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Ancient Forces Behind Antarctica’s Gravitational Hole Uncovered by Earth Scientists

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A groundbreaking study by geoscientists at the University of Florida and the Paris Institute of Geophysics reveals the origin of Earth’s most severe gravity anomaly, known as the Antarctic Gravity Hole (or Antarctic Geoid Depression). This anomaly is attributed to millions of years of slowed underground rock flow.

Evolution of the Antarctic geoid cyclone. Image credit: P. Glišović & AM Forte, doi: 10.1038/s41598-025-28606-1.

According to Professor Alessandro Forte from the University of Florida, gaining a better understanding of how Earth’s interior influences gravity and sea levels can shed light on factors essential for the growth and stability of significant ice sheets.

“Variations in gravity due to differences in rock density beneath the surface, although small in absolute terms, can have a substantial impact on ocean levels,” he explained.

“In regions of reduced gravity, water tends to flow toward areas of higher gravity, causing sea levels to be relatively lower in those spots.”

“As a result of the Antarctic gravity hole, the sea level around Antarctica is significantly lower than it would typically be.”

In this research, Professor Forte and Dr. Petar Grišović from the Paris Institute of Geophysics have meticulously mapped out the Antarctic geoid cyclone, revealing its development throughout the Cenozoic Era, spanning from 66 million years ago to the present day.

The team utilized a global scientific initiative that integrates seismic data and advanced modeling techniques to reconstruct the 3D structure of Earth’s interior.

“It’s like performing a CT scan of the planet without the use of conventional X-rays,” Forte remarked.

“Earthquakes generate seismic waves, which act as the ‘light’ that reveals Earth’s inner structure.”

The researchers successfully created a global gravity map that aligns closely with satellite data, validating their underlying model.

The next challenge involved reversing the geophysical clock to examine how the Antarctic geoid cyclone has evolved over millions of years.

By employing physics-based reconstructions and sophisticated computer models, they retraced geological changes spanning 70 million years.

These historical analyses indicate that the Antarctic geoid cyclone began in a relatively weak state.

From approximately 50 to 30 million years ago, however, the gravity hole began to strengthen, coinciding with significant shifts in Antarctica’s climatic conditions, including the onset of a global ice age.

“We aim to test the causal relationship between this intensified gravity hole and the Antarctic ice sheet. Our new modeling will connect changes in gravity, sea levels, and continental elevation,” stated Professor Forte.

This research seeks to answer pivotal questions about the interactions between our climate and the processes occurring within Earth.

For more details, refer to the study published in December 2025 in the journal Scientific Reports.

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P. Grišović and A.M. Forte. 2025. Cenozoic evolution of Earth’s strongest geoid low reveals the dynamics of the Antarctic subsurface mantle. Scientific Reports 15, 45749; doi: 10.1038/s41598-025-28606-1

Source: www.sci.news

Gravitational Wave Signal Confirms Einstein’s Theory of Relativity

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Artist’s impression of black hole collision

Artist’s Impression of the Black Hole Collision Producing GW250114

A. Simonette/Sonoma State University, LIGO-Virgo-KAGRA Collaboration, University of Rhode Island

The groundbreaking collision of two black holes provides an exceptional opportunity for scientists to validate Einstein’s theory of general relativity, demonstrating the accuracy of physicists’ predictions once more.

In 2025, an international team of gravitational wave detectors, featuring state-of-the-art laser arrays, identified a significant distortion in space-time known as GW250114. This event is attributed to the merger of two black holes.

These advanced detectors—such as the US Laser Interferometer Gravitational-Wave Observatory (LIGO) and Italy’s Virgo detector—have achieved unprecedented sensitivity since LIGO’s inaugural detection in 2016. Consequently, GW250114 offers the clearest and most detailed data on gravitational wave phenomena to date, serving as a unique testing ground for well-established physical theories.

Recently, researchers applied data from GW250114 to evaluate Stephen Hawking’s theorem, posited over half a century ago. This theorem claims that the event horizon of a merging black hole cannot be smaller than the total mass of its progenitor black holes. The findings confirmed Hawking’s prediction with near certainty.

Keefe Mittman and his team at Cornell University took this analysis a step further by assessing whether black hole mergers comply with Albert Einstein’s theoretical framework.

Einstein’s equations articulate how massive objects navigate space-time. By manipulating and resolving these equations for the merging black holes, researchers can visualize the dynamics: the black holes spiral together, accelerate, collide, release substantial energy, and subsequently resonate at distinct frequencies—akin to a bell chiming after a strike.

