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Archive for the ‘particle physics’ category: Page 147

Oct 19, 2022

The Many-Worlds Theory, Explained

Posted by in categories: information science, particle physics, quantum physics

Quantum physics is strange. At least, it is strange to us, because the rules of the quantum world, which govern the way the world works at the level of atoms and subatomic particles (the behavior of light and matter, as the renowned physicist Richard Feynman put it), are not the rules that we are familiar with — the rules of what we call “common sense.”

The quantum rules, which were mostly established by the end of the 1920s, seem to be telling us that a cat can be both alive and dead at the same time, while a particle can be in two places at once. But to the great distress of many physicists, let alone ordinary mortals, nobody (then or since) has been able to come up with a common-sense explanation of what is going on. More thoughtful physicists have sought solace in other ways, to be sure, namely coming up with a variety of more or less desperate remedies to “explain” what is going on in the quantum world.

These remedies, the quanta of solace, are called “interpretations.” At the level of the equations, none of these interpretations is better than any other, although the interpreters and their followers will each tell you that their own favored interpretation is the one true faith, and all those who follow other faiths are heretics. On the other hand, none of the interpretations is worse than any of the others, mathematically speaking. Most probably, this means that we are missing something. One day, a glorious new description of the world may be discovered that makes all the same predictions as present-day quantum theory, but also makes sense. Well, at least we can hope.

Oct 16, 2022

Physicists predict the novel entangled states on programmable quantum simulators

Posted by in categories: computing, particle physics, quantum physics

Quantum science has not only deepened human understanding of the structure of matter and its microscopic interactions, but also introduced a new paradigm of computing and information science—quantum computing and quantum simulation. Quantum informatics research has won the 2022 Nobel Prize in Physics.

Among many and simulation platforms, Rydberg Atom Arrays is considered the most promising system to show quantum superiority among many programmable quantum simulator platforms in recent years due to its largest number of qubits and highest experimental accuracy.

Such optical lattices consist of individual neutral alkaline-earth atoms with significant dipole moments trapped in arrays of microscopic dipole traps, which can be optically moved at will to make desired lattice geometry. Each atom can be excited to its Rydberg state, and a pair of excited states interact through their dipole moments via a long-range interaction.

Oct 16, 2022

Quantum Entanglement Has Now Been Directly Observed at The Macroscopic Scale

Posted by in categories: particle physics, quantum physics

Quantum entanglement is the binding together of two particles or objects, even though they may be far apart – their respective properties are linked in a way that’s not possible under the rules of classical physics.

It’s a weird phenomenon that Einstein described as “spooky action at a distance”, but its weirdness is what makes it so fascinating to scientists. In a 2021 study, quantum entanglement was directly observed and recorded at the macroscopic scale – a scale much bigger than the subatomic particles normally associated with entanglement.

The dimensions involved are still very small from our perspective – the experiments involved two tiny aluminum drums one-fifth the width of a human hair – but in the realm of quantum physics they’re absolutely huge.

Oct 14, 2022

Annihilation of exceptional points from various degeneration points observed for the first time

Posted by in categories: particle physics, quantum physics

A team of researchers from the University of Warsaw in Poland, the Institute Pascal CNRS in France, the Military University of Technology in Poland and the British University of Southampton has shown that it is possible to control the so-called exceptional points. For the first time, physicists also observed the annihilation of exceptional points from different degeneracy points. You can read about the discovery that may contribute to the creation of modern optical devices in the latest Nature Communications.

The universe around us is made of , most of which have their antiparticles. When a particle and an antiparticle, that is, matter and antimatter, meet each other, annihilation occurs. Physicists have long been able to produce quasiparticles and quasiantiparticles—elementary excitations: charge, vibration, energy—trapped in matter, most often in crystals or liquids.

“The world of quasiparticles can be very complicated, although paradoxically, the quasiparticles themselves help simplify the description of quantum phenomena,” explains Jacek Szczytko from the Faculty of Physics at the University of Warsaw.

Oct 14, 2022

Fluctuation relations for irreversible emergence of information

Posted by in categories: biological, nanotechnology, particle physics, quantum physics

Information variations in a chain-like system are associated to energy transactions with the environment, which can take place reversibly or irreversibly, with a lower theoretical energy limit22,23. Fluctuations as a consequence of pure computations are on the order of the thermal level (i.e., similar to kT, being k the Boltzmann constant and T the absolute temperature), according to Landauer’s principle. Such energies are negligible at routine human scales but become significant when the size of the system is nanoscopic or smaller, because the work and heat it generates also compare with the thermal level. Small systems are based on nanostructures, including individual molecules and arrangements of atoms, such as biological and quantum systems.

