Scientists teasing through six billion particle smashups detect roughly 16 “antihyperhydrogen-4” particles.
Category: particle physics – Page 37
Most of Earth’s meteorites also trace their origins to S-type asteroids, yet they contain minimal organic material. This scarcity has made analyzing their organic content a significant challenge. In contrast, the Hayabusa mission’s meticulously curated samples are free from terrestrial interference, enabling groundbreaking studies of organic compounds.
Among the particles returned by Hayabusa, one named “Amazon” has proven particularly revealing. Measuring just 30 micrometers wide, Amazon offers a rare opportunity to investigate both water and organic content. Its unique shape, reminiscent of the South American continent, underscores its distinctiveness.
Amazon’s mineral composition includes olivine, pyroxenes, albite, and traces of high-temperature carbonates. These minerals confirm its origin as an S-type asteroid, linking it directly to ordinary chondrites.
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Blog post with audio player, show notes, and transcript: https://www.preposterousuniverse.com/podcast/2024/03/04/267-…f-reality/
In the 1860s, James Clerk Maxwell argued that light was a wave of electric and magnetic fields. But it took over four decades for physicists to put together the theory of special relativity, which correctly describes the symmetries underlying Maxwell’s theory. The delay came in part from the difficulty in accepting that light was a wave, but not a wave in any underlying “aether.” Today our most basic view of fundamental physics is found in quantum field theory, which posits that everything around us is a quantum version of a relativistic wave. I talk with physicist Matt Strassler about how we go from these interesting-but-intimidating concepts to the everyday world of tables, chairs, and ourselves.
Matt Strassler received his Ph.D. in physics from Stanford University. He is currently a writer and a visiting researcher in physics at Harvard University. His research has ranged over a number of topics in theoretical high-energy physics, from the phenomenology of dark matter and the Higgs boson to dualities in gauge theory and string theory. He blogs at Of Particular Significance, and his new book is Waves in an Impossible Sea: How Everyday Life Emerges from the Cosmic Ocean.
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Wearing sunscreen is important to protect your skin from the harmful effects of UV radiation but doesn’t cool people off. However, a new formula, described in Nano Letters, protects against both UV light and heat from the sun using radiative cooling. The prototype sunblock kept human skin up to 11 degrees Fahrenheit (6 degrees Celsius) cooler than bare skin, or around 6 °F (3 °C) cooler than existing sunscreens.
Radiative cooling involves either reflecting or radiating heat away from something, cooling whatever’s underneath. It is already used to create cooling fabrics and coatings that could both cool and heat homes, among other applications.
Some passive radiative cooling technologies rely on an ingredient called titanium dioxide (TiO2) because the whitish substance reflects heat. TiO2 particles are also used in mineral sunscreens to reflect UV light, but the particles aren’t the right size to produce a cooling effect. So, Rufan Zhang and colleagues wanted to tune the size of TiO2 nanoparticles to create a sunscreen that works both as a UV protector and a radiative cooler.
The ATLAS collaboration at the Large Hadron Collider (LHC) has released a new high-precision measurement of the lifetime of the electrically neutral beauty (B0) meson—a hadron composed of a bottom antiquark and a down quark.
Beauty (B) mesons are made up of two quarks, one of which is a bottom quark. Over the past decades, by studying B mesons, physicists have been able to examine rare and precisely predicted phenomena to gain insights into interactions mediated by the weak force and into the dynamics of heavy-quark bound states. The precise measurement of the B0 meson lifetime—the average time it exists before decaying into other particles—is of critical importance in this context.
The new ATLAS study of the B0 meson looked for the particle’s decay into an excited neutral kaon (K*0) and a J/ψ meson. The J/ψ meson subsequently decays into a pair of muons while the K*0 meson is studied through its decay into a charged pion and a charged kaon. The analysis is based on proton –proton collision data collected by the ATLAS detector during Run 2 of the LHC (2015–2018), amounting to an impressive data set of 140 inverse femtobarns (1 inverse femtobarn corresponds to approximately 100 trillion proton–proton collisions).
