, published in the Journal of Cosmology and Astroparticle Physics, scrutinized 15 years of data from the Fermi telescope, focusing on the regions above and below the Milky Way’s main disk—known as the galactic halo.

After modeling and accounting for known sources of gamma rays, such as interstellar gas interactions, cosmic rays, and massive bubbles of high-energy plasma at the galaxy’s center, he identified a leftover component that shouldn’t exist.

“We detected gamma rays with a photon energy measuring 20 giga-electron volts (or an impressive 20 billion electron volts), extending in a halo-like formation toward the Milky Way’s center,” Toya explained. “This gamma-ray-emitting component aligns with the expected shape of a dark matter halo.”

A gigaelectronvolt (GeV) represents a unit of energy utilized by physicists to quantify subatomic particles’ energy levels—approximately a billion times the energy that a single electron attains when traversing a 1-volt battery.

The potential dark matter signal identified by Toya sharply rises from a few GeV, peaks around 20 GeV, and subsequently declines, consistent with predictions for WIMPs, which possess about 500 times the mass of a proton.

This gamma-ray intensity map illustrates a signal that may originate from dark matter encircling the Milky Way halo. The gray horizontal bar in the central area represents the galactic plane, which was exempted from the analysis to avoid strong astrophysical radiation. – Photo credit: Tomonori Toya, University of Tokyo

In Totani’s perspective, this data significantly indicates the existence of dark matter. “This marks a crucial advancement in astronomy and physics,” he asserts.

Nevertheless, Jan Conrad, a professor of astroparticle physics at Stockholm University in Sweden and an independent expert in gamma-ray searches for dark matter, advises prudence.

“Making claims based on Fermi data is notoriously challenging,” he remarked to BBC Science Focus.

This isn’t the first instance of astronomers witnessing such phenomena; the story stretches back to 2009, shortly after the Fermi telescope’s launch. In that year, researchers identified an unexplained surplus of gamma rays emanating from the galactic center.

For years, this finding stood out as a compelling hint of dark matter. However, Conrad pointed out that even after 16 years, the scientific community has yet to arrive at a consensus about the signal’s dark matter roots.

“It’s believed to be related to dark matter,” he claims. “Despite accumulating data and enhanced methods since then, the question of dark matter’s existence remains unresolved.”

Even at this juncture, researchers who have spent over a decade working to disprove the galactic center excess are unable to definitively prove it is astrophysical in nature (originating from sources other than dark matter), nor can they confirm it is attributable to dark matter. The issue remains unsolved.

Conrad emphasized that the emerging signals from the halo are insufficiently studied and will likely necessitate many more years of investigation for verification. Both the new halo anomaly and the much-debated galactic center signal share a common challenge: noise interference.

In these regions, gamma rays potentially stemming from dark matter annihilation may also originate from numerous other, poorly understood sources—complicating efforts to reach definitive conclusions.

“The uncertainties surrounding astrophysical sources make it exceedingly difficult to assert strong claims,” Conrad stated.

Despite their differing confidence levels, both Totani and Conrad highlight the same forthcoming focus: dwarf galaxies.

These small, faint galaxies orbiting the Milky Way are believed to contain significant amounts of dark matter while exhibiting minimal astrophysical gamma-ray background, rendering them ideal for studying dark matter annihilation.

“If we detect a similar excess in dwarf galaxies, that would provide compelling evidence,” Conrad said. “Dwarf galaxies provide a much cleaner environment, allowing for potential confirmation.”

Dr. Toya concurred, noting, “If the results of this study are validated, it wouldn’t be surprising to observe gamma rays emitting from dwarf galaxies.”

The Cherenkov Telescope Array Observatory (CTAO) is the most sensitive ground-based gamma-ray observatory ever constructed, offering a powerful new approach to scrutinize whether this enigmatic signal is indeed dark matter. – Photo credit: Getty

Yet, the ultimate verification of Toya’s discovery might be closer to home. Experiments designed to detect dark matter are currently taking place in facilities situated deep underground around the world.

“If we were to observe a signal there that aligns with a WIMP of the same mass…that would present a robust argument, as it would be much cleaner,” Conrad pointed out.

In the coming years, the next-generation Cherenkov Telescope Array Observatory (CTAO) will significantly enhance sensitivity to high-energy gamma rays, enabling researchers to analyze halo signals with greater detail.

“Naturally, if this turns out to be true, it’s a significant discovery,” Conrad said. “The true nature of dark matter remains elusive. A clear signal indicating dark matter particles would be monumental. However, further research is essential to explore alternative explanations for this excess.”

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Source: www.sciencefocus.com

Scientists Have Studied Dark Matter for Decades—One May Have Caught a Glimpse.

Posted on November 26, 2025 by

Few entities in the universe are as intricate as dark matter, an unseen and exotic “matter” believed to account for most of the mass within galaxies.

The hypothesis suggests that aligning our current physical theories with observed universe phenomena necessitates the presence of substantial volumes of invisible matter. Scientists are convinced that this “missing mass” is real due to its gravitational pull, although direct detection has eluded them; they can only infer its presence.

Nearly a century after dark matter was first hypothesized, Japanese astrophysicists claim to have found the first concrete evidence of its existence—gamma rays emanating in a halo-like formation near the heart of the Milky Way.

“Naturally, we’re extremely enthusiastic!” said Tomonori Toya, a professor in the astronomy department at the University of Tokyo, in an email to NBC News. “While the research aimed at detecting dark matter, I thought the chances of success felt akin to hitting the jackpot.”

Toya’s assertion of being the first to identify dark matter is met with skepticism by some experts. Nonetheless, the findings, published on Tuesday in the Journal of Cosmology and Astroparticle Physics, shed light on the relentless pursuit of dark matter and the challenges of investigating the unseen in space.

Dark matter is estimated to constitute around 27% of the universe, whereas ordinary matter (like humans, objects, stars, and planets) makes up roughly 5%, according to NASA. The remainder consists of another enigmatic component known as dark energy.

Toya’s research utilized data from NASA’s Fermi Gamma-ray Space Telescope, which is focused on the center of our galaxy. This telescope is adept at capturing a powerful form of electromagnetic radiation called gamma rays.

The idea of dark matter was first proposed by Swiss astronomer Fritz Zwicky in the 1930s when he detected anomalies in the mass and movement of galaxies within the gigantic Coma cluster. The galaxies’ velocities exceeded expectations, implying they were bound together rather than escaping the cluster.

The subsequent theory introduced a truly extraordinary form of matter. Dark matter is undetectable because it does not emit, absorb, or reflect light. However, given its theoretical mass and spatial occupation in the universe, its presence can be inferred from its gravitational effects.

Various models strive to elucidate dark matter, but scientists contend that it comprises exotic particles that exhibit different behaviors compared to familiar matter.

One widely considered theory posits that dark matter consists of hypothetical particles known as WIMPs (weakly interacting massive particles), which have minimal interaction with ordinary matter. However, when two WIMPs collide, they can annihilate and emit potent gamma rays.

In his investigation, Toya identified a gamma-ray emission equating to about one millionth of the brightness of the Milky Way. The gamma rays also appeared spread out in a halo-like formation across extensive sky areas. Should these emissions originate from a single source, it may indicate that black holes, stars, or other cosmic entities, rather than diffuse dark matter, generate the gamma rays.

Gamma-ray intensity map covering roughly 100 degrees toward the galactic center. The gray horizontal line in the central section corresponds to the galactic plane, which was excluded from the analysis to avoid strong astrophysical radiation.Tomonori Toya / University of Tokyo

“To my knowledge, there’s no cosmic phenomena that would cause radiation exhibiting the spherical symmetry and unique energy spectrum observed here,” Toya remarked.

However, certain scientists not associated with the study expressed doubts about the findings.

David Kaplan, a physics and astronomy professor at Johns Hopkins University, emphasized that our understanding of gamma rays is still incomplete, complicating efforts to reliably connect their emissions to dark matter particles.

“We don’t yet know all the forms of matter in the universe capable of generating gamma rays,” Kaplan indicated, adding that these high-energy emissions could also originate from rapidly spinning neutron stars or black holes that consume regular matter and emit energetic jets.

Thus, even when unusual gamma-ray emissions are identified, deriving meaningful interpretations is challenging, noted Eric Charles, a scientist at Stanford University’s SLAC National Accelerator Laboratory.

“There are numerous intricacies we don’t fully grasp, and we observe a plethora of gamma rays across extensive areas of the sky linked with galaxies. It’s particularly difficult to decipher what transpired there,” he explained.

Dillon Braut, an assistant professor at Boston University’s Department of Astronomy and Physics, remarked that the gamma-ray signals and halo-like formations discussed in the study appear in regions of the sky that are “incredibly challenging to model.”

“Therefore, any claims should be treated with utmost caution,” Braut communicated to NBC News via email. “And, naturally, extraordinary claims necessitate extraordinary proof.”

Kaplan labeled the study as “intriguing” and “meriting further investigation,” but remained uncertain if subsequent analyses would substantiate the findings. Nonetheless, he anticipates that future advancements will allow scientists to directly validate dark matter’s existence.

“It would be a monumental shift as it appears poised to dominantly influence the universe,” he stated. “It accounts for the evolution of galaxies and, consequently, stars, planets, us, and is crucial for comprehending the universe’s origin.”

Toya himself acknowledged that further exploration is necessary to authenticate or refute his assertions.

“If accurate, the outcomes would have such significance that the research community would earnestly evaluate their legitimacy,” he noted. “While I have confidence in my findings, I hope other independent scholars can verify these results.”

Source: www.nbcnews.com

Study Reveals Disappearance of Dark Matter as Cause for Excess Galactic Centers in the Milky Way

Posted on October 21, 2025 by

The galactic center excess refers to an unexpected intensity of gamma rays emerging from the core of the Milky Way galaxy.

This view displays the entire sky at energies exceeding 1 GeV, derived from five years of data from the LAT instrument on NASA’s Fermi Gamma-ray Space Telescope. The most striking aspect is a luminous band of diffuse light along the center of the map, indicating the central plane of the Milky Way galaxy. Image credit: NASA/DOE/Fermi LAT collaboration.

Gamma rays are a form of electromagnetic radiation characterized by the shortest wavelengths and the highest energy.

The intriguing gamma-ray signal from the Milky Way’s center was initially observed in 2009 by the Large Area Telescope, the primary instrument of NASA’s Fermi Gamma-ray Space Telescope.

The source of this signal remains under discussion, with main hypotheses involving self-annihilating dark matter and undetected populations of millisecond pulsars.

“When Fermi directed its gaze toward the galaxy’s center, the outcome was unexpected,” remarked Dr. Noam Libeskind, an astrophysicist at the Leibniz Institute for Astrophysics in Potsdam.

“The telescope detected an excessive number of gamma rays, the most energetic form of light in the universe.”

“Astronomers worldwide were baffled, and numerous competing theories emerged to clarify the so-called gamma-ray excess.”

“After extensive discussion, two primary theories surfaced: either these gamma rays stem from millisecond pulsars (highly dense neutron stars rotating thousands of times per second) or from dark matter particles colliding and annihilating. Both theories, however, have their limitations.”

“Nonetheless, our findings strongly support the notion that the gamma-ray excess arises from dark matter annihilation.”

In their study, Dr. Libeskind and his team simulated the formation of the Milky Way galaxy under conditions akin to those in Earth’s neighboring universe.

