Blog

Archive for the ‘particle physics’ category: Page 24

Sep 23, 2024

Disorder Induces Delocalization

Posted by in categories: particle physics, quantum physics

A Bose-Einstein condensate of cold atoms occupying a periodic lattice can flow like a superfluid. But if the atoms’ mutual repulsion is strengthened and the lattice potential deepened, the atoms can become immobilized in a state known as a Mott insulator. Now Hepeng Yao of the University of Geneva and his collaborators have examined the Mott transition of cold atoms trapped in a lattice that is quasiperiodic rather than periodic [1]. Given that quasiperiodicity and other kinds of disorder tend to trap particles, the researchers were surprised to discover that their quasiperiodic lattice sustained the superfluid state rather than weakening it.

Yao and his collaborators trapped potassium-39 atoms in a one-dimensional optical lattice formed by the standing waves of two lasers. If the ratio of the lasers’ wavelengths was a rational number, the lattice was periodic. Otherwise, the lattice was quasiperiodic. By adjusting various experimental parameters, they could control the depth of the confining potentials, the strength of the interatomic repulsion, and whether the lattice sites were fully occupied. To determine whether a given set of parameters yielded a static, insulating state or a mobile, superfluid one, they turned off the trap and observed how the atoms flew apart.

The team found that the Mott transitions for the periodic and quasiperiodic lattices were both characterized by a critical value of the interparticle repulsion, but the critical value in the quasiperiodic case was higher. Quantum Monte Carlo simulations pointed to the reason. The commensurability between the lattice period and the particle number is a key factor in pinning particles in a Mott insulator. However, the quasiperiodic lattice blurs this commensurate period, thereby destabilizing the Mott phase to the profit of the superfluid one.

Sep 23, 2024

Researchers observe an antiferromagnetic diode effect in even-layered MnBi₂Te₄

Posted by in categories: computing, particle physics

Antiferromagnets are materials in which the magnetic moments of neighboring atoms are aligned in an alternating pattern, resulting in no net macroscopic magnetism. These materials have interesting properties that could be favorable for the development of spintronic and electronic devices.

Sep 23, 2024

New results from the CMS experiment put W boson mass mystery to rest

Posted by in category: particle physics

After an unexpected measurement by the Collider Detector at Fermilab (CDF) experiment in 2022, physicists on the Compact Muon Solenoid experiment (CMS) at the Large Hadron Collider (LHC) announced today a new mass measurement of the W boson, one of nature’s force-carrying particles.

Sep 23, 2024

New measurement of the top quark from LHC data

Posted by in category: particle physics

Researchers from the School of Physics & Astronomy have been involved in an important new measurement of the top quark made using data provided by the Large Hadron Collider (LHC).

Sep 22, 2024

Even the heaviest particles experience the usual quantum weirdness, new experiment shows

Posted by in categories: particle physics, quantum physics

One of the most surprising predictions of physics is entanglement, a phenomenon where objects can be some distance apart but still linked together. The best-known examples of entanglement involve tiny chunks of light (photons), and low energies.

Sep 22, 2024

Light has been seen leaving an atom cloud before it entered

Posted by in category: particle physics

Particles of light can spend “negative time” passing through a cloud of extremely cold atoms – without breaking the laws of physics.

By Karmela Padavic-Callaghan

Sep 22, 2024

Bridging the Gap: How Quantum Physics Supports Metaphysical Science and Why the Scientific Community Should Embrace This Integration

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

In the ever-evolving landscape of scientific discovery, certain paradigms periodically challenge the established norms, compelling us to reconsider the boundaries of what we deem as ‘science.’ One such paradigm is the intersection of quantum physics and metaphysical science. Despite skepticism, there is a growing body of evidence suggesting that these two fields are not only compatible but also complementary. This blog delves into how quantum physics supports metaphysical science and argues for its integration into mainstream scientific discourse, underpinned by historical precedents.

“The day science begins to study non-physical phenomena; it will make more progress in one decade than in all the previous centuries of its existence.” — Nikola Tesla

Quantum physics, the study of particles at the smallest scales of energy levels, has fundamentally altered our understanding of reality. The principles of quantum mechanics, such as superposition, entanglement, and wave-particle duality, have revealed a universe far more intricate and interconnected than classical physics ever suggested. These concepts resonate profoundly with metaphysical science, which explores the nature of reality, consciousness, and existence beyond the physical.

Sep 22, 2024

Bubbling, frothing and sloshing: Long-Hypothesized Plasma Instabilities Finally Observed

Posted by in categories: cosmology, nuclear energy, particle physics

Results could aid understanding of how black holes produce vast intergalactic jets. Scientists have observed new details of how plasma interacts with magnetic fields, potentially providing insight into the formation of enormous plasma jets that stretch between the stars.

Whether between galaxies or within doughnut-shaped fusion devices known as tokamaks, the electrically charged fourth state of matter known as plasma regularly encounters powerful magnetic fields, changing shape and sloshing in space. Now, a new measurement technique using protons, subatomic particles that form the nuclei of atoms, has captured details of this sloshing for the first time, potentially providing insight into the formation of enormous plasma jets that stretch between the stars.

Scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) created detailed pictures of a magnetic field bending outward because of the pressure created by expanding plasma. As the plasma pushed on the magnetic field, bubbling and frothing known as magneto-Rayleigh Taylor instabilities arose at the boundaries, creating structures resembling columns and mushrooms.

Sep 21, 2024

The Large Hadron Collider exposes quarks’ quantum entanglement

Posted by in categories: particle physics, quantum physics

Top quarks and antiquarks produced in the Large Hadron Collider are entangled, a study shows.

Sep 20, 2024

Probing the Quantum Nature of Reality

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

Even those of us who aren’t physicists have an intuitive understanding of classical physics — we can predict what will happen when we throw a ball, use a salad spinner, or ease up on the gas pedal.

But atomic and subatomic particles don’t follow these ordinary rules of reality. “It turns out that at really small scales there are a different set of rules called quantum physics,” said Travis Nicholson. “These rules are bizarre and interesting.” (Think Schrodinger’s cat and Einstein’s “spooky action at a distance.”)

Nicholson is an assistant professor with joint appointments in Physics and Electrical and Computer Engineering. The physicist in him likes doing experiments to advance our knowledge of quantum mechanics; the engineer in him likes figuring out how to harness that knowledge to build quantum computers that will be vastly more powerful than today’s computers.

Page 24 of 594First2122232425262728Last