Queen Mary University of London physicist Professor Chris White, along with his twin brother Professor Martin White from the University of Adelaide, have discovered a surprising connection between the Large Hadron Collider (LHC) and the future of quantum computing.
For decades, scientists have been striving to build quantum computers that leverage the bizarre laws of quantum mechanics to achieve far greater processing power than traditional computers. A recently identified property—amusingly called “magic”—is critical for building these machines, but its generation and enhancement remain a mystery.
For any given quantum system, magic is a measure that tells us how hard it is to calculate on a non-quantum computer. The higher the magic, the more we need quantum computers to describe the behavior. Studying the magic properties of quantum systems generates profound insights into the development and use of quantum computers.
When two probes orbiting the sun aligned with one another, researchers harnessed the opportunity to track the sun’s magnetic field as it traveled into the solar system. They found that the sharply oscillating magnetic field smooths out to gentle waves while accelerating the surrounding solar wind, according to a University of Michigan-led study published in The Astrophysical Journal.
The sharp S-shaped bends of the magnetic fields streaming out of the sun, called magnetic switchbacks, have long been of interest to solar scientists. Switchbacks impact the solar wind —the charged particles, or plasma, that stream from the sun and influence space weather in ways that can disrupt Earth’s electrical grids, radio waves, radar and satellites.
The new understanding of magnetic switchback changes over time will help improve solar wind forecasts to better predict space weather and its potential impacts on Earth.
The magnetic moment of the muon is an important precision parameter for putting the Standard Model of particle physics to the test. After years of work, the research group led by Professor Hartmut Wittig of the PRISMA+ Cluster of Excellence at Johannes Gutenberg University Mainz (JGU) has calculated this quantity using the so-called lattice quantum chromodynamics method (lattice QCD method).
Their result agrees with the latest experimental measurements, in contrast to earlier theoretical calculations.
After the experimental measurements had been pushed to ever higher precision in recent years, attention had increasingly turned to the theoretical prediction and the central question of whether it deviates significantly from the experimental results and thus provides evidence for the existence of new physics beyond the Standard Model.
The orbital angular momentum states of light have been used to relate quantum uncertainty to wave–particle duality. The experiment was done by physicists in Europe and confirms a 2014 theoretical prediction that a minimum level of uncertainty must always result when a measurement is made on a quantum object – regardless of whether the object is observed as a wave, as a particle, or anywhere in between.
In the famous double-slit thought experiment, quantum particles such as electrons are fired on-by-one at two adjacent slits in a barrier. As time progresses, an interference pattern will build up on a detector behind the barrier. This is an example of wave–particle duality in quantum mechanics, whereby each particle travels through both slits as a wave that interferes with itself. However, if the trajectories of the particles are observed such that it is known which slit each particle travelled through, no interference pattern is seen. Since the 1970s, several different versions of the experiment have been done in the laboratory – confirming the quantum nature of reality.
Physicists have created a new and long-lasting magnetic state in a material, using only light. They used a terahertz laser to stimulate atoms in antiferromagnetic materials, which could advance information processing and memory chip technology.
Lighting Up Hidden Magnetism with Terahertz Pulses: A New Frontier in Quantum Materials.
Imagine being able to control the magnetic properties of materials with flashes of light, unlocking states that last long after the light disappears. This groundbreaking approach to quantum materials is at the forefront of condensed-matter physics, offering tantalizing possibilities for future technologies.
In a recent study, researchers discovered a way to create a long-lived magnetic state in the layered material FePS₃ using terahertz light pulses. Typically, materials return to their original state almost immediately after light-induced changes. However, in this case, the induced magnetization persists for over 2.5 milliseconds—an eternity in the quantum world.
The key lies in the material’s proximity to a critical point—its antiferromagnetic transition temperature, where the usual magnetic order starts to fluctuate dramatically. These fluctuations, akin to a system in delicate balance, seem to amplify the material’s response to light, stabilizing the new magnetic state.