They discovered that dark matter does not radiate outward from the galaxy’s core but is organized similarly to stars, suggesting that it could also contribute to the excess gamma rays.

“The Milky Way has long been recognized as existing within a spherical region filled with dark matter, often referred to as a dark matter halo,” explained Dr. Mourits Mikkel Mur, an astrophysicist at the Potsdam Leibniz Institute for Astrophysics and the University of Tartu.

“However, the degree to which this halo is aspheric or ellipsoidal remains unclear.”

“We analyzed simulations of the Milky Way and its dark matter halo and found that the flattening of this region sufficiently accounts for the gamma-ray excess due to self-annihilation of dark matter particles.”

“These calculations indicate that the search for dark matter particles capable of self-annihilation should be emphasized, bringing us closer to uncovering the enigmatic properties of these particles.”

A study of the survey results was published in this month’s edition of Physical Review Letters.

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Mikel Mur the Moor et al. 2025. Excess forms of dark matter in Fermi LAT galactic center Milky Way simulations. Physics. Pastore Rhett 135, 161005; doi: 10.1103/g9qz-h8wd

Source: www.sci.news

Everyday Sugar Could Help Uncover Dark Matter

Posted on October 17, 2025 by

A thin crystalline film of table sugar, or sucrose, captured using a polarized light microscope.

Carl Gough/Science Photo Library

SEI 270572247 — A thin crystalline film of table sugar, or sucrose, captured using a polarized light microscope.

Carl Gough/Science Photo Library

Researchers have developed a novel method to probe dark matter utilizing expansive crystals of sucrose, or table sugar, yet their findings thus far yield nothing more than a bittersweet outcome.

Dark matter is believed to exist due to its elusive gravitational pull on galaxies; however, despite decades of exploration for potential dark matter particles, little evidence has surfaced. Historically, many searches focused on weakly interacting massive particles (WIMPs), considered leading candidates for dark matter. Yet, even the most meticulous searches have proven fruitless.

Conventional WIMP detectors aim to identify light flashes produced by interactions between dark matter particles and regular matter, assuming that these particles are relatively sizable, around 2 to 10,000 times the mass of a proton. Although this explanation is the most straightforward, the possibility exists that WIMPs are lighter, albeit creating challenges with the theory.

Recently, Federica Petricca and her team at the Max Planck Institute for Physics in Munich, Germany, have sought these lighter WIMPs utilizing a detector constructed from sugar crystals chilled to extremely low temperatures.

Very light WIMPs are expected to predominantly interact with extremely light atoms like hydrogen; however, utilizing pure hydrogen as a detector is challenging due to its low density, which diminishes interaction probabilities. On the other hand, sucrose comprises 22 hydrogen atoms in each molecule, leading to a significantly higher density than pure hydrogen.

Petricca and her colleagues initially cultivated sucrose crystals from a concentrated sugar solution over the span of a week before reducing the temperature of the crystals to 7 thousandths of a degree above absolute zero. They monitored potential dark matter interactions by employing highly sensitive thermometers to detect minimal heat increases and photon sensors to register flashes of light.

Following 19 hours of experimentation, the sugar crystals did emit light at levels comparable to interactions with larger particles; however, they did not capture the weaker signals that might indicate the presence of WIMPs.

Scientists assert that sugar crystals offer surprising sensitivity for detecting potential dark matter interactions. Carlos Blanco of Penn State notes that researchers may be able to identify subtle recoils from lightweight WIMPs. However, it remains uncertain if this experiment can effectively exclude other potential sources of crystal formation, like radioactive carbon-14, commonly present in various sugars.

CERN and Mont Blanc: Dark Matter and Frozen Matter in Switzerland and France

Get ready to be inspired by CERN, the heart of particle physics in Europe, situated near the lovely Swiss city of Geneva, where researchers manage the well-known Large Hadron Collider.

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Source: www.newscientist.com

The Heart of Our Galaxy Could Be Teeming with Dark Matter Particles

Posted on October 17, 2025 by

Gamma rays are detected in unusually high amounts at the center of the Milky Way galaxy

The center of our galaxy is exhibiting unusual behavior, potentially linked to dark matter. In 2009, observations from the Fermi Gamma-ray Space Telescope uncovered unexpectedly high levels of gamma ray emissions from the Milky Way’s center, a phenomenon termed galactic central gamma-ray excess (GCE). Simulations suggest these gamma rays could arise from the annihilation of dark matter particles.

The discussion surrounding the origins of GCE has intensified since its initial discovery, leading to two main theories. The first posits that it may stem from a previously unobserved population of pulsars, rapidly spinning neutron stars that emit considerable radiation.

Alternatively, it could be linked to weakly interacting massive particles (WIMPs), long considered primary candidates for dark matter. These particles seldom interact with normal matter, but a collision between two can lead to annihilation and consequently, a burst of gamma rays.

However, the dark matter explanation has lost traction recently, especially after searches for WIMPs yielded no results. “The dark matter interpretation demands greater proof due to insufficient direct evidence of its existence despite thorough investigations,” notes Jeff Grube from King’s College London.

Another factor contributing to this skepticism is that dark matter in galaxies is expected to be evenly distributed, while GCEs display a flattened distribution. Yet, new simulations by Joseph Silk and his colleagues at Johns Hopkins University in Maryland indicate that this discrepancy may not be significant.

These new simulations carefully considered the Milky Way’s history in relation to GCEs. “We know from history that our galaxy merged with smaller galaxies billions of years ago, which contributed to the formation of dark matter,” noted Silk. “No one would have anticipated that the galaxy’s center would exhibit spherical symmetry due to this history.”

The results confirmed this notion, resulting in a distorted dark matter distribution aligned with the shape of GCE, reviving the dark matter theory. However, the mystery remains unresolved, as pulsars continue to be a viable explanation. “At best, the situation is still ambiguous,” added Grube.

The current gamma-ray observatories do not possess the capability to distinguish between these two theories; however, the Cherenkov Telescope Array observatories, under construction in the Canary Islands and Chile and expected to begin operations in 2026, could provide clarity.

“In many ways, there’s a 50 percent chance that we may have discovered significant dark matter, but we require new telescopes to confirm this,” stated Silk. If GCE is indeed the result of dark matter, it could offer the best insight yet into this enigmatic substance that underpins the universe.

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Source: www.newscientist.com

Clues to Exotic Dark Matter Particles Could Be Found in LHC Data

Posted on September 24, 2025 by Igor Mitreski

ATLAS Detector of the Large Hadron Collider

Xenotar/Getty Images

SEI 266779422 — ATLAS Detector of the Large Hadron Collider

Xenotar/Getty Images

The theoretical particles known as axions have attracted the attention of physicists for decades, as they are significant candidates for identifying dark matter. Recent research suggests that we might not need new experiments to discover these exotic particles; evidence could already be embedded in existing data from previous particle collider experiments.

Particle colliders like the Large Hadron Collider (LHC), located at CERN near Geneva, Switzerland, discover new particles by colliding protons and ions, analyzing the resulting debris. Now, Gustabo Gilda Silveyra and his team at CERN are exploring another avenue: can we detect when a proton or ion emits a new particle during acceleration? Their findings indicate that this may indeed be possible.

The axion was theorized in the 1970s as part of a pivotal solution to a significant problem in physics. Its importance surpasses even that of antimatter. Although the ongoing search for experimental evidence of axions has not yet yielded results, it raises the possibility that other particles resembling axions might exist. Due to their incredibly low mass, they bear a close resemblance to substantial quantities of light or photons, interacting together with the LHC.

This interaction primarily occurs when protons or ions are accelerated to astonishing energy levels. As these particles approach each other, they begin to emit radiation in the form of photons, which may then collide with one another. Researchers have modeled this scenario, replacing photons with axion-like particles. Their results indicate that accelerated protons exhibit a higher likelihood of generating axion-like particles compared to accelerated ions, with both producing photons simultaneously. Consequently, the team has identified collisions between protons and lead ions as optimal for uncovering signals related to axions influencing photons. The specific proton-lead ion collisions were executed at the LHC in 2016, and the researchers propose that data from these experiments might have been previously overlooked but could contain vital hints about new axion-like particles.

Lucien Haaland Lang from University College London has remarked that this approach presents an intriguing new pathway to uncover potential undiscovered particles, though he cautions about the challenges involved. “Such collision events are rare, and we must be cautious to differentiate our findings from background processes that may inadvertently mimic the signals we seek,” he notes.

Access to older LHC data poses challenges due to updates in software, according to Da Silveira. However, he expresses optimism regarding future experiments at the LHC. “We will be able to adjust the detector to capture this specific signal,” he states.

Identifying a particle signal analogous to an axion does not equate to discovering an actual axion, thus leaving one of the major unresolved questions in physics unanswered. Nonetheless, it expands our understanding of particle physics, prompting inquiries into how new particles might interact with known counterparts and whether they might help explain the enigmatic dark matter that permeates the universe.

Journal Reference: Physical Review Letter, In print

Topics:

Large Hadron Collider/
Particle Physics

Source: www.newscientist.com

Inside the World’s Top Dark Matter Detector: What It’s Really Like to Operate

Posted on September 15, 2025 by Igor Mitreski

Chamkaur Ghag plays a pivotal role in the Lux-Zeplin experiment, a leading dark matter detector

Nova

Deep underground in South Dakota, the most advanced dark matter detector on Earth awaits its moment of discovery. This is the Lux-Zeplin (LZ) experiment, highlighting a vast tank of liquid xenon. Physicist Shankaur Ghag from University College London is among the key leaders in this large scientific collaboration, which aims to unravel about 85% of the universe’s mysteries that still elude us.

Currently, Ghag and his team find themselves at a crucial juncture in the quest for this elusive substance. They are considering plans for a more significant detector called xlzd, which promises to be many times the size of the LZ and even more precise. However, if neither detector can uncover the dark matter, they may need to reassess their understanding of what dark matter is. As Ghag suggests, future dark matter detectors may not be massive underground structures but rather smaller, unassuming devices. He has already devised a prototype of such a detector ahead of his upcoming talks at New Scientist Live this October.

Leah Crane: To start, why is dark matter so essential?

Chamkaur Ghag: On one side, we have all the knowledge that particles and atoms, alongside particle physics, provide about the components of matter. On the contrary, we understand gravity as well. While this may seem comprehensive, a significant issue arises when attempting to merge gravity and particle physics. Our galaxy shouldn’t exist as it does. It remains intact through gravity, which seems to derive from unseen matter. This isn’t just a tiny glue; around 85% of the universe comprises this so-called dark matter.

Why have our efforts to find it been so prolonged, with little success?

At present, we hypothesize that dark matter likely consists of what we term “wimps”—massive, weakly interacting particles that originated in the early universe. Consequently, these rarely interact with other particles, providing only a faint signature, which necessitates a large detector for detection. The larger these detectors are, the greater the chance that dark matter particles will pass through them. Additionally, they must be extremely quiet since even slight vibrations can obscure the signal.

We discuss the theoretical landscape of dark matter, which encompasses the range of masses and characteristics such particles could possess. We’ve already excluded certain regions of this landscape, making it essential to delve even deeper underground with larger detectors to explore where dark matter may still exist.

This painstaking endeavor requires minimizing background noise. For instance, many metals emit small radioactive levels, necessitating rigorous efforts to reduce construction material noise. The LZ detector boasts the lowest background noise and the highest level of radio-purity on the planet.

