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Ultrafast Movie Reveals Unexpected Plasma Behavior

Using a camera with 2-picosecond time resolution, researchers show that the atoms in a laser-induced plasma are more highly ionized than theory predicts.

With an astonishing 500 billion frames per second, a new movie captures the evolution of a laser-induced plasma, revealing that its atoms have lost more electrons—and thus have stronger interactions within the plasma—than models predict [1]. The movie relies on a ten-year-old technology, called compressed ultrafast photography (CUP), that packs all the information for hundreds of movie frames into a single image. The results suggest that models of plasma formation may need revising, which could have implications for inertial-confinement-fusion experiments, such as those at the National Ignition Facility in California.

Dense plasmas occur in many astrophysical settings and laboratory experiments. Their behavior is difficult to predict, as they often change on picosecond (10−12 s) timescales. A traditional method for probing this behavior is to use a streak camera, which collects a movie on a single image by capturing a small slice of each movie frame. “It’s one picture, but every line occurs at a different time,” explains John Koulakis from UCLA. He and his colleagues have used streak cameras to study anomalous behavior in plasmas [2], but the small region of plasma visible with this technique left doubts about what they were seeing, he says.

Puzzling slow radio pulses are coming from space. A new study could finally explain them

Cosmic radio pulses repeating every few minutes or hours, known as long-period transients, have puzzled astronomers since their discovery in 2022. Our new study, published in Nature Astronomy today, might finally add some clarity.

Radio astronomers are very familiar with pulsars, a type of rapidly rotating neutron star. To us watching the skies from Earth, these objects appear to pulse because powerful radio beams from their poles sweep our telescopes—much like a cosmic lighthouse.

The slowest pulsars rotate in just a few seconds—this is known as their period. But in recent years, long-period transients have been discovered as well. These have periods from 18 minutes to more than six hours.

Why are Tatooine planets rare? General relativity explains why binary star systems rarely host planets

Astronomers have found thousands of exoplanets around single stars, but few around binary stars—even though both types of stars are equally common. Physicists can now explain the dearth.

Of the more than 4,500 stars known to have planets, one puzzling statistic stands out. Even though nearly all stars are expected to have planets and most stars form in pairs, planets that orbit both stars in a pair are rare.

Of the more than 6,000 extrasolar planets, or exoplanets, confirmed to date—most of them found by NASA’s Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS)—only 14 are observed to orbit binary stars. There should be hundreds. Where are all the planets with two suns, like Tatooine in Star Wars?

How a broken DNA repair tool accelerates aging

Although DNA is tightly packed and protected within the cell nucleus, it is constantly threatened by damage from normal metabolic processes or external stressors such as radiation or chemical substances. To counteract this, cells rely on an elaborate network of repair mechanisms. When these systems fail, DNA damage can accumulate, impair cellular function, and contribute to cancer, aging, and degenerative diseases.

One particularly severe form of DNA damage are the so-called DNA–protein crosslinks (DPCs), in which proteins become attached to DNA. DPCs can arise from alcohol consumption, exposure to substances such as formaldehyde or other aldehydes, or from errors made by enzymes involved in DNA replication and repair. Because DPCs can cause serious errors during cell division by stalling DNA replication, DNA–protein crosslinks pose a serious threat to genome integrity.

The enzyme SPRTN removes DPCs by cleaving the DNA-protein crosslinks. SPRTN malfunctions, for example as a result of mutations, may predispose individuals to developing bone deformities and liver cancer in their teenage years. This rare genetic disorder is known as Ruijs-Aalfs syndrome. Its underlying mechanism remains poorly understood, and there are no specific therapies.

Record-breaking photons at telecom wavelengths—on demand

A team of researchers from the University of Stuttgart and the Julius-Maximilians-Universität Würzburg led by Prof. Stefanie Barz (University of Stuttgart) has demonstrated a source of single photons that combines on-demand operation with record-high photon quality in the telecommunications C-band—a key step toward scalable photonic quantum computation and quantum communication. “The lack of a high-quality on-demand C-band photon source has been a major problem in quantum optics laboratories for over a decade—our new technology now removes this obstacle,” says Prof. Stefanie Barz.

In everyday life, distinguishing features may often be desirable. Few want to be exactly like everyone else. When it comes to quantum technologies, however, complete indistinguishability is the name of the game. Quantum particles such as photons that are identical in all their properties can interfere with each other—much as in noise-canceling headphones, where sound waves that are precisely inverted copies of the incoming noise cancel out the background.

When identical photons are made to act in synchrony, then the probability that certain measurement outcomes occur can be either boosted or decreased. Such quantum effects give rise to powerful new phenomena that lie at the heart of emerging technologies such as quantum computing and quantum networking. For these technologies to become feasible, high-quality interference between photons is essential.

