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Electrons oscillate around the nucleus of an atom on extremely short timescales, typically completing a cycle in just a few hundred attoseconds. Because of their ultrafast motions, directly observing electron behavior in molecules has been challenging. Now researchers from UC San Diego’s Department of Chemistry and Biochemistry have suggested a new method to make visualizing electron motion a reality.

This new method describes an experimental concept called ultrafast vortex electron diffraction, which allows for direct visualization of electron movement in molecules on attosecond timescales. The paper is published in the journal Physical Review Letters.

The key idea behind this approach is the use of a specialized electron beam that spirals as it travels, enabling precise tracking of electron motion in both space and time. This method is especially sensitive to electronic coherence, where electrons move in a synchronized, harmonious manner.

As the carriers of the weak force, the W and Z bosons are central to the Standard Model of particle physics. Though discovered four decades ago, the W and Z bosons continue to provide physicists with new avenues for exploration.

In a new study available on the arXiv preprint server, the ATLAS collaboration analyzed its full data set from the second run of the Large Hadron Collider (recorded from 2015 to 2018) in search of a rare process in which a Z boson is produced alongside two other weak-force carriers, or vector (V) bosons, as the W and Z are known.

“The production of three vector bosons is a very rare process at the LHC,” says Fabio Cerutti, ATLAS Physics Coordinator. “Its measurement provides information on the interactions among multiple bosons, which are linked to underlying symmetries of the Standard Model. This is a powerful tool for uncovering new physics phenomena, such as new, undiscovered particles that are too heavy to be directly produced at the LHC.”

1,337 seconds: that was how long WEST, a tokamak run from the CEA Cadarache site in southern France and one of the EUROfusion consortium medium size Tokamak facilities, was able to maintain a plasma for on 12 February. This was a 25% improvement on the previous record time achieved with EAST, in China, a few weeks previously.

Reaching durations such as these is a crucial milestone for machines like ITER, which will need to maintain fusion plasmas for several minutes. The end goal is to control the plasma, which is naturally unstable, while ensuring that all plasma-facing components are able to withstand its radiation without malfunctioning or polluting it.

This is what CEA researchers intend to achieve and what explains the current record. Over the coming months, the WEST team will double down on its efforts to achieve very long plasma durations—up to several hours combined—but also to heat the plasma to even higher temperatures with a view to approaching the conditions expected in fusion plasmas.

A study led by Professor Ginestra Bianconi from Queen Mary University of London, in collaboration with international researchers, has unveiled a transformative framework for understanding complex systems.

Published in Nature Physics, this paper establishes the new field of higher-order topological dynamics, revealing how the hidden geometry of networks shapes everything from brain activity to .

“Complex systems like the brain, climate, and next-generation artificial intelligence rely on interactions that extend beyond simple pairwise relationships. Our study reveals the critical role of higher-order networks, structures that capture multi-body interactions, in shaping the dynamics of such systems,” said Professor Bianconi.

When superconductors were discovered in 1911, they astounded researchers with their ability to conduct electricity with no resistance. However, they could only do so at temperatures close to absolute zero. But in 1986, scientists discovered that cuprates (a class of copper oxides) were superconductive at a relatively warm −225°F (above liquid nitrogen)—a step toward the ultimate goal of a superconductor that could operate at close to room temperature.

Applications of such a superconductor include compact and portable MRI machines, levitating trains, long-range electrical transmission without power loss, and more resilient quantum bits for quantum computers. Unfortunately, cuprates are a type of ceramic material which makes their application at industrial scales difficult—their brittleness, for example, would pose problems.

However, if researchers could understand what makes them superconduct at such high temperatures, they could recreate such processes in other materials. Despite a great deal of research, though, there is still a lack of consensus on the microscopic mechanism leading to their unusual superconductivity, making it difficult to take advantage of their unusual properties.

There is a big problem with quantum technology—it’s tiny. The distinctive properties that exist at the subatomic scale usually disappear at macroscopic scales, making it difficult to harness their superior sensing and communication capabilities for real-world applications, like optical systems and advanced computing.

Now, however, an international team led by physicists at Penn State and Columbia University has developed a novel approach to maintain special quantum characteristics, even in three-dimensional (3D) materials.

The researchers published their findings in Nature Materials.

The limitations of two-dimensional (2D) displays in representing the depth of the three-dimensional (3D) world have prompted researchers to explore alternatives that offer a more immersive experience. Volumetric displays (VDs), which generate 3D images using volumetric pixels (voxels), represent a breakthrough in this pursuit.

Unlike or stereoscopic displays, VDs deliver a natural visual experience without requiring head-mounted devices or complex visual tricks. Among these, laser-based VDs stand out for their , high contrast ratios, and wide color gamut. However, the commercial viability of such systems has been hindered by challenges such as low resolution, ghost voxels, and the absence of tunable, full-color emission in a single material.

To address these limitations, researchers from Yildiz Technical University, led by Miray Çelikbilek Ersundu, and Ali Erçin Ersundu, have developed innovative RE3+-doped monolithic glasses (RE = Ho, Tm, Nd, Yb) capable of tunable full-color emission under near-infrared (NIR) laser excitation.

Ever since physicist Ernest Rutherford discovered the atomic nucleus in 1911, studying its structure and behavior has remained a challenging task. More than a century later, even with today’s high-tech tools for researching nuclear physics, mysteries of the universe abound.

Relying on leading-edge detectors developed by researchers at the Department of Energy’s Oak Ridge National Laboratory, the scientific community pursues elusive nuclear processes to unlock persistent mysteries. Answers to questions they hope to resolve hold the potential to redefine the universe itself. Why does the universe contain more matter than antimatter? Can a particle be both a matter and antimatter version of itself? Is there a mismatch between what the Big Bang produced and what the Standard Model of particle physics suggests?

Long at the vanguard of international efforts to answer questions like these, ORNL’s contributions remain strong today. David Radford, head of the lab’s Fundamental Nuclear and Particle Physics section, is an internationally renowned expert in the field who has had an indelible impact on the development of germanium detectors. Vital experimentation tools at the forefront of fundamental physics research, germanium detectors are large, single crystals of germanium—a metallic element—used to detect radiation and enable incredibly precise energy measurements.

We say a message is incoherent when we can’t make it out, or when it doesn’t make sense. A scribbled note, a drunken argument or a conversation taking place five tables down in a crowded cafe might all be incoherent. In general, “coherent” means the opposite—consistent, connected, clear.

In science, the word coherence takes on more specific, mathematical definitions, but they all get at a similar concept: Something is coherent if it can be understood, if it forms a unified whole and if those first two qualities persist.

Scientists originally developed the concept of coherence to understand and describe the wave-like behavior of light. Since then, the concept has been generalized to other systems involving waves, such as acoustic, electronic and quantum mechanical systems.