The LZ is currently the most sensitive detector we have. How does it function?

In essence, it operates as a double-walled thermos, containing several meters of liquid xenon. This xenon resides within a reflective tank, equipped with light sensors positioned above and below. Additionally, an electric field exists within this tank. When a wimp collides with a xenon nucleus, it generates a brief flash of light. However, due to the electric field, it causes the electrons to split apart, producing a second flash from the nucleus.

This two-signal output enables us to ascertain the exact location of an event. The intensity of both the primary and secondary flashes informs us about the microphysics of whether the interaction was caused by a wimp or an unrelated phenomenon, such as gamma rays. To ensure optimal detection, we are positioned miles underground to shield against cosmic rays and also encapsulated in an aquarium to safeguard against the surrounding rock.

This endeavor is undoubtedly complex. What has been the most challenging aspect of making it operational?

In an earlier experiment with a smaller prototype called Lux, I understood what was required to create an instrument tenfold more sensitive. Bringing that theoretical knowledge into practice proved challenging. For me, the toughest challenge lay in ensuring the instrument remained clean and quiet enough to achieve required sensitivity. When deployed with the LZ, it occupies a vast area equivalent to a football pitch, where it must tolerate only a gram of dust spread across its surface.

What is it like working with such an ultra-clean detector underground?

The environment, once a gold mine, retains its industrial atmosphere. You don a hard hat, descend a mile down, and then trek to the lab. Upon entering the lab, you lose sense of the surroundings; it transforms into a clean room filled with computers and equipment—essentially a lab devoid of windows. But the journey underground feels otherworldly.

Outer Detectors of the Lux-Zeplin Experiment

Sanford Underground Research Facility/Matthew Kapust

Historically, wimps have been the primary suspect for dark matter. At what point do we consider the wimp hypothesis invalid if we find no evidence?

Should we construct the XLZDs, the larger detectors intended for this purpose, and reach a point where they fail to detect wimps, it would be hard to sustain the idea of a standard wimp existing if we must venture beyond the capabilities of those instruments. However, until that happens, wimps are still in the game. The void between our current findings and those of the XLZD remains intriguing.

We’ve also developed a much smaller, entirely different detector for dark matter. Can you tell me more about it?

We’ve engineered 150 nanometer wide glass beads coated with lasers. This highly sensitive force detector can determine interactions in three dimensions, allowing us to ascertain which direction an event originated from. This capability is significant as it enables us to filter out terrestrial background influence, such as radioactive decay from geological materials.

This concept seems far removed from large detectors like the LZ. What’s the logic behind its creation? Will we see further advancements in smaller detectors?

Large-scale underground experiments, while large and sensitive, can paradoxically limit sensitivity due to their size. For instance, when a dark matter particle collides with my xenon detector, it may produce 10 photons. A smaller tank can capture all of them, but in a larger tank, these photons could bounce around and only a few are detected.

Furthermore, when a dark matter particle interacts with my detector, it only generates two photons initially. In this scenario, the maximal signal from a detector akin to the LZ diminishes. This has spurred the motivation to search for low-mass dark matter particles beyond the LZ’s detection range, leading us toward alternative detection methods.

If dark matter were to be discovered, what implications would that hold for physics and our understanding of the universe?

The implications would be two-fold: it would conclusively provide answers to what constitutes 85% of the universe, and it would challenge the standard model of particle physics, which currently outlines the known components of reality. Thus, if we discovered dark matter, it may offer the first glimpse beyond this conventional framework. Up until now, we’ve had no solid evidence to deviate from the standard model—this would serve as the first ray of hope.

Topics:

Dark Matter/
Particle Physics

Source: www.newscientist.com

Should It Be “Space-Time” or “Space Time”? And Why Does It Matter?

Posted on September 4, 2025 by Igor Mitreski

“Even trying to explain ‘space’ feels challenging…”

ShutterStock/FastMotion

One of the most challenging aspects of writing a book is the need for authors to seek out blurbs. These endorsements, prominently featured on book covers, can entice readers to make a purchase. Right now, I’m at this stage with The Edge of Spacetime, reaching out for letters of recommendation, asking people to read my work and share positive thoughts in return for something more than just my good intentions.

It’s a bit nerve-wracking, yet it can also be fascinating. Those whose endorsements get published were asked in a specific format—what prompted you to use “space-time” with a hyphen rather than “spacetime”?

This seems like a question of simple grammar, but there’s a deeper issue at play. When discussing space or time individually, we have an intuitive grasp of what we mean. The term “space-time” is somewhat newer to scientific discourse. Historically, many cultures have embraced a unified concept that doesn’t differentiate between space and time as distinct entities.

For me, as a science communicator, explaining this concept is quite challenging. Even articulating “space” is complex. I might say space is where movement occurs, but movement also happens within time. I could define space as the realm where things exist, but a similar statement can be made for time. We even pondered describing space as a geographical location, yet that sounds overly academic and abstract. Essentially, we are referring to a site of spatial dimensions.

To elucidate, there are three dimensions of space and one dimension of time, but time only flows in one direction.

However, as Albert Einstein famously asserted, these aren’t separate phenomena. Observers moving at varying speeds, especially as they approach the speed of light, may disagree on when certain events transpire. They may also hold differing views on the size of objects. To truly understand everything, we must quantify space-time rather than merely space or time. This perspective might not feel intuitive, but it is the most effective way to comprehend the mechanics of the universe.

In this regard, it’s worth considering whether space-time represents a confluence of two familiar phenomena or signifies the emergence of something entirely new. This is where the nuances of grammar reflect our scientific understanding, at least from my viewpoint.

“
It’s worth considering whether space-time is a merger of two familiar phenomena or something new.
“

My last name includes the very first hyphen I encountered. My parents chose to keep both surnames, so to me, Prescod Weinstein signifies both identities.

The hyphenated version of space-time can be interpreted as indicating that what we discuss encompasses both space and time. Conversely, removing the hyphen to form “spacetime” may suggest we are addressing an entirely distinct entity. It embodies attributes of both space and time while existing as a separate third entity.

Are we contemplating something that is both space and time (space-time), or are space and time merely approximations of a fundamentally different conception of space-time? I find myself somewhat ambivalent. In my earlier book, The Blurbriter, I noted this distinction without employing hyphens, thus raising the question of why I chose to make a switch this time around.

The straightforward answer is that the title of the new book appears in the introductory sections of classic cosmology texts. Large-Scale Structure of Space-Time by Stephen Hawking and Father George Ellis states in the very first chapter that solving the equations that describe the universe “in a sense, involves contemplating the edges of space-time.” Just two pages later, they posit that locations where equations deconstruct (like at the heart of a black hole) can be viewed as “representing part of the edge of space-time.”

My book includes chapters that elucidate the types of equations they reference and the role of boundaries and edges in physics. Since I was about to borrow this phrase for my book’s title, I felt compelled to adhere to their terminology.

This is a surface-level explanation. However, at a deeper level, I am unsure where I stand. Like my request for endorsements, I feel inclined to prefer “spacetime” without a hyphen. Yet, I’m also aware of how habitual language can be, given my repeated use of hyphens in the subtitles of my previous work. Scientifically, I lean toward the notion that “space-time” encompasses both space and time, asserting that it is an entirely different fourth dimension: space-time. This may seem like a complex perspective, but I desire to embrace both aspects simultaneously!

Chanda’s Week

What I’m reading

I’m quite excited about the new Charlie Jane Anders novel Lessons from Magic and Disaster.

What I’m seeing

I’ve just caught up with the sci-fi series Invasion, and it’s truly captivating.

What I’m working on

I have a new postdoctoral researcher joining my group.

Chanda Prescod-Weinstein is an associate professor of physics and astronomy at the University of New Hampshire. She is the author of Cosmos with Disabilities and her forthcoming book, Edges of Space-Time: Particles, Poetry, and the Dreams of the Universe.

topic:

Source: www.newscientist.com

Ganymede, Jupiter’s Moon, May Function as a Massive Dark Matter Detector

Posted on August 18, 2025 by Igor Mitreski

View of Ganymede from NASA’s Juno spacecraft

junocam/nasa/jpl-caltech/swri/msss/kalleheikki kannisto

Ganymede, one of Jupiter’s moons, has the potential to act as a significant dark matter detector, with upcoming space missions possibly unveiling unique dark matter craters on its ancient terrain.

Researchers typically seek dark matter by looking for lightweight particles that seldom interact with normal matter, employing large, insulated underground detectors. Alternatively, another category of dark matter particles could grow from the size of a basketball to that of an asteroid, but these are infrequent and interact rarely with conventional matter. To detect these hefty dark matter particles, a detector of lunar or planetary scale is necessary to account for their scarcity.

William Derocco from the University of Maryland has proposed that Ganymede, the solar system’s largest moon, may hold clues to these large dark matter particles. His research indicates that they could create a unique crater on the moon’s icy surface, preserved for millions of years due to its stable geology.

Derocco estimates the extent to which these giant dark matter particles penetrate Ganymede’s thick ice layers, finding that they reach the subterranean oceans, fostering unique minerals deeper than a standard asteroid might.

Future missions, such as NASA’s Europa Clipper and ESA’s JUICE, might be able to identify these dark material craters from orbit. Derocco believes these features will be relatively small and distinct, separated from other geological formations. He suggests that “if an underground intrusion radar is used, it may reveal this melted ice column extending down through the ice.”

Utilizing a moon-sized dark matter detector could help identify particles that elude detection on Earth, according to Zachary Picker from UCLA. He states, “Experiments on Earth struggle to find dark matter particles the size of a bowling ball. Particles the size of a refrigerator or car have interactions that are too infrequent.”

The proposal is thorough and well-reasoned, as noted by Bradley Cabana from the University of Cantabria in Spain. “There’s no compelling physical rationale to assume the existence of such massive dark matter particles,” he states. “It’s about exploring all possibilities.” He describes these as extraordinary objects, incredibly dense and held together by formidable forces from obscure sectors.

Topics:

Dark matter/
Space exploration

Source: www.newscientist.com

The Eternal Planet Sustains Itself by “Consuming” Dark Matter

Posted on July 21, 2025 by Igor Mitreski

In the heart of the Milky Way, the stars appear younger than expected.

NASA, Caltech, Susan Stolovy (SSC, Caltech)

SEI 259312434 — In the heart of the Milky Way, the stars appear younger than expected.

NASA, Caltech, Susan Stolovy (SSC, Caltech)

Stars in the core of our galaxy may indeed be nearly immortal, harnessing dark matter for energy.

Over two decades ago, astronomers observed oddities among the stars at the Milky Way’s center. Their emitted light suggests they are younger than their mass would indicate; this phenomenon is termed the “Youth Paradox.” Furthermore, there’s a surprising scarcity of older stars in this region, referred to as the “aging difficulty problem.”

Currently, Isabelle John from the University of Stockholm and her team employed computer simulations to propose that dark matter might hold the key to resolving both issues.

It’s established that the centers of galaxies possess high densities of dark matter. The researchers simulated the interactions of dark matter particles with stars and found that upon collision with a star’s atomic nucleus, a particle loses energy and can become trapped there. If other dark matter particles are also present at the same site, they can annihilate each other, generating bursts of energy that illuminate the stars.

Stars typically age due to a lack of fusion fuel, but dark matter could serve as an extra energy source, extending their longevity. Given the substantial amount of dark matter surrounding the galactic center, this mechanism may effectively grant stars a form of immortality, according to John.

