Toggle light / dark theme

Get the latest international news and world events from around the world.

Log in for authorized contributors

Geochemical research could help identify microbial activity in Earth’s rock record and perhaps in Martian sediments

Because oxygen-bearing sulfate minerals trap and preserve signals from Earth’s atmosphere, scientists closely study how they form. Sulfates are stable over billions of years, so their oxygen isotopes are seen as a time capsule, reflecting atmospheric conditions while they were evolving on early Earth—and possibly on its planetary neighbor Mars.

A new study led by a University of Utah geochemist examines how forms when pyrite, commonly known as “fool’s gold,” is oxidized in environments teeming with microbes versus those without them. The researchers focused on Spain’s Rio Tinto, a contaminated river passing through a region where iron and copper were mined for thousands of years.

The paper titled, “Triple-oxygen isotopic evidence of prolonged direct bioleaching of pyrite with O2,” appears in Earth and Planetary Science Letters.

Quantum Systems Modeled Without Prior Assumptions

An improved algorithm for learning the static and dynamic properties of a quantum system could have applications in quantum computing, simulation, and sensing.

Quantum systems are notoriously hard to study, control, and simulate. One key reason is that their full characterization requires a vast amount of information. Fortunately, in the past decade, scientists have shown that many physical properties of a quantum system can be efficiently predicted using much less information [1, 2]. Moreover, researchers have built quantum sensors that can measure these properties with a much smaller uncertainty compared with the best classical sensors [3]. Nevertheless, it has been difficult to achieve both efficient predictions and precise measurements at the same time. Now, building on previous breakthroughs in the field, Hong-Ye Hu at Harvard University and his colleagues have demonstrated a new algorithm that characterizes quantum systems of any size with optimal efficiency and precision [4].

Researchers help break thermal conductivity barrier with boron arsenide discovery

University of Houston researchers have made a discovery in thermal conductivity that overturns an existing theory that boron arsenide (BAs) couldn’t compete with the heat conduction of a diamond.

Instead, the team found that high-quality crystals can achieve exceeding 2,100 watts per meter per Kelvin (W/mK) at room temperature—possibly higher than diamond, which has been considered the best heat conductor among isotropic materials.

Published in Materials Today, this research challenges existing theories and could reshape our understanding of heat-conducting materials. It could also bring forth a new semiconductor material with much better thermal management in cell phones, high-powered electronics and .

Exploring how dark matter alters electron-capture supernovae and the birth of neutron stars

Electron-capture supernovae (ECSNe) are stellar explosions that occur in stars with initial masses around 8–10 times that of the sun. These stars develop oxygen-neon-magnesium cores, which become unstable when electrons are captured by neon and magnesium nuclei.

A tiny chip that can help us see deeper into space

A new imaging system could help us see deeper into the universe than ever before. The same powerful technology could also help us analyze the chemical makeup of everyday materials such as food and medicines much faster and with greater accuracy than current methods.

In a study published in the journal Nature, researchers from Tsinghua University in China have introduced a tiny device called RAFAEL (Reconfigurable, Adaptive, FAst and Efficient Lithium-niobate spectro-imager) that uses advanced photonics to capture light in exceptional detail with high speed.

RAFAEL is designed to dramatically improve spectroscopy, the technique used to study the and chemical composition of matter. It is used for everything from mapping to checking for contaminants in water and diagnosing diseases, and it works by breaking down the light that comes from an object and analyzing the different colors (wavelengths). While incredibly powerful, traditional spectrometers often face a trade-off: To get very fine detail you have to block much of the light. Or if you let in a lot of light, you lose resolution or sensitivity.

The key to why the universe exists may lie in an 1800s knot idea science once dismissed

In 1867, Lord Kelvin imagined atoms as knots in the aether. The idea was soon disproven. Atoms turned out to be something else entirely. But his discarded vision may yet hold the key to why the universe exists.

Now, for the first time, Japanese physicists have shown that can arise in a realistic particle physics framework, one that also tackles deep puzzles such as neutrino masses, , and the strong CP problem.

Their findings, in Physical Review Letters, suggest these “cosmic knots” could have formed and briefly dominated in the turbulent newborn universe, collapsing in ways that favored matter over antimatter and leaving behind a unique hum in spacetime that future detectors could listen for—a rarity for a physics mystery that’s notoriously hard to probe.

Secret QR codes and hidden warnings: 3D printing technique allows precise control of material properties, point by point

3D printing is extremely practical when you want to produce small quantities of customized components. However, this technology has always had one major problem: 3D printers can only process a single material at a time. Until now, objects with different material properties in different areas could only be 3D-printed at great expense, if at all.

Researchers at TU Wien have now developed methods for giving a 3D-printed object not only the desired shape, but also the desired material properties, point by point.

The versatility of this technology has been demonstrated in several applications: for example, it is possible to print an invisible QR code that only becomes visible at certain temperatures.

Physicists unlock secrets of stellar alchemy, yielding new insights into gold’s cosmic origins

You can’t have gold until a nucleus decays. The specifics of that process have been hard to pin down, but UT’s nuclear physicists have published three discoveries in one paper explaining key details. The results can help scientists come up with new models to describe the stellar processes that give us heavy elements, as well as make better predictions about the expanding landscape of exotic nuclei.

The work is published in the journal Physical Review Letters.

New organic thin-film tunnel transistors for wearable and other small electronics

To meet the growing demands of flexible and wearable electronic systems, such as smart watches and biomedical sensors, electronics engineers are seeking high-performance transistors that can efficiently modulate electrical current while maintaining mechanical flexibility.

Thin-film transistors (TFTs), which are comprised of thin layers of conducting, semiconducting and insulating materials, have proved to be particularly promising for large-area flexible and wearable electronics, while also enabling the creation of thinner displays and advanced sensors.

Despite their potential, the energy-efficiency with which these transistors can switch has proved difficult to improve. This is due to the so-called thermionic limit, a theoretical threshold that delineates the lowest possible voltage required for a transistor to boost electrical current by a factor of 10 at room temperature when switching between “off” and “on” states.

/* */