Tag Archives: Photons

2025 Breakthrough: Physicists Discover Dark Photons, Transforming Our Understanding of Physics

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Dark photons in quantum physics

Dark Photons: A New Explanation for the Double-Slit Experiment

Russell Kightley/Science Photo Library

This year, a fundamental aspect of quantum theory faced scrutiny when researchers introduced a groundbreaking interpretation of an experiment exploring the nature of light.

Central to this research was the historic double-slit experiment, first conducted by physicist Thomas Young in 1801, which confirmed the wave-like behavior of light. Conventionally, particles and waves are considered distinct; however, in the quantum realm, they coexist, showcasing wave-particle duality.

For years, light stood as the quintessential example of this duality. Experimentation demonstrated that light can exhibit particle-like behavior as photons and wave-like characteristics, culminating in interference patterns reminiscent of Young’s findings. However, earlier in 2023, Celso Villas Boas and his team at Brazil’s Federal University of São Carlos proposed a novel interpretation of the double-slit experiment, exclusively utilizing photons and negating the wave aspect of optical duality.

After New Scientist covered their study, the team received significant interest from peers, with citations soaring. Villas-Boas shared, “I’ve received numerous invitations to present, including events in Japan, Spain, and Brazil,” emphasizing the widespread intrigue.

In the traditional double-slit experiment, an opaque barrier containing two narrow slits is positioned between a screen and a light source. Light travels through the slits to create a pattern of alternating bright and dark vertical stripes, known as classical interference, usually attributed to colliding light waves.

The researchers shifted away from this conventional explanation, examining the so-called dark state of photons—a unique quantum state that prevents interaction with other particles, hence not illuminating the screen. This perspective eliminates the necessity for light waves to clarify the observed dark stripes.

This reevaluation challenges a deeply ingrained view of light within quantum physics. Many educators expressed concern, with some remarking, “Your findings challenge the foundational concepts I’ve taught for years.” However, while some colleagues embraced the new perspective, others remained skeptically intrigued, following New Scientist‘s initial report.

Villas-Boas has been actively exploring implications surrounding the dark state of photons. His investigations revealed that thermal radiation, such as sunlight, can reside in a dark state, concealing a substantial portion of its energy due to a lack of interaction with other objects. Experimental validation could involve placing atoms in cavities where their interactions with light are meticulously examined, according to Villas-Boas.

His team’s reinterpretation of interference phenomena facilitates comprehension of previously perplexing occurrences, such as non-overlapping wave interactions. Moving beyond the wave model to incorporate distinct bright and dark photon states opens avenues for innovative applications. Villas-Boas envisions potential developments such as light-controlled switches and devices that selectively permit specific light types to pass.

In his view, all these explorations connect back to the essential principles of quantum physics, highlighting that engaging with quantum objects necessitates understanding their interactions with measurement devices—encompassing darkness itself. “This concept is intrinsic to quantum mechanics,” Villas-Boas asserts.

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Source: www.newscientist.com

The Interaction of Fast-Moving Electrons and Photons Drives X-Ray Emission in Blazar Jets

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A recent study utilized NASA’s IXPE (Imaging X-ray Polarized Explorer) to analyze a highly relativistic jet originating from the Blazar Bl Lacertae, a supermassive black hole surrounded by luminous discs.

This artist’s rendering illustrates the core area of Blazar Bl Lacertae, featuring an ultra-massive black hole surrounded by bright discs and Earth-directed jets. Image credit: NASA/Pablo Garcia.

Astrophysicists elucidated a highly relativistic jet, proposing two competing theories regarding an X-ray component made up of protons and electrons.

Each theory presents a distinct signature in the polarization characteristics of the X-ray light.

Polarized light signifies the average direction of the electromagnetic waves comprising light.

When X-rays in a black hole’s jets are highly polarized, it indicates production from protons that circulate within the magnetic field of the jet or protons interacting with the jet’s photons.

Conversely, low polarization in X-rays implies that the generation of X-rays occurs through electron-photon interactions.

The IXPE is the sole satellite capable of making such polarization measurements.

“This was one of the greatest mysteries involving supermassive black hole jets,” remarks Dr. Ivan Agdo, an astronomer at Astrophicidae Athtrophicidae and Andocia-CSIC.