These frequencies, referred to as ringdown modes, were relatively faint in prior gravitational wave events, obscuring the complex structures foreseen by Einstein. However, GW250114 generated enough amplitude to effectively validate the predicted oscillation patterns. Mittmann and his colleagues utilized simulations based on Einstein’s equations to estimate the intensity and frequencies of the black hole’s oscillations. The actual measurements closely aligned with these predictions.

“The amplitudes of the data we measured align remarkably well with the predictions of numerical relativity,” Mittmann confirms. “Einstein’s equations may be complex to solve, yet the correlations observed at the detector validate general relativity.”

“The conclusion is clear: Einstein’s predictions still hold true,” states Laura Nuttall from the University of Portsmouth, UK. “All observations correspond to Einstein’s assertions regarding gravity.”

Despite the impressive amplitude of GW250114, the frequencies remain faint enough that Mittmann’s team couldn’t dismiss a variance from Einstein’s predictions of less than 10 percent. This limitation primarily results from current detector sensitivities and is likely to lessen as gravitational wave detection technology evolves. Any deviations from Einstein’s theory would manifest as persistent discrepancies.

“As we catalog more events or observe larger singular events, the measurement error margins can approach zero—or diverge,” Mittmann notes. “A divergence would be considerably more intriguing.”

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Updated on February 11, 2026

Amended information regarding the characteristics of ringdown modes in prior gravitational wave events.

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Source: www.newscientist.com

Gravitational Waves Confirm Stephen Hawking’s Black Hole Theory

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Illustration of two black holes merging and emitting gravitational waves throughout the universe

Maggie Chiang from the Simons Foundation

Stephen Hawking’s theorem, established over 50 years ago, has aided astronomers in detecting waves produced by extraordinarily powerful collisions as they traverse Earth at light speed, shedding light on the merging of black holes thanks to significant advancements in gravitational wave astronomy.

In 1971, Hawking introduced the Black Hole Area theorem, which posits that when two black holes combine, the resultant event horizon cannot be smaller than the combined size of the original black holes. This theorem aligns with the second law of thermodynamics, which asserts that the entropy of a system cannot decrease.

The merging of black holes warps the structure of the universe, generating tiny ripples in space-time known as gravitational waves that move through the cosmos at the speed of light. Five gravitational wave observatories on Earth search for waves that are 10,000 times smaller than an atom. These include two detectors in the US—LIGO, a laser interferometer, alongside Italy’s Virgo, Japan’s Kagura, and Germany’s GEO600.

The recent event, named GW250114, mirrors the event that first detected gravitational waves in 2015.

Now, the upgraded LIGO detector is three times more sensitive than it was in 2015, enabling the capture of waves from collisions with remarkable detail. This has allowed scientists to confirm Hawking’s theorem, proving that the size of the event horizon actually increases following a merger.

When black holes collide, they generate gravitational waves with overtones akin to the sound of a ringing bell, as noted by Laura Nuttall, a member of the LVK team at the University of Portsmouth, UK. Previously, these overtones were too rapid to be detected clearly enough to assess the area of the event horizon before and after a merger, a crucial requirement to test Hawking’s theory. The initial 2021 study supporting the theory confirmed it at a 95% confidence level, but the latest findings suggest an impressive 99.999% confidence.

Over the past ten years, scientists have witnessed approximately 300 black hole collisions while observing gravitational waves. However, none have been as strong as GW250114, which was twice as powerful as any previously detected gravitational wave.

“What we are discovering in our data has tremendous implications for understanding basic physics,” remarked a researcher. “We’re eager for nature to provide us with further astonishing revelations.”

Only LIGO was operational when GW250114’s waves reached Earth; other detectors in the LVK collaboration were not active. This did not affect the validation of Hawking’s theory but limited researchers’ ability to pinpoint the waves’ origins more precisely.

Future upgrades to LIGO and upcoming observatories are anticipated to enhance sensitivity, offering deeper insights into black hole physics, according to Ian Harry, also from the University of Portsmouth and part of the LVK team. “We may miss some events, but we will certainly capture similar phenomena again,” Harry expressed. “Perhaps with our next set of upgrades in 2028, we might witness something of this magnitude and gain deeper insights.”

These findings pave the way for future research into quantum gravity, a field where physicists aim to reconcile general relativity with quantum mechanics. Nuttall stated that the latest results indicate that both theories remain compatible, although inconsistencies are expected in future observations.

“At some point, discrepancies are likely to emerge, especially when close signals appear noisy as the detector’s sensitivity improves,” Nuttall explained.

