The physics desk
Physics from the quantum to the cosmos: particle physics, quantum computing, astrophysics, cosmology and the discoveries that change what is possible.
Physicists at Cambridge and the U.S. Army Research Laboratory extended a theory called non-affine lattice dynamics with a 'memory' term and matched every measurement of PMMA's shear modulus ever made, from molecular dynamics through Brillouin light scattering down to slow laboratory bending tests.
Merons and antimerons had only ever been seen in thick oxide crystals. Now a semiconductor a few atoms thick hosts a whole network of them, and the team can tell which come from twist and which from strain.
A photon emitted by a qubit is loud at first and fades like a struck bell, which is exactly the wrong shape for the next qubit to absorb. Engineering the waveguide's dispersion reverses the pulse and pushes the absorption probability to 100% in theory.
Cosmic-ray observatories in Utah and Argentina have to guess how the first collision in the upper atmosphere unfolds. For a few days in July 2025, CERN stopped guessing and photographed it.
The HZDR and Synchrotron SOLEIL team produced 272-nanometer ultraviolet flashes with the exponential power growth that defines a true FEL. Next target: extreme ultraviolet for inspecting computer chips.
The atoms were cooled to billionths of a degree above absolute zero and confined to thousands of one-dimensional tubes. Flip the interaction from repulsive to attractive and clusters of six or more form; release the tubes and the strings fly apart, releasing the energy that bound them.
An Oxford-led analysis of ATLAS data reconstructed the Z bosons' spins from the electrons and muons they left behind. It is one of the highest-energy confirmations of entanglement ever recorded, a trillion times beyond tabletop photon experiments.
Titanium diselenide, strontium ruthenate and hole-doped diamond host low-energy electron waves called plasmons that amplify the faint kick a light dark matter particle would deliver, physicists report in Physical Review Letters. All three can be made today.
A University of Chicago team laid out the blueprint in PRX Quantum. Helium-3 is a fermion, which means it obeys the rules that keep particles from crowding into the same state, and the group hopes to have single atoms in optical tweezers within a year or two.
The first measurement to track both the energy and the momentum transfer of near-miss lead collisions shows a three-sigma suppression at the smallest scales. It fits gluon saturation, a prediction that has waited decades for a clean test.
The sideways shift depends only on the light's wavelength, not on how tightly the beam is focused. For trapped-ion quantum computers it is either a new source of error or a new way to couple qubits.
Nine years after proposing the test, a Birmingham–Perimeter team measured how rotation squashed the heavier object in GW241011. Rotating boson stars with quartic self-interactions cannot explain it.
'Complement sampling' hands a computer one answer from set A and asks for one from set B. A classical computer can only guess. A trapped-ion processor used a 'swapper' circuit and won, despite the noise.
Guiding cesium atoms along a 420-nanometer fiber lets a quantum motion sensor keep working through jolts that would break a free-falling version. A new silicon-pinned membrane design solves the heat problem that stalled the idea for decades.
A Turkish astrophysicist ran the sun's evolution with and without an early super-Earth falling in. Only the version that swallowed one matches the sun's sound-speed profile, its convection depth and its missing lithium at the same time.
Hebrew University physicists filmed fracture from its first appearance to explosive rupture and found the slow stage can take up 75% of the process. The same geometry may explain how earthquakes begin.
eROSITA's second data release stacks three full-sky scans from Spektr-RG's first 556 days, nearly doubling the original catalog. Paired with Sloan spectroscopy, it shows fast-growing black holes were more common in the early universe than expected.
An algorithm called kine stitched 116 VLBA observations of the blazar 3C 345 into a continuous polarized video with four times the resolution and 140 times the contrast, and the bright knots did not behave like shocks.
Ultra-deep imaging of Cloud-9 with the Gran Telescopio Canarias reached 31.4 magnitudes per square arcsecond and caps any stellar mass at 16,000 suns, against a million suns' worth of hydrogen.
Using the Large Binocular Telescope to read helium lines in 48 metal-poor galaxies, the LBT Yp Project pinned the primordial helium fraction at 0.2458 ± 0.0013, cut the uncertainty from about 2% to nearly 0.5%, and found no room for a fourth neutrino in the universe's first seconds.
Instead of coaxing fragile quantum states into existence, physicists sent bright classical light through a random optical network and counted photons one at a time on the way out, exposing hidden multiphoton quantum behavior with 861 measurable components that survives noise and loss.
Simulations of a single stripe in a cuprate model show electron pairing carried by 'spinon singlets.' Switch off the magnetism and the pairs vanish; switch it back and they return. The team predicts a two-lattice-site shift that microscopes can check.
Bosonic codes store quantum information in microwave fields instead of single qubits, but shaping those states has been painfully slow. A new 'quantum lattice gate' set does it in a single period of the control signal, on hardware that already exists.
French physicists at the CEA caught superionic ice, in which oxygen sits in a lattice while hydrogen flows like liquid, switching from a cubic to a hexagonal crystal above 200 gigapascals. The result is published in Physical Review Letters.
The 'hypersoft X-ray sources,' spotted in the Andromeda and Pinwheel galaxies and four ellipticals, pour out extreme ultraviolet light and may be the long-sought stars that become Type Ia supernovae. The paper is in Nature Astronomy.
The model combines axion-like particles with a violation of Lorentz invariance — and it predicts the photon arrived an hour late, which is what detectors saw.
Tokyo Metropolitan University mapped atomic oxygen with a laser and found production happening in the dark zones near the electrodes — and several times more of it reaching the target.
Physicists used entangled lambda hyperons to measure how often a strange quark turns into an up quark. The numbers still add up to one — and still disagree slightly with the older kaon measurements.
Researchers at the Paul Scherrer Institute switched the handedness of chiral phonons in a 40-nanometer barium titanate membrane with an electric field, and the new state survived after the field was switched off.
eRASSU J0608 pulses every 374 seconds. Its orbit is decaying at one of the fastest rates ever measured, which would make it one of the loudest gravitational-wave sources in the sky — if astronomers can work out how far away it is.