Fluctuation theorems have appeared in recent years explaining quantitatively energy imbalances between forward and reverse pathways or between equilibrium and non-equilibrium processes24,25. They have been tested experimentally26,27,28, mostly in biomolecular systems analyzed on a one-by-one basis29. Most of these theorems establish relations among thermodynamic potentials for general systems, often with no specific insight into information theory. This theory, in turn, deals with spatially-indexed, 1-dimensional arrangements of symbols, which may not be necessarily associated to a time order. Recent generalizations separate the role of information and feedback control30,31, but still the interpretation of non-Markovianity, irreversibility and reversibility in terms of purely informational operations such as reading, writing and error correction32,33 remains obscured.

Here, we analyze energy exchanges associated to the symbolic management of a sequence of characters, without reference to the physical construction of the chain. Just by considering reversibility at the single sequence level and conservation laws, we next present two pairs of fluctuations equalities in the creation of information sequences, which use depends on energy exchange constraints. Our analysis integrates key information concepts, namely, reading, writing, proof reading and editing in the thermodynamic description of a string of symbols with information.

Oct 14, 2022

Potential Dark Matter Signal Gives Way to New Limits

Posted by in categories: cosmology, particle physics

Results from two leading dark matter experiments—XENONnT and PandaX-4T—rule out an enigmatic signal detected in 2020 and set new constraints on dark matter particle candidates consisting of light fermions, respectively.

Oct 14, 2022

An Absorbing Dark Matter Experiment

Posted by in categories: cosmology, particle physics

Over the past decade, physicists have repeatedly scrutinized tanks containing tons of liquid xenon, hoping to spot the flashes of light that might indicate a collision between a dark matter particle and a xenon atom (see Viewpoint: Dark Matter Still at Large). Most of these studies were dedicated to detecting so-called weakly interacting massive particles (WIMPs), a leading dark matter candidate with a mass greater than 10 GeV. Now researchers have sifted through a new set of data for a much lighter prize: fermionic dark matter with a mass of a few tens of MeV [1]. Although the team found no signal beyond the expected background level, they have set the strongest constraints yet on models of sub-GeV fermionic dark matter.

The dataset is the first obtained by the PandaX-4T experiment at the China Jinping Underground Laboratory. The PandaX team searched this data for evidence of a beyond-the-standard-model interaction in which a fermionic dark matter particle is absorbed by the nucleus of a xenon atom. After the absorption, the xenon nucleus should recoil while emitting either a neutrino or an antineutrino. The interaction should also cause an energy deposition in the form of photons and electrons, which would register on photodetectors at the ends of the tank. Unlike the scattering of WIMPs, which is predicted to produce a broad-spectrum energy deposition, the absorption by nuclei of fermionic dark matter particles should deposit energy only in a narrow range.

The data collected so far represent the equivalent of exposing 0.6 tons of liquid xenon to hypothetical fermionic dark matter for one year. When PandaX-4T concludes in 2025, it will have achieved a cumulative exposure 10 times greater, generating even stronger constraints on theory.

Oct 13, 2022

Tiny Particles Work Collectively To Generate Complex Behavior

Posted by in categories: education, particle physics, robotics/AI

Simple microparticles can beat rhythmically together, generating an oscillating electrical current that could be used to power micro-robotic devices.

MIT is an acronym for the Massachusetts Institute of Technology. It is a prestigious private research university in Cambridge, Massachusetts that was founded in 1861. It is organized into five Schools: architecture and planning; engineering; humanities, arts, and social sciences; management; and science. MIT’s impact includes many scientific breakthroughs and technological advances. Their stated goal is to make a better world through education, research, and innovation.

Oct 13, 2022

The world’s largest digital camera will capture a dust particle on the Moon

Posted by in categories: particle physics, space

All its mechanical components are now together for the first time.

Good news! The largest digital camera in the world is nearly ready to be mounted on its telescope. At the SLAC National Accelerator Laboratory, technicians are finishing up the largest digital camera in the world. The camera will be shipped to Chile and mounted on a telescope located in the Andes. The project was started a couple of years ago.

Even though the camera isn’t finished yet, all of its mechanical parts have now, for the first time, been assembled into a visually appealing framework.

Continue reading “The world’s largest digital camera will capture a dust particle on the Moon” »

Oct 13, 2022

Quantum Computing Breakthrough: Qubits for a Programmable, Solid-State Superconducting Processor

Posted by in categories: computing, particle physics, quantum physics

Long-Lived Coherent Quantum States in a Superconducting Device for Quantum Information Technology

Scientists have been able to demonstrate for the first time that large numbers of quantum bits, or qubits, can be tuned to interact with each other while maintaining coherence for an unprecedentedly long time, in a programmable, solid-state superconducting processor. This breakthrough was made by researchers from Arizona State University and Zhejiang University in China, along with two theorists from the United Kingdom.

Previously, this was only possible in Rydberg atom.