Moreover, the recent data from LVK enabled scientists to confirm equations proposed by mathematician Leakir in the 1960s, which suggested that black holes could be described by two key metrics: mass and spin. Essentially, two black holes with identical mass and spin are mathematically indistinguishable. Observations from GW250114 have verified this assertion.

Physical Review Letters
doi: 10.1103/kw5g-d732

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Astrophysicists Identify Gravitational Waves from the Largest Black Hole Mergers Recorded to Date

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The twin detectors of the NSF’s Laser Interferometer Gravitational-Wave Observatory (LIGO) have made a groundbreaking discovery by detecting the highest composite mass recorded to date and the merger of two black holes. This event, identified as GW231123 and discovered on November 23, 2023, produced a final black hole with a mass over 225 times that of the Sun.

GW231123 An infographic detailing the merger of black holes. Image credits: Simona J. Miller/Caltech.

LIGO made history in 2015 with the first direct detection of gravitational waves, the ripples in spacetime.

In that instance, the waves were generated by the merger of black holes, culminating in a black hole with a mass 62 times that of our Sun.

The signal was simultaneously detected by LIGO’s twin detectors located in Livingston, Louisiana, and Hanford, Washington.

Since then, the LIGO team has collaborated with partners from Italy’s Virgo detectors and Japan’s KAGRA to create the LVK collaboration.

These detectors have collectively observed over 200 black hole mergers during their fourth observational run since starting in 2015.

Previously, the largest black hole merger recorded was in 2021 during the event GW190521, which had a total mass of 140 times that of the Sun.

During the GW231123 event, a black hole with a mass of 225 was formed by merging two black holes, one approximately 100 times and the other 140 times the mass of the Sun.

This discovery places it in a rare category known as intermediate mass black holes, which are heavier than those resulting from star collapses but significantly lighter than the supermassive black holes found at the centers of galaxies.

In addition to their substantial mass, these merged black holes exhibited rapid rotation.

“This is the largest black hole binary we’ve observed in gravitational waves and poses a significant challenge to our understanding of black hole formation,” stated Dr. Mark Hannam, an astrophysicist at Cardiff University and a member of the LVK collaboration.

“The existence of such a large black hole defies standard stellar evolution models.”

“One potential explanation is that the two black holes in this binary could have formed from the merger of smaller black holes.”

“This observation highlights how gravitational waves uniquely uncover the fundamental and exotic properties of black holes throughout the universe,” remarked Dr. Dave Reitze, executive director of LIGO at Caltech.

Researchers announced this week the discovery of GW231123, which will be discussed at the 24th International Conference on General Relativity and Gravity (GR24) and the 16th Edoardo Amaldi Meeting on Gravitational Waves, held jointly at the Gr-Amaldi Meeting in Glasgow, Scotland.

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LIGO-Virgo-KAGRA Collaboration. GW231123: The largest black hole binary detected by gravitational waves. Gr-Amaldi 2025

Source: www.sci.news

New research suggests that gravitational waves are responsible for the mid-ambient atmosphere on Mars

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According to a new study by planetary researchers at Tokyo Planet University, atmospheric gravity waves play an important role in driving airflows, particularly at altitudes, at latitudes.

This image from the Emirates Mars Mission shows Mars and its thin atmosphere. Image credit: UAESA/MBRSC/HOPE MARS MISSION/EXI/ANDREALUCK.

“On Earth, the large atmospheric waves caused by the rotation of a planet known as the Rossby waves are the main effect on the way stratospheric air circulates, or the lower part of the medium atmosphere.”

“However, our research shows that on Mars, gravitational waves have the dominant effect in the mid-atmosphere and at high latitudes.”

“Rossby's waves are large atmospheric or resolved waves, while gravitational waves are unresolved waves, meaning that they must be estimated using finer, more indirect means to be measured or modeled.”

“Don't confuse it with gravitational waves from the body of a large star. Gravitational waves are atmospheric phenomena when packets of air rise and fall due to buoyancy fluctuations. Their oscillating movements cause gravitational waves.”

Due to their small-scale nature and limitations of observational data, planetary researchers previously discovered that it is difficult to quantify their importance in the Martian atmosphere.

Therefore, Professor Sato and her colleagues turned to the Ensemble Mars Atmosphere Reanalysis System (EMARS) dataset generated by various space-based observations over the years to analyze seasonal variation.

“We found something interesting. Gravitational waves promote the rapid vertical movement of angular momentum, which has a major impact on the meridian or north-north in the mid-atmospheric circulation on Mars,” said Anzu Asumi, a graduate student at Tokyo University.

