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The complete evolution of spin glass from order to chaos

How come our universe is full of disorder, when all elementary particles appear to follow strictly ordered laws of physics? And are there organizing principles behind disorder and apparent chaos?

One avenue of studying these fundamental questions is through an assembly of spins: the quantum property that makes electrons behave like tiny bar magnets, with a preferred orientation of either up or down. Neighboring spins align either in parallel (up-up) or antiparallel (up-down-up-down), as in ferromagnets and antiferromagnets, respectively. This simple ruleset makes spin systems very attractive for studying the emergence of order.

However, while the theory of spin is well-established, creating the material conditions for observing spin disorder has proven notoriously elusive. While physicists have been able to create exotic materials that exhibit spin disorder, tracing the evolution from order to disorder within materials has been challenged by the lack of a clean starting point.

NASA’s Fermi glimpses power source of supercharged supernovae

LSU researchers helped uncover what may be the first clear detection of gamma rays from a superluminous supernova, using data from NASA’s Fermi Gamma-ray Space Telescope—a breakthrough that offers new insight into the powerful magnetars believed to drive some of the universe’s brightest stellar explosions.

An international team studying data from NASA’s Fermi Gamma-ray Space Telescope concludes the mission detected a rare, unusually luminous supernova. The researchers say it likely received its power-up from a supermagnetized neutron star born in the stellar collapse that triggered the explosion.

The Fermi mission is part of NASA’s fleet of observatories monitoring the changing cosmos to help humanity better understand how the universe works.

The quantum key to seeing through chaos

Researchers from the Institut des NanoSciences de Paris, the Kastler Brossel Laboratory and the University of Glasgow have developed an innovative method that renders a scattering medium transparent solely for information carried by entangled photon pairs, while the same medium remains completely opaque to classical light.

Their works are published in the journals Optica (optimization) and Nature Physics (selective image transmission).

Faithfully transmitting spatial information, such as the image of an object, is a major challenge in modern optics. However, this task becomes complex as soon as light travels through disordered media, such as biological tissues, atmospheric turbulence, or multimode optical fibers. In these environments, scattering scrambles the information, making the final image completely unreadable.

Quantum sensors use atoms, electrons and light as ultra‑steady rulers

Quantum computers get a lot of attention, even though they are not ready for prime time, but quantum sensors are already doing useful work. These sensors measure fields, forces and motion so small that ordinary background noise can drown them out. Some sensors are already in daily use, while others are moving from research labs into flight tests, hospitals and field instruments.

For example, a human brain produces magnetic signals in the femtotesla-to-picotesla range—billions of times weaker than a refrigerator magnet—far weaker than the magnetic noise in an ordinary room. That is why brain scanners that measure these signals need ultrasensitive detectors and strong magnetic shielding. In some hospitals, these detectors use quantum technology to help map brain activity before epilepsy surgery, without touching the brain.

Quantum sensors are showing up in other fields as well, including in navigation when GPS signals are jammed or spoofed, mapping gravity to reveal what’s underground, and boosting astronomers’ ability to measure gravitational waves. I am a photonics and quantum technologies researcher. My lab applies physics to develop a range of devices, including quantum sensors.

Better helium reporting to improve fission and fusion materials modeling

Standardizing calculations of the helium byproducts generated in advanced fission and fusion energy system materials can increase reactor safety and longevity, according to a study led by University of Michigan Engineering with collaborators at Oak Ridge National Laboratory and its management contractor UT-Battelle.

Through a series of simulations, the researchers found that modeling assumptions and key alloy elements—like carbon, nitrogen and nickel—significantly influence helium generation predictions. If left unaddressed, excess helium in real-world reactors could lead to faster component failure as materials swell and become brittle.

“If used, our reporting methods will improve the experimental and modeling fidelity of the nuclear materials databases being generated both domestically and internationally, driving the rapid deployment of advanced nuclear,” said Kevin Field, a professor of nuclear engineering and radiological sciences at U-M and corresponding author of the study published in the Journal of Physics: Energy.

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