She notes that the team’s simulations are based on broad assumptions regarding dark matter and align qualitatively with historical observations. However, further empirical data could enhance our understanding, prompting additional telescope observations to gather fresh insights on dark matter and verify if the stars at the Milky Way’s core can indeed achieve eternal life, as their nature remains poorly understood.

Mark Pinne from Ohio State University emphasizes the importance of interpreting simulations of stars situated away from the galaxy’s center. He points out that since there exists comprehensive observational data on stars near Earth, the anticipated impacts of dark matter should be cross-verified with this information.

Topics:

Source: www.newscientist.com

Dark Dwarfs Could Uncover the True Nature of Dark Matter

Posted on July 8, 2025 by Igor Mitreski

A research team from Durham University, the University of Hawaii, and the University of Liverpool suggests that dark dwarfs are theoretical objects driven by dark matter, created from the cooling process of brown dwarfs.

An AI representation of a dark dwarf. Image credit: Gemini AI.

Currently, we understand that dark matter exists and how it behaves, but we are still unsure of its true nature.

In the last half-century, various theories have emerged, but gathering sufficient experimental evidence remains a challenge.

Some of the most well-known candidates for dark matter include weakly interacting massive particles (WIMPS), which are substantial particles that interact very slightly with ordinary matter. They pass through unnoticed, do not emit light, and reveal themselves only through gravitational effects.

This form of dark matter is essential for the existence of dark dwarfs.

“Dark matter interacts with gravity, allowing it to be captured by stars and accumulate within them,” explained Professor Jeremy Sachstein from the University of Hawaii.

“If this occurs, it may also interact internally, leading to annihilation and energy release that heats the star.”

A nuclear fusion process occurs at the star’s core, generating significant heat and energy, which allows a typical star to shine.

Fusion happens when a star’s mass is sufficient for gravity to compress matter toward the center intensely enough to initiate reactions between the nuclei.

This process releases a tremendous amount of energy, which is perceived as light. Although dark dwarfs also emit light, they do not do so through nuclear fusion.

“Dark dwarfs are low-mass objects, roughly 8% of the solar mass,” noted Professor Sachstein.

“Such small masses are insufficient to trigger a fusion reaction.”

“Consequently, these objects are prevalent in the universe but typically emit only dim light, being classified as brown dwarfs by scientists.

However, if brown dwarfs reside in regions with a high concentration of dark matter (such as the center of the Milky Way), they can evolve into different entities.

“These objects gather dark matter that enables them to transform into dark stars,” Professor Sachstein stated.

“The greater the surrounding dark matter, the more can be captured.”

“And as the dark material accumulates within the star, more energy is generated through its annihilation.”

“For a dark dwarf to exist, dark matter must consist of heavy particles that engage strongly with one another to produce visible matter.”

“Alternative candidates proposed to explain dark matter, such as axions, ambiguous ultralight particles, or sterile neutrinos, are too light to yield the expected effects on these objects.”

“Only massive particles capable of interacting with each other and annihilating to produce visible energy can facilitate the emergence of dark dwarfs.”

However, this hypothesis lacks substantial value without a definitive method of identifying dark dwarfs.

Therefore, Professor Sachstein and his team have suggested distinctive markers.

“There were a few indicators, but lithium-7 presents a unique scenario,” Professor Sachstein mentioned.

“Lithium-7 combusts readily and is rapidly depleted in regular stars.”

“Thus, if you identify an object resembling a dark dwarf, you should search for the presence of lithium, as it would be absent if it were a brown dwarf or something similar.”

The team’s study will be published in Journal of Cosmology and Astroparticle Physics.

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DJUNA CROON et al. 2025. Dark Dwarf: A theoretical dark matter-driven star-like object awaiting discovery at the Galactic Center. jcap 07:019; doi:10.1088/1475-7516/2025/07/019

Source: www.sci.news

Astronomers Map the Distribution of Ordinary Matter Across the Universe

Posted on June 17, 2025 by Igor Mitreski

Astronomers are making significant strides in comprehending how matter behaves and interacts in space utilizing fast radio bursts (FRB). They have found that over three-quarters of the universe’s ordinary material is concealed within sparse intergalactic gases, and they have also identified the furthest FRB event recorded to date.

This artist’s concept illustrates the density regions and red blank areas of the universe’s web in blue. Image Credit: Jack Madden/Illustristng/Ralf Konietzka/Liam Connor, CFA.

For many years, it has been established that at least half of the normal, predominantly proton-based baryonic material in the universe has gone unaccounted for.

Previous approaches by astronomers employed methods like X-ray and ultraviolet observations to gather significant clues regarding this missing mass, which manifests as extremely thin warm gases between galaxies.

The challenge arises from the high-temperature, low-density gas that remains mostly invisible to most telescopes, leaving scientists unable to assess its presence or distribution.

This is where FRBs come into play – brief, intense radio signals emitted by distant galaxies that researchers have recently demonstrated could measure baryonic matter in space, although its location remained a mystery until now.

In the latest study, scientists examined 60 FRBs, with the most distant FRB recorded at 1,174 million light-years (FRB 20200120E) from Messier 81 and reaching up to 9.1 billion light-years (FRB 20230521b).

This enabled them to pinpoint the missing material within intergalactic spaces or the intergalactic medium (IGM).

“The ‘baryon problem’ was never in doubt,” stated Dr. Liam Connor, an astronomer at the Harvard & Smithsonian Center for Astrophysics. “The issue has always been about its location. Now with FRBs, we’ve established that three-quarters of it exists between galaxies in the cosmic web.”

By analyzing the delays in each FRB signal as it traveled through space, Dr. Connor and his colleagues tracked the gaseous medium along its path.

“FRBs function like flashlights in space, illuminating the intergalactic medium. By accurately gauging how the light slows down, we can assess this medium, whether it’s starkly visible or barely detectable,” Dr. Connor explains.

The findings are revealing—approximately 76% of the universe’s baryonic matter resides within the IGM.

Additionally, about 15% is found in galaxy halos, with a minor fraction embedded within stars and cool galactic gases.

This distribution aligns with predictions made by advanced cosmological simulations, yet this is the first instance of direct confirmation.

“This marks a triumph for contemporary astronomy,” noted Dr. Vikram Ravi, an astronomer from California.

“Thanks to FRBs, we are now approaching a new understanding of the universe’s structure and composition.”

“These brief flashes enable us to trace the invisible baryonic matter filling the expansive voids between galaxies,” he added.

“Baryons are pulled into galaxies by gravity; however, supermassive black holes and supernova explosions can expel them back into the IGM, cooling cosmic temperatures when they spiral out of control,” commented Dr. Connor.

“Our findings indicate that this feedback mechanism is effective, suggesting gas must be displaced from galaxies into the IGM.”

The team’s results are published today in the journal Nature Astronomy.

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L. Connor et al. Gas-rich cosmic web unveiled by the partition of missing baryons. Nature Astronomy Published online on June 16th, 2025. doi:10.1038/s41550-025-02566-y

Source: www.sci.news

We Might Have Found the First Star Made of Dark Matter

Posted on June 6, 2025 by Igor Mitreski

Mysterious stars might be fueled by dark matter

Artsiom P/Shutterstock

SEI 254497072 — Mysterious stars might be fueled by dark matter

Artsiom P/Shutterstock

Astronomers have uncovered compelling evidence for the existence of Dark Stars—massive stars in the early universe that might be partly energized by dark matter. If confirmed, these hypothetical stars could shed light on the enigmatic large black holes observed in the early universe, although skepticism remains among some astronomers regarding these findings.

The concept of Dark Stars was proposed in 2007 by Katherine Freese and her colleagues at the University of Texas at Austin. They theorized that immense clouds of hydrogen and helium in the early universe could interact with dark matter, forming gigantic and stable stars. Absent dark matter, such vast gas clouds would collapse into black holes, but energy from decaying dark matter can counter this collapse, resulting in star-like entities even without the nuclear fusion typical of ordinary stars.

Until recently, evidence for these exotic objects from the early universe was scant, but in 2022, the James Webb Space Telescope (JWST) began discovering numerous bright, distant celestial objects. Freese and her team identified three galaxies that exhibited several characteristics predicted by Dark Star models, such as round shapes and similar luminosity, though detailed spectral data was absent to confirm their hypothesis definitively.

Now, with new spectral observations from JWST, Freese’s team believes they can match theoretical predictions of what Dark Stars should resemble, including two additional candidates. One of these potential candidates shows intriguing hints of specific helium characteristics—missing electrons—which, if validated, could serve as a distinct hallmark of a Dark Star. Freese remarks, “If it’s real, I don’t know how else to explain it using Dark Stars.” She cautions, however, that evidence is still limited.

Meanwhile, Daniel Whalen from the University of Portsmouth in the UK suggests that an alternative theory of ultra-massive protostars, which do not involve dark matter, might also explain the JWST findings. “They overlook considerable literature concerning the formation of ultra-massive protostars, some of which can produce signatures remarkably similar to the ones they present,” claims Whalen.

Freese, however, strongly disagrees, asserting that burning dark matter is the only feasible method for creating such massive stars. “There’s no alternative route,” she insists.

A complicating factor arises from separate observations of the objects studied by Freese’s team using the Atacama Large Millimeter Array (ALMA) in Chile, which indicated the presence of oxygen. This element is not associated with Dark Stars, suggesting these candidates might be hybrid stars. On the other hand, Whalen and his team interpret the presence of oxygen as a strong indicator that these objects cannot be Dark Stars, attributing their formation to conventional stars that exploded as supernovae.

Should Freese and her collaborators confirm that these objects are indeed Dark Stars, it could address significant challenges in understanding the universe. Current models posit that such black holes can only originate from extremely massive matter, which raises questions about their formation in the early universe.

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Source: www.newscientist.com

Can universes contain dark matter halos without any galaxies?

Posted on April 9, 2025 by Igor Mitreski

A new study by computational astrophysicist Ethan Nadler from the University of California, San Diego, shows that star formation can occur at halos in the solar masses of 10 million people through molecular hydrogen cooling.

Nadler calculated the percentage of dark matter halos above the critical mass required for star formation. Image credit: Xiaodian Chen.

All galaxies are thought to form at the center of the dark matter halo. This is a region of material coupled to gravity that extends far beyond the galaxy’s visible boundary.

Stars form when gravity within the halo of dark matter draws gases, but astrophysicists still don’t know if there is a dark halo of matter without stars.

“What is the halo mass threshold for the galaxy layer?” said Dr. Nadler.

“This question underlies the key areas of research in galaxy formation and cosmology, including when and how the first galaxy was formed, how galaxies promote the regeneration of the universe, and whether halos of “dark” (without galaxies) exist.

“Robust predictions of galaxy formation thresholds are important to provide future observations of faint galaxies and low-mass halos throughout the history of the universe.”

In his new study, Dr. Nadler calculated the mass that Halo cannot form stars.

His research was conducted using analytical predictions from galaxy formation theory and cosmological simulations.

“Historically, understanding of dark matter has been related to behavior in the galaxy,” Dr. Nadler said.

“When you detect a completely dark halo, a new window opens to study the universe.”

Previously, this threshold for star formation was thought to be between 100 million and 1 billion solar masses due to cooling of atomic hydrogen gas.

The current study shows that star formation can occur in the solar mass of 10 million people at halos via molecular hydrogen cooling.