“It's interesting because it's more like the behavior seen in the Earth's mesosphere, not in our stratosphere.”

“This suggests that the effects of these waves may need to be better incorporated to improve existing Mars atmospheric circulation models, and could improve future climate and weather simulations.”

The team is currently planning to investigate the effects of Mars sandstorms on atmospheric circulation.

“So far, our analysis has focused on a year without large sandstorms,” ​​Professor Sato said.

“However, I think these storms could dramatically change the state of the atmosphere and strengthen the role of gravitational waves in circulation.”

“In our research, there is a basis for predicting Mars weather, which is essential to guarantee the success of future Mars missions.”

study It will be displayed in Journal of Journal Geophysics: Planets.

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Anzu Asumi et al. Climatology of the residual average circulation of the Martian atmosphere and the contribution of solutions and unresolved waves based on reanalysis datasets. Journal of Journal Geophysics: PlanetsPublished online on March 6th, 2025. doi:10.1029/2023je008137

Source: www.sci.news

LIGO hunts for gravitational waves produced by mountains on neutron stars

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While the solar system’s moons such as Europa and Enceladus have thin crusts over deep oceans, Mercury has a thin crust over a large metallic core. Thin sheets are generally likely to wrinkle. Europa has linear features, Enceladus has “tiger stripes” and Mercury has foliated cliffs. Neutron stars may have similar characteristics. These neutron star mountains can generate detectable oscillations in space and time known as gravitational waves, according to a new study.

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

Neutron stars are a trillion times denser than lead, and their surface features are largely unknown.

Nuclear theorists investigated the mountain-building mechanisms active on the moons and planets of the solar system.

Some of these mechanisms suggest that neutron stars likely have mountains.

A mountain in a neutron star would be much more massive than any mountain on Earth. They are so huge that the gravitational pull from these mountains alone can generate gravitational waves.

of Laser interferometer Gravitational wave observatory (LIGO) is currently looking for these signals.

“These waves are so weak that they require highly detailed and sensitive techniques carefully tuned to the expected frequencies and other signal characteristics,” said nuclear astrophysicist Jorge Morales and professor Charles Horowitz at Indiana University. It can only be discovered through search.”

“The first detection of continuous gravitational waves opens a new window on the universe and will provide unique information about neutron stars, the densest objects after black holes.”

“These signals may also provide sensitive tests of fundamental laws of nature.”

The authors investigated the similarities between neutron star mountains and surface features of solar system objects.

“While both neutron stars and certain moons, such as Jupiter’s moon Europa and Saturn’s moon Enceladus, have a thin crust over a deep ocean, Mercury has a thin crust over a large metallic core. The thin sheet Wrinkles are universally possible,” they said.

“Europa has linear features, Enceladus has tiger-like stripes, and Mercury has curved, step-like structures.”

“Mountained neutron stars may have similar types of surface features that can be discovered by observing continuous gravitational wave signals.”

“Earth’s innermost core is anisotropic, and its shear modulus is direction-dependent.”

“If the material in the neutron star’s crust is also anisotropic, a mountain-like deformation will occur, and its height will increase as the star rotates faster.”

“Such surface features could explain the maximum spin observed in neutron stars and the minimum possible deformation of radio-emitting neutron stars known as millisecond pulsars.”

team’s paper Published in a magazine Physical Review D.

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JA Morales and CJ Horowitz. 2024. The anisotropic neutron star crust, the mountains of the solar system, and gravitational waves. Physics. Rev.D 110, 044016; doi: 10.1103/PhysRevD.110.044016

Source: www.sci.news

Astronomers achieve unprecedented level of detail in creating gravitational wave background map

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Astronomers using the MeerKAT Pulsar Timing Array, an international experiment using South Africa’s MeerKAT radio telescope, have discovered further evidence of gravitational wave signals originating from supermassive black hole mergers.

miles others. Created the most detailed map of gravitational waves throughout the universe to date. Image credit: Carl Knox / OzGrav / Swinburne University of Technology / South African Radio Astronomical Observatory.

“Our research opens up new avenues for understanding the universe we live in,” said astronomer Dr Matt Miles from the ARC Gravitational Wave Discovery Center (OzGRav) and Swinburne University of Technology. .

“By studying the background, we can listen to the echoes of cosmic events over billions of years. It reveals how galaxies and the universe itself have evolved over time.”

The MeerKAT Pulsar Timing Array observes and times pulsars (fast-spinning neutron stars) with nanosecond precision.

