Researchers have proposed that exotic particles emitted by the Large Hadron Collider’s relativistic beams might reveal themselves in collisions of their own.
Category: particle physics – Page 4
‘Singing’ electrons synchronize in Kagome crystals, revealing geometry-driven quantum coherence
Physicists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg have discovered a striking new form of quantum behavior. In star-shaped Kagome crystals—named after a traditional Japanese bamboo-basket woven pattern—electrons that usually act like a noisy crowd suddenly synchronize, forming a collective “song” that evolves with the crystal’s shape. The study, published in Nature, reveals that geometry itself can tune quantum coherence, opening new possibilities to develop materials where form defines function.
Quantum coherence—the ability of particles to move in synchrony like overlapping waves—is usually limited to exotic states such as superconductivity, where electrons pair up and flow coherently. In ordinary metals, collisions quickly destroy such coherence.
But in the Kagome metal CsV₃Sb₅, after sculpting tiny crystalline pillars just a few micrometers across and applying magnetic fields, the MPSD team observed Aharonov–Bohm-like oscillations in electrical resistance. Thus showing that electrons were interfering collectively, remaining coherent far beyond what single-particle physics would allow.
Seeking Signatures of Graviton Emission and Absorption
A proposed experiment may deliver evidence for the emission or absorption of gravitons—an advance that might one day enable gravity to be controlled much like electromagnetism is today.
A major milestone in human development was the transition from passively observing electromagnetic phenomena, such as electric discharges and magnetism, to actively manipulating them. This shift led to a plethora of applications—from power plants to modern electronics. The exquisite control of electromagnetic fields and of their interaction with matter has also yielded deep insights into the fundamental laws of nature, allowing us to test modern theories with remarkable precision. Now Ralf Schützhold of the Helmholtz-Zentrum Dresden-Rossendorf in Germany argues that a similar turning point may be reached for gravity [1]. His approach for manipulating gravity relies on experiments that can control the emission or absorption of gravitons, the hypothetical elementary particles mediating the gravitational interaction in a quantized theory of gravity.
AI efficiency advances with spintronic memory chip that combines storage and processing
To make accurate predictions and reliably complete desired tasks, most artificial intelligence (AI) systems need to rapidly analyze large amounts of data. This currently entails the transfer of data between processing and memory units, which are separate in existing electronic devices.
Over the past few years, many engineers have been trying to develop new hardware that could run AI algorithms more efficiently, known as compute-in-memory (CIM) systems. CIM systems are electronic components that can both perform computations and store information, typically serving both as processors and non-volatile memories. Non-volatile essentially means that they can retain data even when they are turned off.
Most previously introduced CIM designs rely on analog computing approaches, which allow devices to perform calculations leveraging electrical current. Despite their good energy efficiency, analog computing techniques are known to be significantly less precise than digital computing methods and often fail to reliably handle large AI models or vast amounts of data.
Mirrorless laser: Physicists propose a new light source
A team of physicists from the University of Innsbruck and Harvard University has proposed a fundamentally new way to generate laser light: a laser without mirrors. Their study, published in Physical Review Letters, shows that quantum emitters spaced at subwavelength distances can constructively synchronize their photon emission to produce a bright, very narrow-band light beam, even in the absence of any optical cavity.
In conventional lasers, mirrors are essential to bounce light back and forth, stimulating coherent emission from excited atoms or molecules, and thus light amplification. But in the new “mirrorless” concept, the atoms interact directly through their own electromagnetic dipole fields, given that interatomic spacing is smaller than the emitted light’s wavelength. When the system is pumped with enough energy, these interactions cause the emitters to lock together and radiate collectively—a phenomenon called superradiant emission.
The team led by Helmut Ritsch found that this collective emission generates light that is both highly directional and spectrally pure, with a single narrow spectral line, in cases where only a fraction of emitters are excited by a laser and the rest of atoms remain unpumped. Since this passive emitter fraction is not broadened by the driving laser or power broadening, it effectively acts as an optical resonator for the active emitters, in analogy with a conventional laser where the optical resonator and the gain medium are separate physical entities.
Memristors achieve stable resistance values tied to fundamental constants of nature
Researchers at Forschungszentrum Jülich, together with international collaborators, have demonstrated for the first time that memristors—novel nanoscale switching devices—can provide stable resistance values directly linked to fundamental constants of nature. This paves the way for electrical units such as electrical resistance to be traced back far more simply and directly than it has been possible to date. By contrast, conventional, quantum-based measurement technology is so demanding that it can only be carried out in a few specialized laboratories worldwide.
The paper is published in the journal Nature Nanotechnology.
Since 2019, all base units of the International System of Units (SI)—including the meter, second, and kilogram—have been based on fundamental natural constants. For example, the kilogram, which was once based on the “prototype kilogram,” is now linked to Planck’s constant h. A meter is defined by the speed of light, and a second by the oscillation of the cesium atom.
Quantum Echo: Nobel Prize in Physics Goes to Quantum Computer Trio (Two from Google) Who Broke Through Walls Forty Years Ago
Editor’s Note: EDRM is proud to publish Ralph Losey’s advocacy and analysis. The opinions and positions are Ralph Losey’s copyrighted work. All images in the article are by Ralph Losey using AI. This article is published here with permission.]
The Nobel Prize in Physics was just awarded to quantum physics pioneers John Clarke, Michel H. Devoret, and John M. Martinis for discoveries they made at UC Berkeley in the 1980s. They proved that quantum tunneling, where subatomic particles can break through seemingly impenetrable barriers, can also occur in the macroscopic world of electrical circuits. So yes, Schrödinger’s cat really could die.
