A possible method for probing the properties of exotic particles that exist on the surfaces of an unusual type of superconductor has been theoretically proposed by two RIKEN physicists.
The paper is published in the journal Physical Review B.
When cooled to very low temperatures, two or more electrons in some solids start to behave as if they were a single particle.
At least two mass extinction events in Earth’s history were likely caused by the “devastating” effects of nearby supernova explosions, a new study suggests.
Researchers at Keele University say these super-powerful blasts—caused by the death of a massive star—may have previously stripped our planet’s atmosphere of its ozone, sparked acid rain and exposed life to harmful ultraviolet radiation from the sun.
They believe a supernova explosion close to Earth could be to blame for both the late Devonian and Ordovician extinction events, which occurred 372 and 445 million years ago respectively.
Scientists have identified a promising new way to detect life on faraway planets, hinging on worlds that look nothing like Earth and gases rarely considered in the search for extraterrestrials.
In a new Astrophysical Journal Letterspaper, researchers from the University of California, Riverside, describe these gases, which could be detected in the atmospheres of exoplanets—planets outside our solar system—with the James Webb Space Telescope, or JWST.
Called methyl halides, the gases comprise a methyl group, which bears a carbon and three hydrogen atoms, attached to a halogen atom such as chlorine or bromine. They’re primarily produced on Earth by bacteria, marine algae, fungi, and some plants.
Imagine a universe where gravity isn’t a mysterious curvature of spacetime but an emergent force born directly from quantum mechanics. In a bold new paper, we take a journey that challenges our traditional view of gravity by deriving a four-dimensional force — a relativistic extension of the de Broglie-Bohm quantum force — that could reproduce gravitational phenomena even in the weak-field limit of General Relativity.
Sign Up on Patreon to get access to the Space Time Discord! / pbsspacetime.
Superconductive materials seem miraculous. Their resistanceless flow of electricity has been exploited in some powerful ways—from super-strong magnets used in MRIs, particle accelerators and fusion plants. And then there’s, their bizarre ability to levitate in magnetic fields. But the broader use of superconductors is limited because they need to be cooled to extremely low temperatures to work. But what if we could produce superconductivity at room temperature? It would change the world.
Cosmologists have a standard set of puzzles they think about: the nature of dark matter and dark energy, whether there was a period of inflation, the evolution of structure, and so on. But there are also even deeper questions, having to do with why there is a universe at all, and why the early universe had low entropy, that most working cosmologists don’t address. Today’s guest, Anthony Aguirre, is an exception. We talk about these deep issues, and how tackling them might lead to a very different way of thinking about our universe. At the end there’s an entertaining detour into AI and existential risk.
Anthony Aguirre received his Ph.D. in Astronomy from Harvard University. He is currently associate professor of physics at the University of California, Santa Cruz, where his research involves cosmology, inflation, and fundamental questions in physics. His new book, Cosmological Koans, is an exploration of the principles of contemporary cosmology illustrated with short stories in the style of Zen Buddhism. He is the co-founder of the Foundational Questions Institute, the Future of Life Institute, and the prediction platform Metaculus.
Two of the participants met the definition of partial success at 12 and 18 months, and the overall success of CALEC was 93% at 12 months and 92% at 18 months. Three participants received a second corneal CALEC transplant, of which one experienced complete success by the end check-up visit of the study.
Additional analysis of the impact of CALEC on vision showed varying levels of improvement of visual acuity in all 14 of the participants. The corneal procedure displayed a high safety profile with no adverse events occurring. However, one participant had a bacterial infection eight months after transplant due to chronic contact lens use. Any other adverse events were minor and were resolved quickly.
The CALEC trial is the first human study of a stem cell therapy to be funded by the National Eye Institute (NEI) branch of the NIH. However, the CALEC procedure remains an experimental procedure and it is not offered at Mass Eye and Ear or at any other hospital in America. Mass General Brigham’s Gene and Cell Therapy Institute will be conducting additional randomized-control design studies including a larger number of participants at multiple centers, with longer follow-ups before this treatment will be submitted for federal approval.
Plasmonic modulators are tiny components that convert electrical signals into optical signals in order to transport them through optical fibers. A modulator of this kind had never managed to transmit data at a frequency of over a terahertz (over a trillion oscillations per second).
Now, researchers from the group led by Jürg Leuthold, Professor of Photonics and Communications at ETH Zurich, have succeeded in doing just that. Previous modulators could only convert frequencies up to 100 or 200 gigahertz—in other words, frequencies that are five to ten times lower.
With today’s data rates of only a few hundred megabytes per second, access to digital information remains relatively slow. Initial experiments have already shown a promising new strategy: Magnetic states can be read out by short current pulses, whereby recently discovered spintronic effects in purpose-built material systems could remove previous speed restrictions.
Researchers at HZDR and TU Dortmund University are now providing proof of the feasibility of such ultrafast data sources. Instead of electrical pulses, they use ultrashort terahertzlight pulses, thereby enabling the read-out of magnetic structures within picoseconds, as they report in the journal Nature Communications.
“We now can determine the magnetic orientation of a material much quicker with light-induced current pulses,” explains Dr. Jan-Christoph Deinert of HZDR’s Institute of Radiation Physics. For their experiments, the physicist and his team employed light that is invisible to the human eye—so-called terahertz radiation.
An international team of researchers affiliated with UNIST has unveiled a novel cross-linker additive that significantly addresses the longstanding stability issues associated with organic solar cells, also known as organic photovoltaics (OPVs).
With the incorporation of just 0.05% of this cross-linking agent, the lifespan of OPVs can be improved by over 59%. Industry analysts suggest this breakthrough brings the commercialization of OPVs—regarded as next-generation solar cells—closer to reality.
Led by Professor BongSoo Kim in the Department of Chemistry at UNIST, the research team, in collaboration with researchers from the University of California, Santa Barbara (UCSB), the University of Lille in France, and the French National Center for Scientific Research (CNRS), identified the operational principles of this innovative cross-linker using a variety of advanced analytical techniques.