Novel membrane boosts water electrolysis performance in low-alkalinity conditions

As green hydrogen emerges as a key next-generation clean energy source, securing technologies that enable its stable and cost-effective production has become a critical challenge. However, conventional water electrolysis technologies face limitations in large-scale deployment due to high system costs and operational burdens.

In particular, long-term operation often leads to performance degradation and increased maintenance costs, hindering commercialization. As a result, there is growing demand for new electrolysis technologies that can simultaneously improve efficiency, stability, and cost competitiveness.

A research team led by Dr. Dirk Henkensmeier at the Hydrogen and Fuel Cell Research Center of the Korea Institute of Science and Technology (KIST) has developed a novel membrane material for water electrolysis that operates stably and has significantly higher conductivity under low alkalinity conditions than existing systems.

Say what’s on your mind, and AI can tell what kind of person you are

If you say a few words, generative AI will understand who you are—maybe even better than your close family and friends. A new University of Michigan study found that widely available generative AI models (e.g., ChatGPT, Claude, LLaMa) can predict personality, key behaviors and daily emotions as or even more accurately than those closest to you. The findings appear in the journal Nature Human Behavior.

AI as a new personality judge

“What this study shows is AI can also help us understand ourselves better, providing insights into what makes us most human, our personalities,” said the study’s first author Aidan Wright, U-M professor of psychology and psychiatry. “Lots of people may find this of interest and useful. People have long been interested in understanding themselves better. Online personality questionnaires, some valid and many of dubious quality, are enormously popular.”

Study solves key micro-LED challenges, enabling ‘reality-like’ visuals for AR/VR devices

From TVs and smartwatches to rapidly emerging VR and AR devices, micro-LEDs are a next-generation display technology in which each LED—smaller than the thickness of a human hair—emits light on its own. Among the three primary colors required for full-color displays—red, green, and blue—the realization of high-performance red micro-LEDs has long been considered the most difficult.

KAIST researchers have successfully demonstrated a high-efficiency, ultra-high-resolution red micro-LED display, paving the way for displays that can deliver visuals even sharper than reality. The work is published in the journal Nature Electronics.

A research team led by Professor Sanghyeon Kim of the School of Electrical Engineering, in collaboration with Professor Dae-Myeong Geum of Inha University, compound-semiconductor manufacturer QSI, and microdisplay/SoC design company Raontech, has developed a red micro-LED display technology that achieves ultra-high resolution while significantly reducing power consumption.

Scientists teach microorganisms to build molecules with light

Researchers are continually looking for new ways to hack the cellular machinery of microbes like yeast and bacteria to make products that are useful for humans and society. In a new proof-of-concept study, a team from the Carl R. Woese Institute for Genomic Biology showed they can expand the biosynthetic capabilities of these microbes by using light to help access new types of chemical transformations.

The paper, published in Nature Catalysis, demonstrates how the bacteria Escherichia coli can be engineered to produce these new molecules in vivo, using light-driven enzymatic reactions. This framework sets the foundation for future development in the emerging field of photobiocatalysis.

“Photobiocatalysis is basically light-activated catalysis by enzymes. Without light, the target enzyme cannot catalyze a reaction. When light is added, the target enzyme will be activated,” said Huimin Zhao (BSD leader/CAMBERS/CGD/MMG), Steven L. Miller Chair of Chemical and Biomolecular Engineering. “We have published many papers showing that it is possible to combine photocatalysis with enzyme catalysis to create a new class of photoenzymes. These artificial photoenzymes can catalyze selective reactions that cannot be achieved by natural enzymes and are also very difficult, or sometimes even not possible, with chemical catalysis.”

Quantum mechanical effects help overcome a fundamental limitation of optical microscopy

Researchers from Regensburg and Birmingham have overcome a fundamental limitation of optical microscopy. With the help of quantum mechanical effects, they succeeded for the first time in performing optical measurements with atomic resolution. Their work is published in the journal Nano Letters.

From smartphone cameras to space telescopes, the desire to see ever finer detail has driven technological progress. Yet as we probe smaller and smaller length scales, we encounter a fundamental boundary set by light itself. Because light behaves as a wave, it cannot be focused arbitrarily sharply due to an effect called diffraction. As a result, conventional optical microscopes are unable to resolve structures much smaller than the wavelength of light, placing the very building blocks of matter beyond direct optical observation.

Now, researchers at the Regensburg Center for Ultrafast Nanoscopy, together with colleagues at the University of Birmingham, have found a novel way to overcome this limitation. Using standard continuous-wave lasers, they have achieved optical measurements at distances comparable to the spacing between individual atoms.

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