“The Rubin Observatory will be coming online later this year and Webb is already making unprecedented observations of our universe, so we’ll soon have new data to test these predictions, revealing whether there’s a completely dark halo,” Dr. Nadler said.

“This could have widespread consequences for cosmology and the nature of dark matter.”

study It will be displayed in Astrophysics Journal Letter.

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Ethan O. Nadler. 2025. Effect of molecular hydrogen cooling on galaxy formation thresholds. apjl 983, L23; doi:10.3847/2041-8213/adbc6e

Source: www.sci.news

AI can rapidly decode digital data stored in DNA in a matter of minutes instead of days

Posted on February 21, 2025 by Igor Mitreski

DNA can store digital data such as visual and audio files

Science Picture Co / Alamy

Artificial intelligence can read data stored in DNA strands within 10 minutes, not the day required for previous methods, and DNA storage approaches practical use of computing.

“DNA stores huge amounts of data in a very compact form and remains intact for thousands of years.” Daniella Bar-Lev At the University of California, San Diego. “In addition, DNA is naturally replicable and offers a unique advantage for long-term data storage.”

However, getting encoded information within DNA is a monumental challenge as the strands become confused when mixed and stored. During the data encoding process, individual strands may be replicated incompletely, and some fragments may be lost completely. As a result, data readings stored in DNA are similar to reconstructing books from boxes filled with pages that go beyond the finest, varied.

“The traditional methods suffer from this confusion and require several days of processing,” says Bar-Lev. The new approach “rationalizes this with AI trained to find patterns of noise,” she says.

Bar-Lev and her colleagues developed an AI-driven method called DNAFormer. The system includes a deep learning AI model trained to reconstruct DNA sequences, another computer algorithm to identify and correct errors, and a third decoding that brings everything back to digital data while correcting any remaining mistakes. Includes algorithms.

In experiments, DNAFormer can read 100 megabytes of DNA storage data 90 times faster than the next fastest method developed with traditional rules-based computing algorithms, while achieving better or equivalent accuracy. I did. The decoded data included colored images of the test tube, a 24-second audio clip from astronaut Neil Armstrong's famous Moonlanding speech, and text on why DNA is a promising data storage medium .

The team says they plan to develop a version of DNAFormer tailored to new technologies for encoding data into DNA. Omar Savery Technion – Israel Institute of Technology.

“Crucially, our approach doesn't rely specifically on us. [DNA] Synthesis or sequencing methods can be adapted to future, still undeveloped technologies that are more commercially viable,” he says.

topic:

Source: www.newscientist.com

Investigation: Characteristics of GD-1 Stellar Streams Induced by Self-Interacting Dark Matter Subhaloes

Posted on January 8, 2025 by Igor Mitreski

A self-collapsing, self-interacting dark matter subhalo is a unique spur observed in GD-1, a stellar stream within the Milky Way’s galactic halo, according to a new study led by astronomers at the University of California, Riverside, and is responsible for the gap characteristics.

GD-1 exhibits spur and gap structures that may be attributed to its proximity with a dense substructure. Image credit: University of California, Riverside.

A stellar stream is a group of stars that collectively move along a shared orbit.

A gap refers to a local under-density of stars along the stream, whereas a spur refers to an excess of star density extending outward from the main body of the stream.

Because dark matter governs the movement of star streams, astronomers can use it to track the invisible dark matter in galaxies.

The Milky Way’s halo is a roughly spherical region surrounding our galaxy that contains dark matter and extends beyond the visible edge of our galaxy.

Astronomers discovered that the fulcrum and gap features of the GD-1 star stream cannot easily be attributed to the gravitational influence of the Milky Way’s known globular clusters or satellite galaxies.

However, these features may be explained by unknown perturbing objects such as subhalos.

But the object’s density would need to be significantly higher than that predicted by conventional cold dark matter (CDM) subhalos.

“CDM subhalos typically lack the density necessary to produce the unique features observed in GD-1 streams,” said Haibo Yu, a professor at the University of California, Riverside.

“However, our study shows that a subhalo of collapsing self-interacting dark matter (SIDM) can achieve the required density.”

“Such a compact subhalo would be dense enough to exert the gravitational effects necessary to explain the observed perturbations in the GD-1 flow.”

The currently popular dark matter theory, CDM, assumes that dark matter particles have no collisions.

SIDM, a theoretical form of dark matter, proposes that dark matter particles self-interact through new dark forces.

In the study, Professor Yu and his colleagues used a numerical simulation called N-body simulation to model the behavior of a collapsing SIDM subhalo.

“Our team’s findings provide a new explanation for the lobes and gap features observed on GD-1, long thought to indicate close encounters with dense objects. ” said Professor Yu.

“In our scenario, the perturbation source is the SIDM subhalo, which perturbs the spatial and velocity distribution of stars within the star stream, producing the unique features seen in the GD-1 star stream.”

The discovery also provides insight into the nature of dark matter itself.

“This study opens a promising new avenue to study the self-interaction properties of dark matter through stellar streams,” Professor Yu said.

“This represents an exciting step forward in our understanding of dark matter and the dynamics of the Milky Way.”

The full study will appear in Astrophysics Journal Letter.

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Zhang Xingyu others. 2025. GD-1 Stellar Stream Parter Bar as a self-interacting dark matter halo with a collapsed core. APJL 978, L23; doi: 10.3847/2041-8213/ada02b

Source: www.sci.news

Physicists discover proof of asymmetry between matter and antimatter in decay of baryons and beauty hadrons

Posted on December 19, 2024 by Igor Mitreski

The standard model of particle physics predicts an asymmetry between matter and antimatter known as charge parity (CP) violation. However, the size of this asymmetry in the Standard Model is not large enough to explain the disequilibrium, and so far the asymmetry has only been observed in certain decays of particles called mesons. In two new studies, LHCb collaboration CERN’s Large Hadron Collider (LHC) has discovered evidence of CP violation in baryon decay and beauty hadron decay into charmonium particles, shedding light on these two pieces of the matter-antimatter puzzle.

Exterior view of the LHCb detector. Image credit: CERN.

Experiments involving LHCb have previously searched for baryon CP violation by looking for differences in the way matter and antimatter baryons decay into other particles.

However, these investigations have so far been essentially empty-handed.

One LHCb study provided evidence for a process in the specific collapse of the bottom lambda baryon, but subsequent studies analyzing larger samples of such collapses did not increase that evidence.

in first new studyLHCb physicists scrutinized proton-proton collision data obtained during the first and second runs of the LHC and discovered various decay modes of the bottom lambda baryon, including decay into a lambda baryon and two kaons. You have searched for

We then investigated the CP violation in each decay mode, essentially by counting the number of decays of the bottom lambdabaryon and its antimatter partner and taking the difference between the two.

In the case of the lambda baryon and its decay into two kaons, this difference showed evidence of a CP violation with a significance of 3.2 standard deviations.

in second studythe LHCb team focused on the decay of a beautiful charged meson into J/psi and a charged pion.

J/psi is a charmmonium particle, a meson consisting of a charm quark and a charm antiquark.

We performed an analysis similar to the lower lambda baryon study, also using data from the first and second runs of the LHC, and found evidence for CP violation in this decay mode of charged meons. Again, the significance is 3.2 standard. Deviation.

This finding represents evidence of CP violation in the decay of beauty hadrons to charmonium particles.

“Our study represents an important step toward establishing whether CP violations are present in these types of collapses,” the authors state.

“Data from the high-luminosity LHC, with its third experiment and planned collider upgrades, will shed further light on these and other parts of the matter-antimatter puzzle. .”

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LHCb collaboration. 2024. Study of Λ0b and Ξ0b decay to Λh+h'- and evidence of CP violation in Λ0b→ΛK+K- decay. arXiv: 2411.15441

LHCb collaboration. 2024. First evidence of direct CP violation to charmonium decay in cosmetology. arXiv: 2411.12178

Source: www.sci.news

Astrophysicists study planets, asteroids, and primordial black holes in Earth’s matter

Posted on December 3, 2024 by Igor Mitreski

Primordial black holes have been theorized for decades and may even be the eternally elusive dark matter. However, primordial black holes have not yet been observed. These tiny black holes could become trapped in rocky planets or asteroids, consuming their liquid cores from within and leaving hollow structures behind, according to a duo of astrophysicists from the University at Buffalo, Case Western Reserve University, and National Donghua University. It is said that there is. Alternatively, microtunnels could be left in very old rocks on Earth, or in the glass or other solid structures of very old buildings.

An artist's impression of a primordial black hole. Image credit: NASA.

Small primordial black holes are perhaps the most intriguing and intriguing relics of the early universe.

They could act as candidates for dark matter, be sources of primordial gravitational waves, and help solve cosmological problems such as domain walls and the magnetic monopole problem.

However, so far no convincing primordial black hole candidates have been observed.

Professor Dejan Stojković of the University at Buffalo said: “Although the chances of finding these signatures are low, the search does not require many resources and the potential reward of providing the first evidence of a primordial black hole is enormous. It's going to become something.”

“We need to think outside the box because what has been done so far to find primordial black holes has not worked.”

Professor Stojkovic and colleague Dr. De Zhang Dai, of Case Western Reserve University and National Donghua University, are investigating how large hollow asteroids can grow without collapsing, and whether a primordial black hole is The probability of passing was calculated. Earth.

“Because of such long odds, we have focused on hard traces that have existed for thousands, millions, or even billions of years,” Dr. Dai said. .

“If the object has a liquid central core, a trapped primordial black hole could absorb the liquid core, whose density is higher than that of the outer solid layer,” Professor Stojković added.

“In that case, if the object was hit by an asteroid, the primordial black hole could escape from the object, leaving only a hollow shell.”

But would such a shell be strong enough to support itself, or would it simply collapse under its own tension?

Comparing the strength of natural materials such as granite and iron to their surface tension and surface density, the researchers found that such hollow objects could be less than one-tenth the radius of the Earth, making them smaller than normal We calculated that it was more likely to be an asteroid than a planet. .

“If it gets any bigger, it will collapse,” Professor Stojković said.

“These hollow objects could potentially be detected with telescopes. The mass, and therefore the density, can be determined by studying the objects' trajectories.”

“If an object's density is too low for its size, that's a good sign that it's hollow.”

For objects without a liquid core, the primordial black hole could simply pass through, leaving a straight microtunnel behind.

For example, a primordial black hole with mass 10^{twenty two} grams, leaving a tunnel 0.1 microns thick.

Large slabs of metal or other materials could serve as effective black hole detectors by monitoring the sudden appearance of these tunnels, but very old materials from buildings that are hundreds of years old Searching for existing tunnels has a higher probability. From the oldest to rocks that are billions of years old.

Still, even assuming that dark matter is indeed composed of primordial black holes, they calculated that the probability that a primordial black hole would pass through a billion-year-old rock is 0.000001.

“You have to compare costs and benefits. Does it cost a lot of money to do this? No, it doesn't,” Professor Stojković said.

“So, to say the least, it's unlikely that a primordial black hole will pass through you during your lifetime. Even if you did, you probably wouldn't notice.”

“Unlike rocks, human tissue has a small amount of tension, so the primordial black hole won't tear it apart.”

“And while the kinetic energy of a primordial black hole may be huge, it is moving so fast that it cannot release much of that energy during a collision.”