“Thanks to numerous supporting ground telescopes, IXPE equipped us with the necessary tools to ultimately resolve this issue.”

Astronomers concluded that electrons are likely the source, through a process known as Compton scattering.

This phenomenon, also referred to as the Compton effect, occurs when photons lose or gain energy through interactions with charged particles (primarily electrons).

Within the jets of a supermassive black hole, electrons move at speeds approaching that of light.

IXPE enabled researchers to determine that, in Blazar jets, electrons possess enough energy to scatter infrared photons into the X-ray spectrum.

Bl Lacertae, one of the earliest discovered Blazars, was initially thought to be a kind of star in the Lacerta constellation.

IXPE monitored Bl Lacertae for seven days in November 2023, in conjunction with several ground-based telescopes also measuring optical and radio polarization.

Interestingly, during the X-ray polarization observations, Bl Lacertae’s light polarization peaked at 47.5%.

“This marks not only the most polarized BL Lacertae has been in the past 30 years, but indeed the highest ever recorded,” states Dr. Ioannis Riodakis, an astrophysicist at the Institute of Astrophysics.

Researchers noted that X-rays are significantly less polarized than optical light.

They were unable to detect strong polarized signals and ascertained that the X-rays could not exceed 7.6% polarization.

This finding confirms that electron interactions with photons via the Compton effect must account for the X-ray emissions.

“The fact that optical polarization is considerably higher than that of X-rays can only be explained by Compton scattering,” he added.

“IXPE has solved yet another mystery surrounding black holes,” claimed Dr. Enrico Costa, an astrophysicist associated with the planet spaziali of astituto to astituto to n diastrofísica.

“IXPE’s polarized X-ray capabilities have unraveled several long-standing mysteries, which is a significant achievement.

“In other instances, IXPE’s results challenged previously held beliefs, opening up new questions, but that’s the essence of science, and certainly IXPE excels in its scientific contributions.”

Survey results will be published in Astrophysics Journal Letter.

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Ivan Agd et al. 2025. The height of X-ray and X-ray polarization reveals Compton scattering of BL Lacertae jets. apjl in press; doi: 10.3847/2041-8213/ADC572

Source: www.sci.news

Physicists at CERN witness the creation of two tau leptons from two photons during a proton-proton collision

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According to physicists, CMS cooperation This is the first time this process has been observed in proton-proton collisions at CERN's Large Hadron Collider (LHC). This is also the most accurate measurement of tau's anomalous magnetic moment and provides a new way to constrain the existence of new physics.

We reproduced candidate events of the γγ →ττ process in proton-proton collisions measured by the CMS detector. Tau can decay into muons (red), charged pions (yellow), and neutrinos (not visible). Energy is stored in green in an electromagnetic calorimeter and cyan in a hadronic calorimeter. Image credit: CMS Collaboration.

of TauIt is a special particle of the lepton family, also called tauon.

In general, leptons, together with quarks, constitute the matter content of the Standard Model.

Tau was first discovered in the 1970s, and its associated neutrino (tau neutrino) was discovered by Fermilab's DONUT collaboration in 2000 to complete the tangible matter part.

However, tau has a very short lifetime and can remain stable for only 290*10 hours, making it quite difficult to study it accurately.-15 seconds.

Two other charged leptons, electrons and muons, are fairly well studied.

Much is also known about their magnetic moments and their associated anomalous magnetic moments.

The former can be understood as the strength and direction of a virtual bar magnet within the particle.

However, this measurable quantity requires correction at the quantum level resulting from the virtual particles pulling on the magnetic moment and deviates from the predicted value.

The quantum correction, called the anomalous magnetic moment, is about 0.1%.

If the theoretical and experimental results do not agree, this anomalous magnetic momentIopens the door to physics beyond the Standard Model.

The anomalous magnetic moment of the electron is one of the most accurately known quantities in particle physics and is in perfect agreement with models.

Its muon counterpart, on the other hand, is one of the most studied, and research is ongoing.

So far, theory and experiment are largely in agreement, but recent results raise tensions that require further investigation.

But for Tau, the race is still on. Its anomalous magnetic moment is particularly difficult to measure.τThis is because tau has a short lifespan.

The first attempt wasτ After the discovery of tau, there was an uncertainty 30 times higher than the size of the quantum correction.