Pulsars act as natural clocks, and their steady pulses allow scientists to detect minute changes caused by passing gravitational waves.

This galaxy-scale detector provides the opportunity to map gravitational waves across the sky, revealing patterns and intensities that defy previous assumptions.

“The gravitational wave background is often thought to be uniformly distributed across the sky,” says Rowena Nathan, an astronomer at Ozgrab University and Monash University.

“The galaxy-sized telescope formed by the MeerKAT pulsar timing array allows us to map the structure of this signal with unprecedented precision, potentially revealing insights into its source.”

Astronomers have found further evidence of gravitational wave signals originating from merging supermassive black holes, capturing a signal more powerful than a similar global experiment in just one-third of the time.

“What we’re seeing suggests a much more dynamic and active Universe than we expected,” Dr. Miles said.

“We know that supermassive black holes are merging off Earth, but now we’re starting to know where they are and how many there are.”

Researchers used pulsar timing arrays to improve existing methods to build highly detailed gravitational wave maps.

This map revealed an interesting anomaly: an unexpected hotspot in the signal, suggesting a possible directional bias.

“The presence of a hotspot could point to a distinct source of gravitational waves, such as a pair of black holes billions of times more massive than the sun,” Nathan said.

“Looking at the arrangement and pattern of gravitational waves tells us how our universe exists today and contains signals from around the time of the Big Bang.”

“While there is still more work to be done to determine the significance of the hotspots we discovered, this is an exciting step forward for our field.”

“These discoveries raise exciting questions about the formation of supermassive black holes and the early history of the universe.”

“Further monitoring by the MeerKAT array could improve these gravitational wave maps and reveal new cosmic phenomena.”

“The research also has broader implications, with data that could help international scientists explore the origin and evolution of supermassive black holes, the formation of galactic structures, and even hints at early cosmic events. provided.”

The results were published in three papers. Royal Astronomical Society Monthly Notices.

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Matthew Miles others. 2024. MeerKAT Pulsar Timing Array: 4.5 Years of Data Release and Noise and Stochastic Signals in the Millisecond Pulsar Population. MNRASin press. doi: 10.1093/mnras/stae2572

Matthew Miles others. 2024. MeerKAT Pulsar Timing Array: The first search for gravitational waves with the MeerKAT radio telescope. MNRASin press. doi: 10.1093/mnras/stae2571

Kathryn Grandthal others. 2024. MeerKAT Pulsar Timing Array: Map of the gravitational wave sky with 4.5 years of data released. MNRASin press. doi: 10.1093/mnras/stae2573

Source: www.sci.news

Theoretical astrophysicists debate the generation of gravitational waves during warp drive collapse

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The basic idea of ​​a warp drive is that rather than directly exceeding the speed of light in a local frame of reference, a “warp bubble” contracts space-time in front of it and expands it behind it, allowing travel over distances faster than the speed of light as measured by a distant observer.

Craft othersWe propose a formalism for the dynamical study of warp drive spacetime and generate the first fully consistent numerical relativistic waveforms for the collapse of a warp drive bubble.

Although warp drive has its origins in science fiction novels, according to Miguel Alcubierre, an astrophysicist at the University of Wales, warp drive is explained in detail in the general theory of relativity. Be the first to propose A space-time metric that supports faster-than-light travel.

Real-world implementation has many practical barriers, such as the need for a special type of material that has negative energy, but computationally, given an equation of state describing the material, it is possible to simulate changes over time.

In a new study, theoretical astrophysicists investigated the signatures that could result from a “containment failure” of a warp drive.

“Warp drives are purely theoretical, but they are clearly described in Einstein's general theory of relativity, and numerical simulations allow us to explore the effects of warp drives on space-time in the form of gravitational waves,” said Dr Katie Clough, researcher at Queen Mary, University of London.

“The results are fascinating: the warp drive collapse produces a unique gravitational wave burst — a ripple in space-time that can be detected by gravitational wave detectors that typically target merging black holes and neutron stars.”

“Unlike chirp signals from merging objects, this signal is a short, high-frequency burst that would be undetectable by current detectors.”

“But there may be higher frequency devices in the future, and although the money hasn't been put into those devices yet, the technology exists to build them.”

“This raises the possibility that we could use these signals to look for evidence of warp drive technology, even if we can't build it ourselves.”

“In our study, the initial shape of spacetime is the warp bubble described by Alcubierre,” said Dr Sebastian Kahn, a researcher at Cardiff University.

“Although we demonstrate that an observable signal could, in principle, be found by future detectors, the speculative nature of this work is not sufficient to drive instrument development.”