“If a projectile is moving through a medium faster than the speed of sound, the molecular structure of the medium has no time to react.”

“If you throw a rock through a window, it will probably break. If you shoot a window with a gun, it will probably just leave a hole.”

team's paper Published in a magazine physics of the dark universe.

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De Chan Dai and Dejan Stojković. 2024. We're looking for planets, asteroids, and tiny primordial black holes on Earth. physics of the dark universe 46: 101662;doi: 10.1016/j.dark.2024.101662

Source: www.sci.news

Physicists Find Indications of Superfluidity in Low-Density Neutronic Matter

Posted on November 12, 2024 by Igor Mitreski

Accurate description of low-density nuclear matter is critical to explaining the physics of the neutron star’s crust, according to a team of theoretical physicists led by Argonne National Laboratory. Dr. Alessandro Lovato.

Fore others. We study the crust of neutron stars by simulating neutron matter and then adding “hidden” neutrons that mediate interactions between “real” neutrons. The neural network then constructs quantum wave functions for the normal and superfluid phases of neutronic matter. Image credit: Jane Kim, Ohio University.

The inner crust of a neutron star is characteristic Due to the existence of neutron superfluid.

A superfluid is a fluid that has no viscosity. In a neutron star, this means that the superfluid allows neutrons to flow without resistance.

To accurately predict the properties of neutronic matter at the lowest energy levels in this low-density form, researchers typically perform theoretical calculations that assume that neutrons combine to form Cooper pairs.

“The low-density nuclear material found in the crust of neutron stars exhibits complex and interesting structures that vary greatly with density,” Lovato and colleagues said.

“In the outer shell, the nucleons are bound to fully ionized nuclei. As the density increases within this region, these nuclei become increasingly neutron-rich, so in ground-based experiments they are present at lower densities. It is only possible to directly determine the main nuclides that

physicist used Artificial neural networks do not rely on this assumption to make accurate predictions.

They modified the standard “single particle” approach by introducing “hidden” neutrons that facilitate interactions between “real” neutrons and encode quantum many-body correlations.

This allows Cooper pairs to appear naturally during calculations.

“Understanding neutron superfluidity provides important insights into neutron stars,” the researchers said.

“This reveals phenomena such as its cooling mechanisms, rotation, and sudden changes in rotational speed.”

“Although we cannot directly access neutron star material experimentally, the fundamental interactions that govern the behavior of this material are the same as those that govern the nuclei of atoms on Earth.”

“Researchers are working to create simple yet predictable nuclear interactions.”

“Solving the quantum many-body problem accurately is an important part of assessing the quality of these interactions.”

“Our study uses simple interactions that are in good agreement with previous calculations that assumed more complex interactions.”

Low-density neutronic matter is characterized by fascinating emergent quantum phenomena, such as the formation of Cooper pairs and the onset of superfluidity.

“We used a combination of artificial neural networks and advanced optimization techniques to study this dense region,” the scientists said.

“Using a simplified model of the interaction between neutrons, we calculated the energy per particle and compared the results with those obtained from very realistic interactions.”

“This approach is competitive compared to other computational techniques at a fraction of the cost.”

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Bryce Foer others. 2024. Investigating the crust of a neutron star with the quantum state of a neural network. arXiv: 2407.21207

Bryce Foer others. 2023. Diluting neutron star material from quantum states in neural networks. Physics. Rev. Research 5(3):033062;doi: 10.1103/PhysRevResearch.5.033062

Source: www.sci.news

This Surprising Find in the Universe Could Finally Unlock the Dark Matter Mystery

Posted on October 4, 2024 by Igor Mitreski

Evidence of antimatter in cosmic rays has been discovered by scientists, suggesting the potential existence of a new type of particle. These particles could be a part of dark matter, a mysterious substance that makes up 85 percent of the universe’s mass but has never been directly observed.

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A recent study indicates that antihelium particles, the antimatter form of helium, detected by instruments on the International Space Station may have originated from a new class of weakly interacting massive particles (WIMPs). It is believed that dark matter could be made up of WIMPs.

“WIMP is a theoretical particle that could potentially be a perfect candidate for dark matter,” explained lead author Pedro de la Torre Luque, a physicist supporting research at the Institute of Theoretical Physics in Madrid. “Many proposed models have been ruled out, leaving only a few surviving theories.”

The antihelium core observed during cosmic ray research on the space station’s alpha magnetic spectrometer (AMS-02) may have been the result of two WIMPs colliding and annihilating each other. This collision could have generated matter, antimatter, and energy.

Antimatter is essentially the “mirror image” of normal matter, with the same mass but opposite properties such as charge.

While some antimatter may have been created during the Big Bang, researchers believe that additional antimatter is continuously generated by specific cosmic events, although it is challenging to observe.

“The observation of antihelium was thrilling because it indicates an unusual phenomenon occurring in the interstellar medium, where the production of antiparticles is unexpected,” stated De La Torre Luque.

“Theoretical forecasts suggest that even though cosmic rays interact with interstellar gas to produce antiparticles, the presence of antinuclei, particularly antihelium, should be extremely rare.”

“We anticipated discovering an antihelium event once every few decades, but the approximately 10 antihelium events observed by AMS-02 resulted from standard cosmic ray interactions. Therefore, these antihelium occurrences provide a promising clue to WIMP annihilation.”

Read more:

Source: www.sciencefocus.com

Huge Search Yields Zero Results, Dealing Another Blow to Dark Matter

Posted on August 26, 2024 by Igor Mitreski

Sensor array for the LUX-ZEPLIN dark matter experiment in South Dakota

Matthew Kapust/Sanford Underground Research Facility

The latest search for dark matter has so far been fruitless, but the good news is that it has allowed physicists to place the toughest constraints yet on the properties of this mysterious substance. New measurements from the LUX-ZEPLIN (LZ) experiment in South Dakota mean that we are closer than ever to finding dark matter particles, or that we have refuted the most likely explanation.

Dark matter is invisible to the naked eye because it does not interact significantly with normal matter or light. We only know that dark matter exists through its gravitational effects, which tell us that it makes up more than 80 percent of all matter. The leading explanation for dark matter has been that it is composed of weakly interacting massive particles (WIMPs), but searches for these fundamental entities have yet to turn up anything.

LUX-ZEPLIN is a dark matter detector made of seven tonnes of liquid xenon buried 1.5 kilometres underground and is the most sensitive to date, but after 280 days of searching it has yet to find any WIMPs. “We are number one in the world at not finding dark matter,” says an LZ spokesman. Chamkaur Gag At University College London.

While this result may seem disappointing, it allows physicists to place tight constraints on the nature of dark matter, narrowing the range of properties it could have. The constraints are nearly five times tighter than the best known, significantly limiting the possibility of WIMPs. The work was presented at two physics conferences. TeV Particle Astrophysics In the United States lysine It will be held in Brazil on August 26th.

“It’s like they say there’s a magic fish in the ocean, but we don’t know where it is,” Gag says. “You go in and swim around, you get out, you snorkel around, and you still don’t find it, so you use a submarine.” If the magic fish is a WIMP, he says, researchers have explored about 75 percent of the oceans and still haven’t found it.

“This is the next big step forward, one in a long line of such steps.” Dan Hooper “It’s probably fair to say that at any of these steps forward we can’t expect to see anything, but it doesn’t seem unlikely that we’ll see something if we take enough of these steps,” said David G. Schneider, a researcher at Fermi National Accelerator Laboratory in Illinois who was not involved in the study.

At this point, many of the initially popular ideas for possible types of WIMPs have been ruled out. There are still a few left, but LZ isn’t done yet. It plans to observe for a total of 1,000 days before wrapping up in 2028. “If LZ doesn’t detect a WIMP, and our next-generation detector, XLZD, doesn’t detect a WIMP, then WIMPs are over,” Gag says. The XLZD project is still in the planning stages.

If WIMPs don’t constitute dark matter, it would be a major paradigm shift, but physicists aren’t giving up on finding dark matter entirely. “If you’re trying to solve a murder investigation and you have 20 suspects, 10 of them are unaware,” he says. [alibis]”We don’t go, ‘Oh, it looks like it wasn’t a murder.’ We just get a better idea of who the right suspects are,” Hooper said. “We take some suspects off our list, we narrow the scope of the investigation, we narrow the focus. That’s what progress looks like in this field.”

topic:

Source: www.newscientist.com

Astronomers witness the split of dark and regular matter in the clash of two galaxy clusters

Posted on August 1, 2024 by Igor Mitreski

The two galaxy clusters, known as MACS J0018.5+1626, contain thousands of galaxies each and are located billions of light-years away from Earth. As the clusters hurtled towards each other, dark matter traveled faster than normal matter.

This artist's conceptual illustration shows what happened when two massive clusters of galaxies, collectively known as MACS J0018.5+1626, collided. The dark matter (blue) in the clusters moves ahead of the associated hot gas clouds, or regular matter (orange). Both dark matter and regular matter feel the pull of gravity, but only the regular matter experiences additional effects like shocks and turbulence that slow it down during the collision. Image courtesy of W. M. Keck Observatory/Adam Makarenko.

Galaxy cluster mergers are a rich source of information for testing the astrophysics and cosmology of galaxy clusters.

However, the coalescence of clusters produces complex projection signals that are difficult to physically interpret from individual observation probes.

“Imagine a series of sand-carrying dump trucks colliding, and the dark matter would fly forward like sand,” says astronomer Emily Silich of the California Institute of Technology and the Harvard-Smithsonian Center for Astrophysics.

This separation of dark matter and normal matter has been observed before, most famously in the Bullet Cluster.

In this collision, hot gas can be clearly seen lagging behind dark matter after the two galaxy clusters push through each other.

The situation that occurred in MACS J0018.5+1626 is similar, but the direction of the merger is rotated about 90 degrees relative to the direction of the Bullet Cluster.

In other words, one of the giant galaxy clusters in MACS J0018.5+1626 is flying almost straight towards Earth, while the other is moving away.

This orientation gave the researchers a unique perspective to map the speeds of both dark and normal matter for the first time, and unravel how they separate during galaxy cluster collisions.

“Bullet Cluster makes you feel like you're sitting in the stands watching a car race, taking beautiful snapshots of cars moving from left to right on a straight stretch of road,” said Jack Sayers, a professor at the California Institute of Technology.

“For us, it's like standing in front of an oncoming car on a straight stretch of road with a radar gun and measuring its speed.”

To measure the velocity of ordinary matter, or gas, in galaxy clusters, the astronomers used an observational technique known as the kinetic Sunyaev-Zel'dovich (SZ) effect.

In 2013, they made the first observational detection of the kinetic SZ effect on an individual cosmic object, a galaxy cluster named MACS J0717.

The kinetic SZ effect occurs when photons from the early universe, or the cosmic microwave background radiation (CMB), are scattered by electrons in hot gas on their way to Earth.

Photons undergo a shift called the Doppler shift due to the movement of electrons in the gas cloud along the line of sight.

By measuring the change in brightness of the CMB due to this shift, astronomers can determine the speed of the gas clouds within the cluster.

By 2019, the study authors had made these motional SZ measurements in several galaxy clusters to determine the velocity of the gas, or ordinary matter.

They also measured the speed of galaxies within the cluster, which gave them an indirect idea of the speed of dark matter.

However, at this stage of the study, our understanding of the cluster orientation was limited.

All they knew was that one of them, MACS J0018.5+1626, was showing signs of something strange going on: hot gas, or regular matter, moving in the opposite direction to dark matter.

