An extremely precise detection method for single electrons, which pins down the particles with a resolution of trillionths of a second, may provide a valuable building block for future quantum technologies
Category: particle physics
As the atmosphere changes, so will its response to geomagnetic storms
Rising concentrations of carbon dioxide in the upper atmosphere will change the way geomagnetic storms impact Earth, with potential implications for thousands of orbiting satellites, according to new research led by scientists at the U.S. National Science Foundation National Center for Atmospheric Research (NSF NCAR).
Geomagnetic storms, caused by massive eruptions of charged particles from the surface of the sun that buffet Earth’s atmosphere, are a growing challenge for our technologically dependent society. The storms temporarily increase the density of the upper atmosphere and therefore the drag on satellites, which impacts their speed, altitude, and how long they remain operational.
The new study used an advanced computer model to determine that the upper atmosphere’s density will be lower during a future geomagnetic storm compared with a present-day storm of the same intensity. That’s because the baseline density will be lower, and future storms won’t increase it to levels as high as what occurs with storms currently.
Ripples of the future: Rice researchers unlock powerful form of quantum interference
Just as overlapping ripples on a pond can amplify or cancel each other out, waves of many kinds — including light, sound and atomic vibrations — can interfere with one another. At the quantum level, this kind of interference powers high-precision sensors and could be harnessed for quantum computing.
In a new study published in Science Advances, researchers at Rice University and collaborators have demonstrated a strong form of interference between phonons — the vibrations in a material’s structure that constitute the tiniest units, or quanta, of heat or sound in that system. The phenomenon where two phonons with different frequency distributions interfere with each other, known as Fano resonance, was two orders of magnitude greater than any previously reported.
“While this phenomenon is well-studied for particles like electrons and photons, interference between phonons has been much less explored,” said Kunyan Zhang, a former postdoctoral researcher at Rice and first author on the study. “That is a missed opportunity, since phonons can maintain their wave behavior for a long time, making them promising for stable, high-performance devices.”
Rice researchers have demonstrated a form of quantum interference two orders of magnitude greater than any previously reported.
A quantum gas that refuses to heat—physicists observe many-body dynamical localization
In everyday life, continuously doing work on a system is found to heat it up. Rubbing your hands together warms them. Hammering a piece of metal makes it hot. Even without knowing the equations, we learn from experience: driving any system, whether by stirring, pressing, or striking, leads to a rise in the system’s temperature.
The same expectation holds for microscopic quantum systems: when we continuously excite a many-particle system, especially one with strong particle-particle interactions, we expect it to absorb energy and to heat up. But is this always the case, in particular at the quantum level?
No, says an experiment carried out by a team from Hanns-Christoph Nägerl’s group at the Department of Experimental Physics of the University of Innsbruck. The research has been published in Science.
It’s Official: ‘Ghost Particle’ That Smashed Into Earth Breaks Records
The verdict is in. The detection of a cosmic neutrino that smashed into Earth with an unprecedented energy level is not a glitch or an error, but a real detection of a real particle.
In February 2023, a detector called KM3NeT, located deep under the Mediterranean Sea, picked up a signal that seemed to indicate a neutrino with a record-shattering energy of 220 petaelectronvolts (PeV). For reference, the previous record was a mere 10 PeV.
Now, an exhaustive analysis of all the data on and around the event, designated KM3-230213A, not only supports the conclusions that the signal was caused by a 220-PeV neutrino, but adds to the mystery about where the heck in the Universe it came from.
Is There Evidence For a Vast Multiverse?
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In 1987, Steven Weinberg wrote a cute little paper entitled “Anthropic Bound on the Cosmological Constant”. I say cute little paper because it feels minor in comparison to, say, electroweak unification theory that won him the Nobel Prize. Weinberg was foundational in establishing the standard model of particle physics, and represented an enormous leap in understanding how this universe works. But his little 1987 paper, though more obscure, may tell us something about how the multiverse works, and can even be thought of as evidence for the existence of an enormous number of other universes.
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Is Information a Fundamental Force of the Universe?
Researchers Robert Hazen and Michael Wong have put forward a bold new law of nature — one that could explain how everything in the universe evolves, from atoms, minerals and stars to living cells, ecosystems and even human civilization. At the heart of their theory is the idea that information is as fundamental to the cosmos as mass, energy or charge. Their law revolves around a concept called functional information — a measure of the ratcheting-up of complexity and function in evolving systems over time.
Wild New Theory Suggests Gravitational Waves Shaped The Universe
Just as ocean waves shape our shores, ripples in space-time may have once set the Universe on an evolutionary path that led to the cosmos as we see it today.
A new theory suggests gravitational waves – rather than hypothetical particles called inflatons – drove the Universe’s early expansion, and the redistribution of matter therein.
“For decades, we have tried to understand the early moments of the Universe using models based on elements we have never observed,” explains the first author of the paper, theoretical astrophysicist Raúl Jiménez of the University of Barcelona.