The authors also take a detailed look at the energy dynamics of a collapsing warp drive.

In this process, waves of negative energy matter are released, followed by alternating waves of positive and negative energy.

This complex dance results in a net increase in energy throughout the system and, in principle, could provide another signature of collapse if the emission waves interacted with ordinary matter.

“This is a reminder that theoretical ideas can inspire us to explore the universe in new ways,” Dr Clough said.

“I'm skeptical that we'll see anything, but I think it'll be interesting enough to be worth a look.”

“For me, the most important aspect of this work is the novelty of accurately modelling the dynamics of negative energy space-time and the possibility that the technique can be extended to physical situations that could help us better understand the evolution and origin of the universe or processes at the centre of black holes,” said Professor Tim Dietrich of the University of Potsdam.

“While warp speed may still be a long way away, this research is already pushing the boundaries of our understanding of extra-dimensional space-time and gravitational waves.”

“We're going to try different models of warp drive to see how that changes the signal.”

Team paper Published online Open Astrophysics Journal.

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Katie Clough othersThe year is 2024. A phenomenon no one has seen before: gravitational waves caused by warp drive collapse. Open Astrophysics Journal 7;doi:10.33232/001c.121868

Source: www.sci.news

Graviton: An Insight into a Particle with Gravitational Behavior

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Have you found any traces of gravitons?

zf L/Getty Images

For decades, physicists have been searching for gravitons, the hypothetical particles thought to carry gravity. Although they had never been detected in space, particles like gravitons have now been observed in semiconductors. Using these to understand the behavior of gravitons could help unify general relativity and quantum mechanics, which have long been at odds.

“This is a needle in a haystack. [finding]. And the paper that started all this goes back to 1993. ” lauren pfeiffer at Princeton University. He wrote the paper with several colleagues. Aaron Pinchukdied in 2022 before finding any hint of the elusive particle.

Pinchuk's students and collaborators, including Pfeiffer, have completed the experiment they began discussing 30 years ago. They focused on electrons within a flat piece of the semiconductor gallium arsenide, which they placed in a powerful refrigerator and exposed to a strong magnetic field. Under these conditions, quantum effects cause electrons to behave in strange ways. The electrons interact strongly with each other, forming an unusual incompressible liquid.

Although this liquid is not gentle, it is characterized by collective motion in which all the electrons move in unison, which can lead to particle-like excitations. To investigate these excitations, the team illuminated the semiconductor with a carefully tuned laser and analyzed the light scattered from the semiconductor.

This revealed that the excitation contains a type of quantum spin that had previously been theorized to exist only in gravitons. This isn't a graviton itself, but it's the closest thing we've ever seen.

Liu Ziyu The professor at Columbia University in New York who worked on the experiment said he and his colleagues knew that graviton-like excitations could exist in semiconductors, but they needed to make the experiment precise enough to detect it. He said it took many years. “From a theoretical side, the story was kind of complete, but the experiments weren't really convincing,” he says.

This experiment is not a true analog of space-time. Electrons are confined in flat, two-dimensional space and move more slowly than objects governed by the theory of relativity.

But he says it is “hugely important” and bridges various previously underappreciated areas of physics, such as materials physics and the theory of gravity. Kun Yan from Florida State University was not involved in this study.

but, Zlatko Papik Researchers at the University of Leeds in the UK cautioned against equating the new discovery with the detection of gravitons in space. He said the two are equivalent enough for electronic systems like the one in the new experiment to serve as a testing ground for theories of quantum gravity, but they are not equivalent for all quantum phenomena that occur in space-time on a cosmic scale. It says no.

This connection between particle-like excitations and theoretical gravitons also yields new ideas about exotic electronic states, team members say. de Linjie At Nanjing University, China.

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Source: www.newscientist.com

Physicists are delving into quantum gravity using the concept of gravitational rainbows

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The fans roar to life, pumping air upwards at 260 kilometers per hour. Wearing a baggy blue jumpsuit, red helmet, and plastic goggles, claudia de rum When you step into the glass room… Whoosh! Suddenly, she was suspended in the air, her wide grin on her face excited by her simulated experience of free fall.

I persuaded de Lamme, a theoretical physicist at Imperial College London, to go indoor skydiving with me at iFLY London. It seemed appropriate, given that much of her life has been dedicated to exploring the limits and true nature of gravity. At least on this occasion, jumping out of the plane wasn't an option for her.