Experimental efforts at CERN improved the constraints and reduced the uncertainty to 20 times the size of the quantum correction.

In collisions, physicists look for special processes. That is, two photons interact to produce two tau leptons (also called a ditau pair), which then decay into muons, electrons, or charged pions, and neutrinos.

So far, both ATLAS and CMS collaborations have observed this in ultraperipheral lead-to-lead collisions.

Now, CMS physicists report: first observation The same process occurs during proton-proton collisions.

These collisions provide greater sensitivity to physics over the standard model, as new physical effects increase with collision energy.

Taking advantage of the superior tracking capabilities of the CMS detector, the collaboration will isolate this particular process from other processes by selecting events that produce a tau with no other tracking within a distance of just 1 mm. I was able to separate it.

“This remarkable achievement in detecting proton-proton collisions in the super-periphery sets the stage for many breakthrough measurements of this kind from CMS experiments,” said Dr. Michael Pitt, a member of the CMS team. said.

This new method provided a new way to constrain tau's anomalous magnetic moments, and the CMS Collaboration quickly put it to the test.

Future driving data will likely improve the significance, but their new measurements impose the tightest constraints to date, with greater precision than ever before.

This reduces the prediction uncertainty to just three times the size of the quantum correction.

“We're really excited to finally be able to narrow down some of the fundamental properties of the elusive tau lepton,” said CMS team member Dr. Isaac Neutelings.

“This analysis introduces a new approach to investigating tau g-2 and revitalizes a measurement that has been stagnant for more than 20 years,” said CMS team member Dr. Xuelong Qin.

Source: www.sci.news

New Study Suggests Photons from Dwarf Galaxies Helped Reionize the Early Universe

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Reionization of the universe happened about 500 million to 900 million years after the Big Bang. This represents the transformation of neutral hydrogen into an ionized gas and marks the end of the “Dark Ages” in the history of the universe. Currently, astronomers using the NASA/ESA/CSA James Webb Space Telescope have obtained spectra of eight ultrafaint dwarf galaxies that existed less than a billion years after the Big Bang. Their observations could help settle long-standing scientific debates about the driving force of reionization and could also be essential to understanding the formation of the first galaxies.

Astronomers estimate that 50,000 near-infrared sources are represented in the Webb image of galaxy cluster Abel 2744. Image credits: NASA / ESA / CSA / I. Labbe, Swinburne Institute of Technology / R. Bezanson, University of Pittsburgh / A. Pagan, STScI.

There is still much we don’t understand about the period in the early history of the universe known as the Era of Reionization.

It was a time of darkness, without stars or galaxies, and filled with a thick fog of hydrogen gas, until the first stars ionized the surrounding gas and light began to pass through.

Astronomers have spent decades trying to identify sources that emit radiation powerful enough to gradually remove this hydrogen fog that blanketed the early universe.

“Our discovery reveals the important role played by ultrafaint galaxies in the evolution of the early universe,” said astronomer Dr. Irina Chemelinska from the Paris Institute of Astrophysics.

“They produce ionizing photons that convert neutral hydrogen into ionized plasma during the reionization of the universe.”

“This highlights the importance of understanding low-mass galaxies in shaping the history of the universe.”

“These cosmic power plants collectively emit more than enough energy to accomplish their work,” said Dr. Hakim Atek, also of the Paris Institute of Astrophysics.

“Despite their small size, these low-mass galaxies produce large amounts of energetic radiation, and their abundance during this period is so great that their collective impact alters the state of the entire universe can do.”

In the study, astronomers captured and analyzed the spectra of eight very faint galaxies magnified by the lensing star cluster Abel 2744.

They found that these galaxies emit large amounts of ultraviolet light, at levels four times higher than previously thought.

This means that most of the photons that reionized the Universe likely came from these dwarf galaxies.

“With the web, we have stepped into uncharted territory,” said Dr. Themiya Nanayakkara, an astronomer at Swinburne University of Technology.

“Our study reveals more provocative questions that must be answered in efforts to chart the evolutionary history of our beginnings.”

of result It was published in the magazine Nature.

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H. Atek other. 2024. Most of the photons that reionized the universe came from dwarf galaxies. Nature 626, 975-978; doi: 10.1038/s41586-024-07043-6

Source: www.sci.news