“We saw a totally strange phenomenon where the velocities were in opposite directions, which initially made us think there might be a problem with the data,” Prof Sayers said.

“Even our colleagues simulating galaxy clusters had no idea what was going on.”

Scientists then used data from NASA's Chandra X-ray Observatory to determine the temperature and location of the gas in the cluster, as well as the extent to which it is being bombarded.

“These cluster collisions are the most energetic events since the Big Bang,” Šilić said.

“Chandra will measure the extreme temperatures of the gas, which will tell us the age of the merger and how recently the galaxy cluster collision took place.”

The authors found that before the collision, the clusters were moving towards each other at about 3,000 kilometers per second, roughly 1 percent of the speed of light.

With a more complete picture of what's going on, they were able to work out why dark matter and normal matter appear to be moving in opposite directions.

They say it's hard to visualize, but the direction of the collision, combined with the fact that dark matter and normal matter separated from each other, explains the strange speed measurements.

It is hoped that more studies like this one will be conducted in the future, providing new clues about the mysterious properties of dark matter.

“This work is a starting point for more detailed studies into the nature of dark matter,” Šilić said.

“We now have a new type of direct probe that shows us how dark matter behaves differently from ordinary matter.”

of Investigation result Published in Astrophysical Journal.

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Emily M. Silich others. 2024. ICM-SHOX. I. Methodology overview and discovery of gas-dark matter velocity separation in the MACS J0018.5+1626 merger. ApJ 968, 74; doi: 10.3847/1538-4357/ad3fb5

This article is a version of a press release provided by Caltech.

Source: www.sci.news

Experiments in Basic Physics Could Uncover Hidden Dark Matter in Additional Dimensions

Posted on July 10, 2024 by Igor Mitreski

We don’t tend to dwell on the fact that we exist in three dimensions. Front to back, left to right, up to down – these are the axes along which we move through the world. When we try to imagine something else, we usually conjure up the most outlandish science fiction images of portals in the fabric of space-time and parallel universes.

But serious physicists have long been fascinated by the possibility of extra dimensions. Despite their intangibility, extra dimensions hold the promise of solving some big questions about the deepest workings of the universe. And just because they’re hard to imagine and even harder to observe doesn’t mean we can rule them out. “There’s no reason they have to be three-dimensional,” says David Schneider, a physics professor at the University of California, San Diego. Georges Obie At Oxford University. “It could have been two, it could have been four, it could have been ten.”

Still, there comes a time when any self-respecting physicist wants hard evidence. That’s why it’s so exciting that over the past few years, researchers have developed several techniques that may finally provide evidence of extra dimensions. For example, we might be able to detect gravity leaking into extra dimensions. We might see subtle signatures of it in black holes, or we might find its signature in particle accelerators.

But now, in an unexpected twist, Ovid and his colleagues claim that there is an extra dimension that is fundamentally different from any previously conceived. This “dark dimension” hides ancient particles whose gravity could solve the mystery of dark matter, the force that is thought to have shaped the universe. Crucially, this dimension is relatively…

Source: www.newscientist.com

The importance of passwords in the AI era: Why they still matter | Apple

Posted on June 11, 2024 by Igor Mitreski

AI, whether it stands for artificial intelligence or Apple intelligence, is a hot topic today. It’s time to have a conversation about it. [sits backwards on chair] password.

One significant change coming to Apple’s platform next year is the creation of a new Password app. This was somewhat overshadowed by the reporting from last night’s Apple event in Cupertino and New York by Kari Paul and Nick Robbins-Early.

9to5Mac reports that the new passwords app on iPhone home screens this fall will enhance the security of computing for average users who may not be familiar with password management apps.

The new Passwords app consolidates and simplifies existing password features on iOS and macOS, making them more accessible to users. It will display a list of all user logins after verifying identity.

Apple has expanded its password management capabilities over the years, offering security audits, alerting users to compromised passwords, sharing options, and data import/export features.

The focus on identity, rather than just passwords, highlights Apple’s aim with the new Passwords app. Managing digital identity remains a challenge, with passwords serving as the primary method of online identity verification but coming with inherent security risks.

Password managers like 1Password have emerged as a solution, but the industry is exploring alternatives like passkeys to address the limitations of traditional password systems.

While passkeys promise a password-free future, their adoption has been slow due to limited support from websites and initial user challenges. Despite the potential benefits, concerns remain about the security and user experience of passkeys.

From password managers to passkeys, the quest for secure and user-friendly authentication methods continues.

The evolution of identity verification extends beyond passwords to technologies like AI avatars. While the concept of AI systems participating in meetings remotely is not yet fully realized, advancements in voice synthesis and AI present new challenges and opportunities for digital identity verification.

As technology progresses, ensuring secure and seamless identity verification methods remains a crucial aspect of digital life.

The Wider TechScape

European brown bears play in the pool at Bristol Zoo’s Wild Place Project in 2020.

Source: www.theguardian.com

Galactic anomalies suggesting dark matter presence are more puzzling than anticipated

Posted on May 1, 2024 by Igor Mitreski

A dark matter halo (yellow) forms around the galaxy

Ralph Koehler/SLAC National Accelerator Laboratory

When you think of the Milky Way, “delicate” may not be the first word that comes to mind.But when Mariangela Lisanti She started tinkering with the Our Galaxy recipe, but found it surprisingly fragile.

Lisanti, a particle physicist at Princeton University, wonders what would happen if dark matter, a mysterious substance thought to make up more than 80 percent of all matter in the universe, was more exotic than researchers usually assume. I was simulating something. She replaced a small portion of standard dark matter with something more complex. “We thought we could just add 5% and everything would be fine,” she says. “And we destroyed the galaxy.”

There are good reasons for such interference. Since the 1980s, astronomical signs have shown that dark matter is a single type of slow-moving particle that does not interact with itself. Particle physicists have spent a great deal of effort searching for that particle. But decades later, it remains a no-show. Perhaps because dark matter is not what we tend to imagine.

Recently, a series of galactic anomalies have sparked a scramble to find alternatives. This “complex” dark matter can be as simple as subatomic particles bouncing off each other, or as complex as dark particles forming dark atoms, stars, and even galaxies. There are a number of mind-boggling possibilities.

But now observations of anomalies in our galaxy promise to finally help narrow down the options. and…

Source: www.newscientist.com

New computer model provides evidence for dark matter hypothesis

Posted on April 30, 2024 by Igor Mitreski

A new study led by the University of California, Irvine, addresses a fundamental debate in astrophysics: the existence of invisible dark matter is necessary to explain how the universe works. Is there an observation, or can physicists explain how things work based only on matter that we can know directly?

Dark photons are hypothetical dark sector particles that have been proposed as force carriers, similar to electromagnetic photons but potentially related to dark matter. Image credit: University of Adelaide.

“Our paper shows how a real-world observed relationship can be used as a basis for testing two different models for describing the universe,” said Dr. One Dr. Francisco Mercado said:

“We conducted robust tests to distinguish between the two models.”

“This test required us to run computer simulations using both types of matter, normal matter and dark matter, to account for the presence of interesting features measured in real galaxies.”

“The features we discovered in galaxies would be expected to appear in a universe with dark matter, but would be difficult to explain in a universe without dark matter.”

“We have shown that such features appear in observations of many real galaxies. If we take these data at face value, the dark matter model is the one that best explains the universe we live in. It is reconfirmed that.”

These features explain patterns in the movement of stars and gas within galaxies that appear to be possible only in a universe with dark matter.

“The observed galaxies appear to follow a close relationship between the matter we see and the dark matter we inferred to detect, hence what we call dark matter. Some have even suggested that this is actually evidence that our theory of gravity is wrong,'' New York University said. Professor James Block of Irvine, California;

“What we have shown is that dark matter not only predicts that relationship, but for many galaxies it can explain what we see more naturally than modified gravity.”

“I am even more convinced that dark matter is the correct model.”

This feature has also appeared in observations by proponents of a dark matter-free universe.

“The observations we looked at, the very observations that discovered these features, were made by proponents of the no-dark-matter theory,” said Dr. Jorge Moreno, a researcher at Pomona College. Ta.

“Despite their obvious existence, there has been little analysis of these functions by the community.”

“We needed scientists like us who work with both ordinary matter and dark matter to start the conversation.”

“We hope that this study will spark a debate within our research community, but such features can only be found in our planet if both dark matter and normal matter are present on Earth.” We also found that it appears in simulations, so there may be room for commonalities in the universe. “

“When stars are born and die, they explode into supernovae, which can form the centers of galaxies, providing a natural explanation for the existence of these features.”

“Simply put, the features we investigated in our observations require both the presence of dark matter and the incorporation of normal matter physics.”

Now that the dark matter model of the universe appears to be a promising model, the next step is to see whether it remains consistent across the dark matter universe.

“It will be interesting to see if this same relationship can even be used to distinguish between different dark matter models,” Dr. Mercado said.

“Understanding how this relationship changes under individual dark matter models could help constrain the properties of dark matter itself.”

of paper Published online on Royal Astronomical Society Monthly Notices.

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Francisco J. Mercado other. Hooks and bends in the radial acceleration relationship: Discrimination test between dark matter and MOND. MNRAS 530 (2): 1349-1362; doi: 10.1093/mnras/stae819

Source: www.sci.news

Physicists suggest that the capture and annihilation of dark matter could reignite dormant neutron stars

Posted on April 5, 2024 by Igor Mitreski

A team of particle physicists from the University of Melbourne, Australian National University, King’s College London, and Fermi National Accelerator Laboratory has discovered that the energy transferred when dark matter particles collide and annihilate inside a cold neutron star. They calculated that the star could be heated rapidly. Previously, this heating was thought to be irrelevant because this energy transfer takes a very long time, in some cases longer than the age of the universe itself.

An artist’s impression of a neutron star.

A number of recent studies have focused on trapping dark matter in neutron stars as sensitive probes of the interaction of dark matter with ordinary matter.

This could potentially be used to test dark matter interactions in a way that is highly complementary to experiments on Earth, especially since dark matter is accelerated to relativistic speeds during a fall into a neutron star. there is.

In some cases, neutron star technology may be able to probe interactions that are difficult or impossible to observe with direct dark matter detection experiments. These include dark matter, which is too light to leave a detectable signal in nuclear recoil experiments, and interactions where non-relativistic scattering cross sections are momentum suppressed.

It was recently pointed out that an isolated old neutron star near the Sun could be heated by the capture of dark matter, increasing its temperature by 2000 K.

Once older than 10 million years, an isolated neutron star is expected to cool to temperatures below this unless reheated by standard matter accretion or internal heating mechanisms.

As a result, observations of local neutron stars may place severe constraints on dark matter interactions. Importantly, neutron stars with temperatures in this range produce near-infrared radiation that could be detected by future telescopes.

“Our new calculations show for the first time that most of the energy is stored in just a few days,” said Professor Nicole Bell from the University of Melbourne, lead author of the study.

“The search for dark matter is one of science’s greatest detective stories.”

“Dark matter makes up 85% of the matter in the universe, but we can’t see it.”

“It doesn’t interact with light. It doesn’t absorb, reflect, or emit light.”

“This means that even if we know it exists, we can’t directly observe it with our telescopes.”

“Rather, its attraction to an object that we can see tells us that it must be there.”

“Predicting dark matter theoretically and observing it experimentally are two different things.”

