Computer simulations of high-energy particles are pushing the boundaries of what we can learn about the interactions that happen inside particle colliders
Category: particle physics – Page 66
Scientists steer single atoms on magnetic surfaces for first time
Scientists in Germany have achieved a world first by moving individual atoms from one position to a precisely defined final one using magnetism, unlocking the potential for controlled atomic motion in nanotechnology and data storage.
The research team from the University of Kiel (CAU) and the University of Hamburg used a highly sensitive scanning tunneling microscope (STM) to manipulate atoms on a specially engineered magnetic surface.
Strain can unlock electron-donating orbital in tetravalent carbon atoms
Scheiner and Zierkiewicz, however, have been studying apical carbon atoms in propellane and pyramidane molecules, where the bonding situation is rather different. Along with Mariusz Michalczyk, also at Wrocław University of Science and Technology, they’ve identified an electron-donating orbital – or pseudo lone pair – on these tetrahedral carbons.
While it clearly has a negative charge, Scheiner acknowledges that the nature of this electron-donating orbital could be up for debate. Nonetheless, it appears that this region of negative electrostatic potential can attract the σ-hole of an electrophile to form various non-covalent interactions including hydrogen, halogen, chalcogen, pnictogen and tetrel bonds.
The Empty Atom Myth: Why “Nothing” Isn’t Empty at All
Go to https://groundnews.com/physics to stay fully informed about physics, other sciences, and more. Subscribe through my link to get 40% off the unlimited vantage plan, the same one I use, which breaks down to just $5/month with my discount.
You can help support this channel via the Physics Explained Patreon account: / physicsexplained.
We’ve all heard the claim: atoms are mostly empty space. That if you zoomed in far enough, you’d find 99.9999999999999% of an atom is just… nothing. But this idea, while popular, is deeply misleading.
In this video, we dive into the quantum reality behind that empty space — and reveal what truly fills the “void” inside atoms. From the discovery of the nucleus to the rise of quantum field theory, we’ll explore how jittering fields, zero-point energy, and vacuum fluctuations reshape our understanding of what “nothing” really is.
Along the way, you’ll learn:
Why Rutherford’s model gave birth to the “empty atom” idea.
Precision Spectroscopy Reaffirms Gap Between Theory and Experiment
New physics may explain discrepant values for the ionization energy of a metastable state of helium.
In the search for new physics beyond the standard model of particle physics, a significant discrepancy between theory and experiment attracts attention, especially in a simple atomic system such as helium. Recently, evidence has appeared for a 9 discrepancy in the ionization energy of the metastable triplet state of helium-4 (4He) [1, 2]. This stands out like a sore thumb in a field where theory and experiment are both highly accurate and normally in agreement. However, in assessing the validity of the discrepancy, there is always the possibility that something has been overlooked or miscalculated. Now Gloria Clausen and Frédéric Merkt of the Swiss Federal Institute of Technology (ETH) Zurich have released the results of their latest research [3] in a series of high-precision experiments [1, 4]. Their results (Fig.
Memory matters for quantum atomic motion on metals
In a variety of technological applications related to chemical energy generation and storage, atoms and molecules diffuse and react on metallic surfaces. Being able to simulate and predict this motion is crucial to understanding material degradation, chemical selectivity, and to optimizing the conditions of catalytic reactions. Central to this is a correct description of the constituent parts of atoms: electrons and nuclei.
An electron is incredibly light—its mass is almost 2,000 times smaller than that of even the lightest nucleus. This mass disparity allows electrons to adapt rapidly to changes in nuclear positions, which usually enables researchers to use a simplified “adiabatic” description of atomic motion.
While this can be an excellent approximation, in some cases the electrons are affected by nuclear motion to such an extent that we need to abandon this simplification and account for the coupling between the dynamics of electrons and nuclei, leading to so-called “non-adiabatic effects.”
Decades-long experiment finds muon still behaving unexpectedly
Final results from a long-running U.S.-based experiment announced Tuesday show a tiny particle continues to act strangely—but that’s still good news for the laws of physics as we know them.
“This experiment is a huge feat in precision,” said Tova Holmes, an experimental physicist at the University of Tennessee, Knoxville who is not part of the collaboration.
The mysterious particles called muons are considered heavier cousins to electrons. They wobble like a top when inside a magnetic field, and scientists are studying that motion to see if it lines up with the foundational rulebook of physics called the Standard Model.
Researchers unveil axion-torsion coupling via dark photons
A new study has revealed a novel effect caused by dark photons—hypothetical particles thought to make up a portion of the universe’s elusive dark matter. This discovery, made within the framework of Einstein–Cartan–Holst gravity, provides new insights into the fundamental interactions between matter and gravity.
The study was conducted by Prof. Gao Zhifu from the Xinjiang Astronomical Observatory of the Chinese Academy of Sciences, in collaboration with Dr. Luiz Carlos Garcia de Andrade from the State University of Rio de Janeiro, Brazil. Their findings, which include the first identification of a key physical quantity known as the Barbero–Immirzi (BI) parameter induced by dark photons, are published in The European Physical Journal C.
A large portion of the universe is filled with invisible matter known as dark matter, and the dark photon is one of its leading theoretical candidates. As a hypothetical particle beyond the Standard Model, the dark photon exhibits electromagnetic-like interactions through kinetic mixing with the ordinary photon. Unlike photons, however, dark photons possess mass and interact much more weakly with charged particles.