Lifeboat Foundation

A method for producing ultrashort, ultracold electron bunches could improve the resolution of electron-based imaging methods.

Quantum effects improve the performance of magnetic induction tomography—an imaging technique that has promising medical applications.

Micrometeoroids in Saturn’s rings reveal that these dusty bands are no more than 400 million years old, making them significantly younger than the 4.5-billion-year-old gas giant.

With its wide bands of encircling dust, Saturn’s rings are the biggest and brightest in our Solar System. They are also the most mysterious. Unanswered questions remain about why, how, and when the seven rings formed. Now Sascha Kempf of the University of Colorado Boulder and colleagues have addressed the latter problem, using dust contaminants within the rings to place an upper limit of 400 million years on the rings’ age [1]. Kempf says that for as long as he’s been in the field, astronomers have been discussing whether Saturn’s rings are as old as the planet or if they are younger. Now they know. “They are significantly younger,” he says.

Kempf and colleagues produced their age estimate by studying the contamination rate of the rings by small pieces of rock and debris, known as micrometeoroids. These contaminants are constantly zooming around our Solar System, colliding with objects in their paths. When one of these micrometeoroids hits one of Saturn’s rings it can get incorporated into the ice the rings contain. Kempf and colleagues realized they could use the rate at which this process happens as a clock to reveal the rings’ age.

A new search for an interaction between a particle’s intrinsic spin and Earth’s gravitational field probes physics in the regime where quantum theory meets gravity.

Our understanding of physics is supported by two theoretical pillars. The first is quantum field theory, which underpins the standard model of particle physics. And the second is Einstein’s theory of general relativity, which describes the nature of gravity. Both pillars have withstood numerous stringent tests and have had myriad predictions spectacularly confirmed. Yet they are seemingly irreconcilable, hinting at a deeper truth. The path toward reconciling these theories is obscured by the dearth of experiments probing phenomena at the intersection of quantum physics and gravity. Now a team of researchers from the University of Science and Technology of China (USTC), led by Dong Sheng and Zheng-Tian Lu, has stepped into this breach by searching for an interaction between a particle’s intrinsic quantum spin and Earth’s gravitational field with unprecedented sensitivity (Fig. 1) [1].

Over the past decades, researchers and companies worldwide have been trying to develop increasingly advanced quantum computers. The key objective of their efforts is to create systems that will outperform classical computers on specific tasks, which is also known as realizing “quantum advantage.”

A research team at D-Wave Quantum Inc., a Canadian quantum computing company, recently created a new quantum computing system that outperforms classical computing systems on optimization problems. This system, introduced in a paper in Nature, is based on a programmable spin glass with 5,000 qubits (the quantum equivalents of bits in classical computing).

“This work validates the original hypothesis behind quantum annealing, coming full circle from some seminal experiments conducted in the 1990s,” Andrew D. King, one of the researchers who carried out the study, told Phys.org.

AI tools based on artificial neural networks (ANNs) are being introduced in a growing number of settings, helping humans to tackle many problems faster and more efficiently. While most of these algorithms run on conventional digital devices and computers, electronic engineers have been exploring the potential of running them on alternative platforms, such as diffractive optical devices.

A research team led by Prof. Tie Jun Cui at Southeast University in China has recently developed a new programmable neural network based on a so-called spoof surface plasmon polariton (SSPP), which is a surface electromagnetic wave that propagates along planar interfaces. This newly proposed surface plasmonic neural network (SPNN) architecture, introduced in a paper in Nature Electronics, can detect and process microwaves, which could be useful for wireless communication and other technological applications.

“In digital hardware research for the implementation of artificial neural networks, optical neural networks and diffractive deep neural networks recently emerged as promising solutions,” Qian Ma, one of the researchers who carried out the study, told Tech Xplore. “Previous research focusing on optical neural networks showed that simultaneous high-level programmability and nonlinear computing can be difficult to achieve. Therefore, these ONN devices usually have been limited to specific tasks without programmability, or only applied for simple recognition tasks (i.e., linear problems).”

The first results from the James Webb Space Telescope have hinted at galaxies so early and so massive that they are in tension with our understanding of the formation of structure in the universe. Various explanations have been proposed that may alleviate this tension. But now a new study from the Cosmic Dawn Center suggests an effect which has never before been studied at such early epochs, indicating that the galaxies may be even more massive.

If you have been following the first results from the James Webb Space Telescope, you have probably heard about the paramount issue with the observations of the earliest galaxies: They are too big.

From a few days after the release of the first images, and repeatedly through the coming months, new reports of ever-more distant galaxies appeared. Disturbingly, several of the galaxies seemed to be “too massive.”

For more than a century, biologists have wondered what the earliest animals were like when they first arose in the ancient oceans more than half a billion years ago.

Searching among today’s most primitive-looking animals for the earliest branch of the animal tree of life, scientists gradually narrowed the possibilities down to two groups: sponges, which spend their entire adult lives in one spot, filtering food from seawater; and comb jellies, voracious predators that oar their way through the world’s oceans in search of food.

In a new study published this week in the journal Nature, researchers use a novel approach based on chromosome structure to come up with a definitive answer: Comb jellies, or ctenophores (pronounced teen’-a-fores), were the first lineage to branch off from the animal tree. Sponges were next, followed by the diversification of all other animals, including the lineage leading to humans.

What makes some materials carry current with no resistance? Scientists are trying to unravel the complex characteristics. Harnessing this property, known as superconductivity, could lead to perfectly efficient power lines, ultrafast computers, and a range of energy-saving advances. Understanding these materials when they aren’t superconducting is a key part of the quest to unlock that potential.

“To solve the problem, we need to understand the many phases of these materials,” said Kazuhiro Fujita, a physicist in the Condensed Matter Physics & Materials Science Department of the U.S. Department of Energy’s Brookhaven National Laboratory. In a new study just published in Physical Review X, Fujita and his colleagues sought to find an explanation for an oddity observed in a phase that coexists with the superconducting phase of a copper-oxide superconductor.

The anomaly was a mysterious disappearance of vibrational energy from the atoms that make up the material’s crystal lattice. “X-rays show that the atoms vibrate in particular ways,” Fujita said. But as the material is cooled, the X-ray studies showed, one mode of the vibrations stops.