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Your ketchup will see you now: Solid-phase properties reveal when yield stress fluids start to flow

Pounding on the bottom of a glass bottle of ketchup is one of life’s small annoyances. Getting that sweet, red concoction from its solid phase to a liquid takes too long when you’re hungry and could even require messy strategies with a butter knife.

Now a team of scientists has shown that determining the point where the solid transitions to a liquid can be predicted from the properties of the alone. The research has been published in Physical Review Letters.

The new work focuses on yielding, a phenomenon where a solid-like material starts to behave like a liquid. “This behavior occurs constantly all around us, from desserts like custards that smoothly flow onto your spoon to personal care products like toothpaste that are easily squeezed out of tubes but hold their shape on your toothbrush,” Ryan Poling-Skutvik of the University of Rhode Island in the United States told Phys.org.

Close encounters of the galactic kind: Simulations suggest Milky Way and Andromeda may not collide after all

Scientists from Helsinki, Durham and Toulouse universities used data from NASA’s Hubble and the European Space Agency’s Gaia space telescopes to simulate how the Milky Way and Andromeda will evolve over the next 10 billion years.

The two galaxies are currently heading towards each other at a speed of about 100 kilometers per second.

A collision would be devastating for both galaxies, which would be destroyed, leaving behind a spheroidal pile of stars known as an elliptical galaxy.

Asteroseismology study uncovers new pulsation modes in ultra-massive white dwarf

Based on time-series photometry from three different telescopes, an international team of astronomers has performed a detailed asteroseismology study of WD J0049−2525—the most massive pulsating white dwarf. The study, published May 22 on the arXiv pre-print server, resulted in the detection of new pulsation modes of this white dwarf.

White dwarfs (WDs) are stellar cores left behind after a star has exhausted its and represent the final evolutionary stage for the vast majority of stars. Observations show that most WDs have primary spectral classification DA as they exhibit hydrogen-dominated atmospheres. However, a small fraction of WDs showcases traces of heavier elements.

In pulsating WDs, luminosity varies due to non-radial gravity wave pulsations within these objects. One subtype of pulsating WDs is known as DAVs, or ZZ Ceti stars, which have only hydrogen absorption lines in their spectra.

Supercomputer simulation reveals how merging neutron stars form black holes and powerful jets

Merging neutron stars are excellent targets for multi-messenger astronomy. This modern and still very young method of astrophysics coordinates observations of the various signals from one and the same astrophysical source. When two neutron stars collide, they emit gravitational waves, neutrinos and radiation across the entire electromagnetic spectrum. To detect them, researchers need to add gravitational wave detectors and neutrino telescopes to ordinary telescopes that capture light.

Precise models and predictions of the expected signals are essential in order to coordinate these observatories, which are very different in nature.

“Predicting the multi-messenger signals from binary neutron star mergers from first principles is extremely difficult. We have now succeeded in doing just that,” says Kota Hayashi, a postdoctoral researcher in the Computational Relativistic Astrophysics department at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in the Potsdam Science Park. “Using the Fugaku supercomputer in Japan, we have performed the longest and most complex simulation of a binary neutron star to date.”

Redefining physics to roll a ball vertically

Researchers from the University of Waterloo have achieved a feat previously thought to be impossible—getting a sphere to roll down a totally vertical surface without applying any external force.

The spontaneous rolling motion, captured by high-speed cameras, was an unexpected observation after months of trial, error, and theoretical calculations by two Waterloo research teams.

“When we first saw it happening, we were frankly in disbelief,” said Dr. Sushanta Mitra, a professor of mechanical and mechatronics engineering and executive director of the Waterloo Institute for Nanotechnology.

‘Space charge layer’ effect could boost solid-state battery performance

An emerging technology to make lithium-ion batteries safer and more powerful involves using solid rather than liquid electrolytes, the materials that make it possible for ions to move through the device to generate power.

A team of University of Texas at Dallas researchers and their colleagues have discovered that the mixing of small particles between two solid electrolytes can generate an effect called a “space charge layer,” an accumulation of electric charge at the interface between the two materials.

The finding could aid the development of batteries with solid electrolytes, called solid-state batteries, for applications including mobile devices and electric vehicles. The researchers published their study in ACS Energy Letters, where it is featured on the cover of the March issue.

Towards topological quantum batteries: Theoretical framework addresses two long-standing challenges

Researchers from the RIKEN Center for Quantum Computing and Huazhong University of Science and Technology have conducted a theoretical analysis demonstrating how a “topological quantum battery”—an innovative device that leverages the topological properties of photonic waveguides and quantum effects of two-level atoms—could be efficiently designed. The work, published in Physical Review Letters, holds promise for applications in nanoscale energy storage, optical quantum communication, and distributed quantum computing.

With increasing global awareness of the importance of environmental sustainability, developing next-generation storage devices has become a critical priority. Quantum batteries—hypothetical miniature devices that, unlike classical batteries that store energy via chemical reactions, rely on quantum properties such as superposition, entanglement, and coherence—have the potential to enhance the storage and transfer of energy.

From a mechanistic perspective, they offer potential performance advantages over classical batteries, including improved charging power, increased capacity, and superior work extraction efficiency.

Ultra-thin lenses halve incident wavelength to make infrared light visible

Physicists at ETH Zurich have developed a lens that can transform infrared light into visible light by halving the wavelength of incident light. The study is published in Advanced Materials.

Lenses are the most widely used optical devices. Camera lenses or objectives, for example, produce a sharp photo or video by directing at a focal point. The speed of evolution in the field of optics in recent decades is exemplified by the transformation of conventional bulky cameras into today’s compact smartphone cameras.

Even high-performance smartphone cameras still require a stack of lenses that often account for the thickest part of the phone. This size constraint is an inherent feature of classic design—a thick lens is crucial for bending light to capture a sharp image on the camera sensor.

Fusion project uses 3D-printed models to streamline assembly and reduce risk

The bundle of magnets at the heart of the U.S. Department of Energy’s Princeton Plasma Physics Laboratory’s (PPPL) National Spherical Torus Experiment-Upgrade (NSTX-U) is the star of the show.

Its magnets will produce the highest magnetic field of any large spherical torus, allowing for near steady-state conditions. They are critical to the design of NSTX-U. When it begins operating, it will be essential in determining whether spherical tokamaks, which are smaller and more compact than traditional doughnut-shaped tokamaks, could provide a more efficient and cost-effective model for a fusion pilot plant.

The 19-foot toroidal field (TF) magnet carries up to 4 million amps of electric current to stabilize and confine the superhot plasma in fusion experiments. It will eventually connect to 12 TF coils on the outside of the vacuum vessel. Wrapped around it like a slinky is the ohmic heating (OH) coil, a 4-kilovolt magnet that induces an , which drives an electric current into the vessel and helps to heat the plasma.

New data from ALICE may contribute to solving the cosmic muon puzzle

Cosmic rays are high-energy particles from outer space that strike Earth’s atmosphere, generating showers of secondary particles, such as muons, that can reach the planet’s surface. In recent years, ground-based experiments have detected more cosmic muons than current theoretical models predict, a discrepancy known as the muon puzzle.

Underground experiments offer good conditions for the detection of cosmic muons, because the rock or soil above the experiments absorbs the other shower components. They could therefore help to solve the muon puzzle. One example is ALICE at the Large Hadron Collider (LHC).

Designed to study the products of heavy-ion collisions, ALICE is also well-suited for detecting cosmic muons thanks to its location in a cavern 52 meters underground, shielded by 28 meters of overburden rock and an additional 1 meter of magnet yoke.