As she explains in her new book, the beauty of falling, de Rum trained to be a pilot and then an astronaut, but medical problems ruined his chance for the ultimate escape from gravity. But as a theorist, she continued to delve deeper into this most familiar and mysterious force, making her mark by asking her fundamental question: “What is the weight of gravity?” Ta.

That means she is a graviton, a hypothetical particle that is thought to carry this force. If it had mass, as de Rum suspects, that would open a new window on gravity. Among other things, we may finally discover a “gravitational rainbow” that betrays the existence of gravitons. Along with gravitons, it will also become possible to provide a quantum description of gravity, which has been sought for many years.

When De Rum is suspended in the air, she makes it look easy. She will ascend soon…

Source: www.newscientist.com

The gravitational force of Mars could potentially disturb Earth’s oceans

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The planets are doing a gravitational dance around the sun

Shutterstock/Johan Swanepoel

Mars’ gravitational pull could be strong enough to shake up Earth’s oceans and shift sediment as part of a 2.4 million-year climate cycle, researchers claim.

It has long been recognized that wobbles in Earth’s orbit around the sun affect Earth’s climate, and these Milankovitch cycles operate at intervals measured in thousands of years. Now, Adriana Dutkiewicz and his colleagues at the University of Sydney say they have discovered a 2.4-million-year “great cycle” that is driven by Mars and has dramatically affected the flow of Earth’s oceans for at least 40 million years. It is believed that it has been given.

Evidence for this cycle comes from approximately 300 deep-sea drill cores, revealing unexpected fluctuations in marine sediment deposition. During periods of stable ocean currents, oceanographers expect sediment to be deposited in stable layers, but when abnormal currents or eddies occur, sediment can be deposited elsewhere.

The researchers say the gaps or hiatus in the sediment record coincide with the period when Mars’ gravity exerts its greatest force on Earth, exerting subtle effects on the stability of Earth’s orbit. This changes solar radiation levels and climate, manifesting as stronger currents and eddies in the ocean.

team members Dietmar MullerResearchers, also from the University of Sydney, acknowledged that the great distance between Earth and Mars makes it unlikely that there is any significant gravitational force at work. “But there is so much feedback that even the slightest change can be amplified,” he says. “Mars’ influence on Earth’s climate is similar to the butterfly effect.”

benjamin mills Researchers from the University of Leeds in the UK say the drill core provides further evidence of the existence of “megacycles” in global environmental change.

“Many of us have seen these multimillion-year cycles in various geological, geochemical, and biological records, such as during the famous Cambrian explosion of animal life,” he said. says. “This paper helps solidify these ideas as an important part of environmental change.”

but matthew england A professor at the University of New South Wales in Sydney welcomed the study and said he believed it would improve our understanding of climate cycles on a geological scale, but said he was not convinced by the paper’s conclusions.

“I’m skeptical about the Mars connection, given that Mars’ gravitational pull on Earth is very weak, only about a millionth of the Sun’s gravitational pull,” he says. “Even Jupiter has a stronger gravitational field than Earth.”

The UK also points out that even if there is an impact from Mars, it will be negligible compared to human-induced climate change. “By comparison, greenhouse gas forcing is like a sledgehammer and has no effect on our current climate, where melting ice sheets are reducing ocean circulation.”

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Source: www.newscientist.com

Physicists conclude the shape factor of a proton’s Grunick gravitational force

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Protons are one of the main building blocks of all visible matter in the universe. Its unique properties include charge, mass, and spin. These properties emerge from the complex dynamics of its basic building blocks, quarks and gluons, explained by the theory of quantum chromodynamics. The charge and spin of protons shared between quarks has been previously studied using electron scattering. One example is the high-precision measurement of the charge radius of protons. In contrast, little is known about the internal mass density of protons, which is dominated by the energy carried by gluons. In a new study, a team of physicists led by Argonne National Laboratory used a small colored dipole to probe the gravitational density of gluons through threshold photogeneration of J/ψ (J/Psi) particles.

Proton valence quarks (blue, red, green), quark and antiquark pairs, and gluons (springs). Scalar gluon activity (pink) extends beyond the charge radius (orange) surrounding the gluon energy core (yellow). Image credit: Argonne National Laboratory.

For many years, nuclear physicists have determined the size of protons by precisely measuring their charge response. This is a result of the proton's charged constituent quarks.

However, determining the size of matter by the size of its protons is a more difficult task. This is because part of the proton's mass is driven by the elusive neutral gluon, rather than by the mass or motion of charged quarks. These gluons combine themselves with quarks within the proton.

The new discovery provides a view of this mass region produced by gluon interactions.

