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Bazinga! Physicists crack a ‘Big Bang Theory’ problem that could help explain dark matter

A professor at the University of Cincinnati and his colleagues have figured out something two of America’s most famous fictional physicists couldn’t: how to theoretically produce subatomic particles called axions in fusion reactors.

Particle physicists Sheldon Cooper and Leonard Hofstadter, roommates in the sitcom “The Big Bang Theory,” worked on the problem in three episodes of Season 5, but couldn’t crack it.

Now UC physics Professor Jure Zupan and his theoretical physicist co-authors at the Fermi National Laboratory, MIT and Technion–Israel Institute of Technology think they have one solution in a study published in the Journal of High Energy Physics.

Physicists Propose First-Ever Experiment To Manipulate Gravitational Waves

When massive cosmic objects such as black holes merge or neutron stars crash into one another, they can produce gravitational waves. These ripples move through the universe at the speed of light and create extremely small changes in the structure of space-time. Their existence was first predicted by Albert Einstein, and scientists confirmed them experimentally for the first time in 2015.

Building on this discovery, Prof. Ralf Schützhold, a theoretical physicist at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), is proposing a bold new step.

Schützhold has developed a concept for an experiment that would go beyond detecting gravitational waves and instead allow researchers to influence them. The proposal, published in the journal Physical Review Letters, could also help clarify whether gravity follows quantum rules, a question that remains unresolved in modern physics.

Surprising optics breakthrough could transform our view of the Universe

FROSTI revolutionizes mirror control in gravitational-wave detectors, opening the door to a far deeper view of the cosmos. FROSTI is a new adaptive optics system that precisely corrects distortions in LIGO’s mirrors caused by extreme laser power. By using custom thermal patterns, it preserves mirror shape without introducing noise, allowing detectors to operate at higher sensitivities. This leap enables future observatories like Cosmic Explorer to see deeper into the cosmos. The technology lays the groundwork for vastly expanding gravitational-wave astronomy.

Gravitational-wave detectors may soon get a major performance boost, thanks to a new instrumentation advance led by physicist Jonathan Richardson of the University of California, Riverside. In a paper published in the journal Optica, Richardson and his colleagues describe FROSTI, a full-scale prototype that successfully controls laser wavefronts at extremely high power inside the Laser Interferometer Gravitational-Wave Observatory, or LIGO.

LIGO is an observatory that measures gravitational waves — tiny ripples in spacetime created by massive accelerating objects such as colliding black holes. It was the first facility to directly detect these waves, providing strong support for Einstein’s Theory of Relativity. Using two 4-km-long laser interferometers located in Washington and Louisiana, LIGO senses incredibly small disturbances, giving scientists a new way to study black holes, cosmology, and matter under extreme conditions.

What’s powering these mysterious, bright blue cosmic flashes? Astronomers find a clue

Among the more puzzling cosmic phenomena discovered over the past few decades are brief and very bright flashes of blue and ultraviolet light that gradually fade away, leaving behind faint X-ray and radio emissions. With slightly more than a dozen discovered so far, astronomers have debated whether they are produced by an unusual type of supernova or by interstellar gas falling into a black hole.

Analysis of the brightest such burst to date, discovered last year, shows that they’re neither.

Instead, a team of astronomers led by researchers from the University of California, Berkeley, concluded that these so-called luminous fast blue optical transients (LFBOTs) are caused by an extreme tidal disruption, where a black hole of up to 100 times the mass of our sun completely shreds its massive star companion within days.

Possible ‘superkilonova’ exploded not once but twice

When the most massive stars reach the ends of their lives, they blow up in spectacular supernova explosions, which seed the universe with heavy elements such as carbon and iron. Another type of explosion—the kilonova—occurs when a pair of dense dead stars, called neutron stars, smash together, forging even heavier elements such as gold and uranium. Such heavy elements are among the basic building blocks of stars and planets.

So far, only one kilonova has been unambiguously confirmed to date, a historic event known as GW170817, which took place in 2017. In that case, two neutron stars smashed together, sending ripples in space-time, known as gravitational waves, as well as light waves across the cosmos.

The cosmic blast was detected in gravitational waves by the National Science Foundation’s Laser Interferometer Gravitational-wave Observatory (LIGO) and its European partner, the Virgo gravitational-wave detector, and in light waves by dozens of ground-based and space telescopes around the world.

Strange, Record-Breaking Gamma-Ray Explosion Lasted 7 Hours and Defies Explanation

Data collected using multiple NSF NOIRLab facilities reveal a gamma-ray burst that lasted more than seven hours and originated in a massive, extremely dust-rich galaxy. Gamma-ray bursts (GRBs) rank among the most extreme explosions known in the Universe, surpassed only by the Big Bang itself. Mos

Laser light and the quantum nature of gravity: Proposed experiment could measure graviton energy exchange

When two black holes merge or two neutron stars collide, gravitational waves can be generated. They spread at the speed of light and cause tiny distortions in space-time. Albert Einstein predicted their existence, and the first direct experimental observation dates from 2015.

Now, Prof. Ralf Schützhold, theoretical physicist at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), is going one step further. He has conceived an experiment through which gravitational waves can not only be observed but even manipulated. Published in the journal Physical Review Letters, the idea could also deliver new insights into the hitherto only conjectured quantum nature of gravity.

“Gravity affects everything, including light,” says Schützhold. And this interaction also occurs when gravitational waves and light waves meet.

Dark matter search narrows as detector sets new limits and spots solar neutrinos

Australian researchers have played a central role in a landmark result from the LUX-ZEPLIN (LZ) experiment in South Dakota—the world’s most sensitive dark matter detector. Today, scientists working on the experiment report they have further narrowed constraints on proposed dark matter particles. And, for the first time, the experiment has detected elusive neutrinos produced deep inside the sun.

Scientists hypothesize that dark matter makes up about a quarter of the universe’s mass (or 85% of its matter) but have yet to detect exactly what makes up this strange phenomenon. The result announced today by the LZ experiment is one of the world’s most sensitive measurements in the hunt for dark matter. It has expanded its search for WIMPs (weakly interacting massive particles) down to masses approximately between that of three and nine times that of a proton, the positively charged particle in the nucleus of an atom.

Dr. Theresa Fruth, from the University of Sydney’s School of Physics, is one of only two Australian-based researchers in the 250-member international collaboration.

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