“Earth-based experiments are limited by the technical challenges of building a large enough detector.”

“But neutron stars act as huge natural dark matter detectors, collecting dark matter over astronomically long timescales, so they are a good place to focus our efforts.”

“Neutron stars form when supermassive stars run out of fuel and collapse,” Professor Bell said.

“They have a similar mass to our sun and are squeezed into a sphere just 20km wide. If they got any denser, they would become black holes.”

“Dark matter is the main type of matter in the universe, but it is very difficult to detect because it interacts very weakly with normal matter.”

“In fact, dark matter is so weak that it can pass straight through the Earth and even the Sun.”

“But neutron stars are different. Because neutron stars are so dense, dark matter particles are much more likely to interact with the star.”

“If dark matter particles collide with neutrons inside a star, they lose energy and become trapped.”

“Over time, this will lead to an accumulation of dark matter within the star.”

“We expect this to cause old, cold neutron stars to heat up to a point where they can be observed in the future, or even cause the star to collapse into a black hole,” said the University of Melbourne doctor. candidate Michael Vilgat, co-author of the study.

“If the energy transfer happens quickly enough, the neutron star will heat up.”

“For this to happen, the dark matter would have to collide within the star many times, transferring more and more of the dark matter’s energy until all the energy is stored in the star.”

“Until now it was unknown how long this process takes, because as dark matter particles become less and less energetic, they become less and less likely to interact again.”

“As a result, it was thought that it would take a very long time to transfer all the energy, in some cases longer than the age of the universe.”

Instead, the researchers calculated that 99% of the energy is transferred in just a few days.

“This is good news, because it means dark matter can potentially heat neutron stars to detectable levels,” Birgat said.

“As a result, observations of cold neutron stars will provide important information about the interactions between dark matter and ordinary matter and shed light on the nature of this elusive matter.”

“If we are to understand the ubiquity of dark matter, it is important to use every technology at our disposal to understand what the hidden matter in our universe actually is.” .”

of study Published in Journal of Cosmology and Astroparticle Physics.

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Nicole F. Bell other. 2024. Thermalization and extinction of dark matter in neutron stars. JCAP 04,006; doi: 10.1088/1475-7516/2024/04/006

Source: www.sci.news

Astrophysicist declares universe devoid of dark matter

Posted on March 20, 2024 by Igor Mitreski

Professor Rajendra Gupta of the University of Ottawa is challenging current theoretical models of the composition of the universe by showing that there is actually no room for dark matter in the universe.

This artist's impression shows the evolution of the universe, starting with the Big Bang on the left and continuing with the emergence of the Cosmic Microwave Background. The formation of the first stars ends the Dark Ages of the universe, followed by the formation of galaxies. Image credit: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

In cosmology, the term dark matter refers to anything that does not appear to interact with light or electromagnetic fields, or that can only be explained by gravity.

Although we can't see it and don't know what it's made of, it helps us understand how galaxies, planets, and stars work.

Professor Gupta reached this conclusion using a combination of covariation coupling constant (CCC) and “tired light” (TL) theory (CCC+TL model).

His model combines two ideas: how the forces of nature diminish over cosmic time and that light loses energy as it travels long distances.

It has been tested and shown to be consistent with several observations, including how galaxies spread and how light from the early universe evolved.

The discovery challenges the common understanding of the universe, which suggests that about 27% of the universe is made up of dark matter, less than 5% is normal matter, and the rest is dark energy.

“This new discovery confirms previous research, which found that the universe is 26.7 billion years old, and found that the existence of dark matter is not necessary for the universe,” said Gupta. the professor said.

“Standard cosmology says that the accelerating expansion of the universe is caused by dark energy, but it's actually because the forces of nature weaken as the universe expands, not by dark energy.”

In his research, Professor Gupta analyzed data from a recent paper on the distribution of galaxies at low redshifts and the angular size of the sound horizon in the literature at high redshifts.

“There are several papers that question the existence of dark matter, but to my knowledge, my paper does not support the existence of dark matter, while being consistent with the major cosmological observations that we have had time to confirm.” “This is the first paper to exclude ,” he said.

“By challenging the need for dark matter in the universe and providing evidence for a new cosmological model, this study opens up new avenues for exploring the fundamental properties of the universe.”

of paper Published in astrophysical journal.

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Rajendra P.Gupta other. 2024. Testing the CCC+TL cosmology with observed baryon acoustic vibration signatures. APJ 964, 55; doi: 10.3847/1538-4357/ad1bc6

Source: www.sci.news

Huge Neutron Stars Could Have Cores Composed of Unconfined Quark Matter

Posted on December 28, 2023 by Igor Mitreski

The core of a neutron star contains the highest density of matter in the universe. This highly compressed matter can undergo a phase transition in which nuclear matter dissolves into unconfined quark matter, releasing its constituent quarks and gluons. However, it is currently unknown whether this transition occurs inside at least some physical neutron stars. In a new study, physicists from the University of Helsinki, the University of Stavanger, the Flatiron Institute, and Columbia University quantified this possibility by combining information from astrophysical observations and theoretical calculations.

Artist's impression of a neutron star. Image credit: Sci.News.

Neutron stars are extreme astrophysical objects containing the densest matter found in the modern universe.

It has a radius of about 10 km (6 miles) and a mass of about 1.4 solar masses.

“A long-standing unresolved question concerns whether the enormous central pressure of a neutron star can compress protons and neutrons into a phase called cold quark matter. In this exotic state, individual protons and neutrons no longer exist. We don’t,” said Professor Aleksi Vuorinen of the University of Helsinki.

“The quarks and gluons that make them up are instead freed from typical color confinement and can move almost freely.”

In a new paper, Professor Vuorinen and colleagues provide the first quantitative estimate of the possibility of a core of quark matter existing inside a massive neutron star.

They showed that quark matter is almost inevitable in the most massive neutron stars, based on current astrophysical observations. The quantitative estimates they extracted put the likelihood in the 80-90% range.

For there to be a small chance that all neutron stars are composed only of nuclear matter, the change from nuclear matter to quark matter must occur through a strong primary phase similar to the phenomenon in which liquid water turns to ice. Must be a metastasis.

This type of rapid change in the properties of neutron star matter could destabilize the star in such a way that even the formation of a tiny quark matter core could cause the star to collapse into a black hole.

An artist's impression of the various layers inside a giant neutron star. The red circle represents a significant amount of quark matter core. Image credit: Jyrki Hokkanen, CSC.

“A key element in deriving the new results is a series of large-scale supercomputer calculations that utilize Bayesian inference, a branch of statistical deduction that estimates the likelihood of various model parameters through direct comparison with observed data. “, the authors explained.

“We demonstrate that the Bayesian component allows us to derive new limits on the properties of neutron star matter, approaching the so-called conformal behavior near the center of the most massive and stable neutron stars.”

Dr. Joonas Nettila from the University of Helsinki added: “It is interesting to see specifically how each new neutron star observation improves the ability to estimate the properties of the neutron star material.” .

“Being able to compare theoretical predictions with observations and constrain the possibility of quark-matter nuclei requires hundreds of supercomputers,” said Jonas Hirvonen, a doctoral student at the Flatiron Institute and Columbia University. “We had to spend tens of thousands of CPU hours.”

“We are very grateful to the Finnish Supercomputer Center CSC for providing us with all the necessary resources.”

of paper It was published in the magazine nature communications.

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E.Annara other. 2023. Strongly interacting matter exhibits unconfined behavior in massive neutron stars. Nat Commune 14, 8451; doi: 10.1038/s41467-023-44051-y

Source: www.sci.news

Astrophysical mysteries unraveled by new dark matter theory

Posted on December 17, 2023 by Igor Mitreski

Researchers have advanced our understanding of dark matter through simulations that support the self-interacting dark matter (SIDM) theory. This theory has the potential to resolve the discrepancy in dark matter density observed in different galaxies, poses a challenge to traditional cold dark matter (CDM) models, and highlights the dynamic nature of dark matter. Credit: SciTechDaily.com

Dark matter may be more active than previously thought, reports a study from the University of California, Riverside.

Dark matter, which is thought to make up 85% of the matter in the universe, does not emit light and its properties are still poorly understood. Normal matter absorbs, reflects, and emits light, but dark matter cannot be seen directly, making it difficult to detect. A theory called “self-interacting dark matter” (SIDM) claims that dark matter particles self-interact with each other due to dark forces, causing them to collide strongly with each other near the centers of galaxies.

Among the works published in of Astrophysics Journal LetterA research team led by Haibo Yu, a professor of physics and astronomy at the University of California, Riverside, reports that SIDM can simultaneously explain two extreme astrophysical puzzles.

Understanding dark matter halos and gravitational lenses

“The first is a halo of dense dark matter in a giant elliptical galaxy,” Yu said. “The halo is detected by observations of strong gravitational lenses, and its density is so high that it is extremely unlikely under the prevailing cold dark matter theory. Second, the density of dark matter halos in superdiffuse galaxies is extremely low. is extremely low and difficult to explain using cold dark matter theory.”

A dark matter halo is an invisible halo of matter that permeates and surrounds a galaxy or galaxy cluster. Gravitational lensing occurs when light traveling across space from a distant galaxy is bent around a massive object. The cold dark matter (CDM) paradigm/theory assumes that dark matter particles do not collide. As the name suggests, superdiffuse galaxies have extremely low luminosity and a dispersed distribution of stars and gas.

Hai-Bo Yu is a theoretical physicist at the University of California, Riverside, with expertise in the particle properties of dark matter.Credit: Samantha Tiu

Yu was also joined in the study by Ethan Nadler, a postdoctoral fellow at the Carnegie Observatory and the University of Southern California, and Danen Yang, a postdoctoral fellow at UCR.

To show that SIDM can explain two puzzles in astrophysics, the research team presents a theory of cosmic structure formation with strong dark matter self-interactions at relevant mass scales for strong lenticular halos and superdiffuse galaxies. We conducted our first high-resolution simulation.

“These self-interactions cause heat transfer within the halo and diversify the halo density in the central region of the galaxy,” Nadler said. “In other words, some halos have higher center densities and others have lower center densities compared to their CDM counterparts, the details of which depend on the evolutionary history of the Universe and the environment of the individual halo.”

Challenges to the CDM paradigm and future research

According to the research team, these two puzzles pose a formidable challenge to the standard CDM paradigm.

“CDM takes on the challenge of explaining these mysteries,” Yang said. “SIDM is probably a good candidate for reconciling two opposing extremes. There are no other explanations in the literature. We now know that dark matter may be more complex and active than we expected. There is an interesting possibility that there is.”

The study also demonstrates the ability to investigate dark matter through astrophysical observations using computer simulation tools of cosmic structure formation.

“We hope that our study will encourage further research in this promising research area,” Yu said. “This is a particularly timely development given the expected influx of data in the near future from observatories such as the James Webb Space Telescope and the upcoming Rubin Observatory.”

Since around 2009, the work of Yu and his collaborators has popularized SIDM in the particle physics and astrophysics communities.

References: Ethan O. Nadler, Danen Yang, and Haibo Yu, “Self-interacting dark matter solutions for the extreme diversity of low-mass halo properties,” November 30, 2023. Astrophysics Journal Letter.
DOI: 10.3847/2041-8213/ad0e09

This research was supported by the John Templeton Foundation and the U.S. Department of Energy.

Source: scitechdaily.com