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Scientists may have found the source of the most powerful neutrino ever detected

A record-shattering particle from deep space may have exposed some of the universe’s most extreme black hole engines. A mysterious particle from deep space has scientists buzzing after the most energetic neutrino ever detected slammed through the Mediterranean Sea. Now, researchers think they may have identified the cosmic “culprits” behind it: blazars — supermassive black holes blasting jets of matter straight toward Earth.

Three years ago, scientists detected something extraordinary deep beneath the Mediterranean Sea: the most energetic cosmic neutrino ever observed. The particle carried an astonishing energy of around 220 PeV, more than ten times greater than previously detected high energy neutrinos, and researchers still do not know exactly where it came from.

Now, a new study published in the Journal of Cosmology and Astroparticle Physics (JCAP) suggests the particle may have originated from blazars, some of the universe’s most extreme objects. Blazars are active galactic nuclei powered by supermassive black holes that shoot enormous jets of plasma directly toward Earth.

New light-based switch could cut chip energy use and speed future AI photonics

2D nanocavity exciton polaritons. (a) Schematic of the coupled TMD-PhC nanocavity. (b) Schematic of the gate-tunable TMD stack. © Scanning electron microscope image of the suspended Si3N4 nanobeam cavity, with the inset showing the simulated cavity mode profile. The dark area is suspended from the SiO2 substrate. Scale bar, 500 nm. Credit: Physical Review Letters (2026). DOI: 10.1103/gc15-qsvf.

Photonic devices are hardware systems that can process information using light instead of electricity. These systems could potentially perform computations faster than electronic devices, while also consuming less energy.

A key challenge faced by engineers developing photonic systems is achieving strong optical nonlinearities, or in other words, developing approaches that enable the control of light signals using light, all while consuming little power. A proposed solution to attain these light-light interactions entails the use of exciton polaritons, hybrid particles that are formed when photons couple with excitons (i.e., bound pairs of electrons and holes inside semiconductors).

Critical Te-104 decay measurements may help answer century-old alpha particle formation question

University of Tennessee, Knoxville physicists and their colleagues have made critical measurements of the lifetime and decay energy of tellurium-104 (Te-104), an important step in answering a century-old question and understanding how hundreds of nuclei decay. The results are published in Nature.

Professor Robert Grzywacz led the experimental team at the Radioactive Isotope Beam Factory (RIBF) at RIKEN in Japan. He explained how the results match decades-old predictions that tellurium-104 is a special case in alpha decay, a process where an alpha particle (a strongly bound system of two protons and two neutrons) tunnels through the barrier surrounding the nucleus where it resides. Though alpha radioactivity was discovered more than 125 years ago, where the particle comes from is still a mystery, especially in nuclei that have large numbers of protons and neutrons.

“Alpha decay is the oldest decay mode,” Grzywacz said. “The big question is how the alpha particle forms in heavy nuclei, which are known to have uniform matter distribution. There must be a mechanism which causes local ‘clump’ or ‘cluster’ formation.”

Light pulses uncover Higgs mode that reshapes perovskite crystal symmetry

Waves of light and sound interact to drive electronic and structural changes in a perovskite crystal. At the atomic scale, nothing is ever truly still. Materials that appear perfectly rigid and motionless to the naked eye are in fact swarms of vibrating atoms. This motion is generally random and uncoordinated, but with the right input, the atoms in certain materials will start to move together, vibrating in sync.

These collective vibrations are a form of sound called phonons, and when tuned just right, they can influence a material’s structure and behavior in dramatic and useful ways. Researchers are working to understand and control this effect to optimize material properties and even access hidden phases of matter.

Scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory are using light to drive phonon activity in a class of materials called metal halide perovskites, whose customizable structures and photosensitivity hold promise for use in next-generation solar cells, advanced sensors and quantum information technologies.

The delusion of a particle-only universe

If everything that happens in the world ultimately comes down to the behavior of fundamental particles, it would seem that other entities, from cells to human beings, from currencies to financial markets, aren’t really causing anything at all—that they are just shadows cast by patterns at the most fundamental level. But philosopher David Yates argues this conclusion is wrong. The whole affects the parts, and higher-level structures don’t just describe what is happening at lower levels in more convenient terms—they actively shape what is possible. This means that chemists, biologists, psychologists, and economists aren’t chasing shadows. They are studying structures that genuinely shape how the world unfolds.

In 1974, Jerry Fodor published a seminal paper titled ‘Special Sciences’, in which he argued for an intuitive and compelling picture of the relationship between fundamental physics and higher-level sciences such as biology, psychology and economics. Our world, according to Fodor, is arranged hierarchically, with fundamental physical particles at the bottom, combining to form molecules, which combine to form cells, which combine to form complex organisms, some of which have mental states, among them humans, who combine to form complex societies. The sciences are likewise arranged, with physics at the bottom, followed by chemistry, biology, physiology, neuroscience, psychology, sociology and economics. Now it is vanishingly unlikely, says Fodor, that things that share e.g. psychological or economic properties, also share some property specifiable in the language of physics or other lower-level sciences.

Quantum shell structure reveals new rule for proton-neutron pairing inside nuclei

Nuclear physicists used a little magic in their latest experiment conducted at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility, and the result has revealed surprising new information about the behavior of protons and neutrons inside the atom’s nucleus. Specifically, the research revealed another requirement that determines how protons and neutrons pair up.

The result is reported in the journal Nature.

The research involves short-range correlations (SRCs). This phenomenon describes when a proton and a neutron, or two protons or two neutrons, briefly pair up inside the nucleus.

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