This measurement not only reveals the mass radius resulting from the strong force, but also its confinement effect on quarks that extend far beyond the proton's charge radius.

“A key detail of the proton's structure is its size,” said lead author Dr. Zein Eddin Meziani, a physicist at Argonne National Laboratory, and his colleagues.

“The most commonly used measure of a proton's size is its charge radius, which uses electrons to measure the spherical size of the proton's charge.”

The new measurements come from the J/Ψ -007 experiment at the Thomas Jefferson National Accelerator Facility.

This differs in that a small colored dipole ( ) was used to reveal the sphere size and position of the gluon mass and its range of influence on the gluon within the proton.

In the experiment, physicists used a high-energy beam of electrons to create J/Ψ particles from protons. The J/Ψ particle provides information about the distribution of gluons inside the proton.

Experimenters inserted these measurements into a theoretical model and analyzed them.

As a result, the mass radius of the gluon inside the proton was determined.

Furthermore, the area of ​​influence of a strong force called a confinement scalar cloud, which also affects proton quarks, was also shown.

“This study paves the way for a deeper understanding of the prominent role of gluons in imparting gravitational mass to visible matter,” the authors concluded.

Their paper It was published in the magazine Nature.

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B. Duran other. 2023. Determination of the Grunick gravitational shape factor of protons. Nature 615, 813-816; doi: 10.1038/s41586-023-05730-4

Source: www.sci.news

Thermal secrets uncovered in neutron star mergers through gravitational waves

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by US Department of Energy
December 14, 2023

Scientists used supercomputer simulations to study gravitational waves produced by neutron star mergers and found a correlation between residual temperature and gravitational wave frequency. These findings are important for future gravitational wave detectors that distinguish models of hot nuclear material. Credit: SciTechDaily.com

Binary simulation neutron star This merger suggests that future detectors will distinguish between different models of hot nuclear material.

Researchers used supercomputer simulations to investigate the effects of neutron star mergers gravitational waves, found a significant relationship with debris temperature. This research will aid future advances in the detection and understanding of hot nuclear materials.

Exploring neutron star mergers and gravitational waves

When two neutron stars orbit each other, they emit ripples into spacetime called gravitational waves. These ripples drain energy from the orbit until the two stars eventually collide and combine into one object. Scientists used supercomputer simulations to investigate how the behavior of different models of nuclear material affects the gravitational waves released after these mergers. They found a strong correlation between the temperature of the debris and the frequency of these gravitational waves. Next generation detectors will be able to distinguish these models from each other.

Plot comparing density (right) and temperature (left) for two different simulations (top and bottom) of a neutron star merger, viewed from above, approximately 5 ms after the merger.Credit: Jacob Fields, Pennsylvania State University

Neutron Star: Institute for Nuclear Materials

Scientists use neutron stars as laboratories for nuclear materials under conditions that would be impossible to explore on Earth. They will use current gravitational wave detectors to observe neutron star mergers and learn how cold, ultra-dense matter behaves. However, these detectors cannot measure the signal after the stars have merged. This signal contains information about hot nuclear material. Future detectors will be even more sensitive to these signals. Because different models can also be distinguished from each other, the findings suggest that future detectors could help scientists create better models of hot nuclear material.

Detailed analysis of neutron star mergers

The study investigated neutron star mergers using THC_M1, a computer code that simulates neutron star mergers and accounts for the bending of spacetime due to the star’s strong gravitational field and neutrino processes in dense matter. . The researchers tested the effect of heat on mergers by varying the specific heat capacity of the equation of state, which measures the amount of energy required to raise the temperature of neutron star material by one degree Celsius. To ensure the robustness of their results, the researchers ran their simulations at two resolutions. They repeated the high-resolution run using a more approximate neutrino processing.

References:

“Thermal effects in binary neutron star mergers” by Jacob Fields, Aviral Prakash, Matteo Breschi, David Radice, Sebastiano Bernuzzi, and Andre da Silva Schneider, July 31, 2023. of Astrophysics Journal Letter.
DOI: 10.3847/2041-8213/ace5b2

“Identification of nuclear effects in neutrino-carbon interactions in low 3 momentum transfer” until February 17, 2016 physical review letter.
DOI: 10.1103/PhysRevLett.116.071802

Funding: This research was primarily funded by the Department of Energy, Office of Science, Nuclear Physics Program. Additional funding was provided by the National Science Foundation and the European Union.

This research used computational resources available through the National Energy Research Scientific Computing Center, the Pittsburgh Supercomputing Center, and the Pennsylvania State University Computing and Data Science Institute.

Source: scitechdaily.com