The majority of the matter in our Universe isn’t made of any of the particles in the Standard Model. Could the axion save the day?
Category: particle physics – Page 211
Physicists track how continuous changes in dimensionality affect collective properties of a superfluid
An international research team from Innsbruck and Geneva has, for the first time, probed the dimensional crossover for ultracold quantum matter. In the regime between one and two dimensions, the quantum particles perceive their world as being 1D or 2D depending on the length scale on which they are probed: For short distances, their world is 1D, but it is 2D for long distances.
ATLAS provides first measurement of the W-boson width at the LHC
The discovery of the Higgs boson in 2012 slotted in the final missing piece of the Standard Model puzzle. Yet, it left lingering questions. What lies beyond this framework? Where are the new phenomena that would solve the universe’s remaining mysteries, such as the nature of dark matter and the origin of matter-antimatter asymmetry?
Research Lights up Process for Turning CO₂ into Sustainable Fuel
Researchers have successfully transformed CO2 into methanol by shining sunlight on single atoms of copper deposited on a light-activated material, a discovery that paves the way for creating new green fuels.
An international team of researchers from the University of Nottingham’s School of Chemistry, University of Birmingham, University of Queensland, and University of Ulm have designed a material made up of copper anchored on nanocrystalline carbon nitride.
The copper atoms are nested within the nanocrystalline structure, which allows electrons to move from carbon nitride to CO2, an essential step in the production of methanol from CO2 under the influence of solar irradiation. The research has been published in the Sustainable Energy & Fuels journal.
Black Hole Effects on Quantum Information Discovered in Everyday Chemistry
Nothing makes a mess of quantum physics quite like those space-warping, matter-gulping abominations known as black holes. If you want to turn Schrodinger’s eggs into an information omelet, just find an event horizon and let ‘em drop.
According to theoretical physicists and chemists from Rice University and the University of Illinois Urbana-Champaign in the US, basic chemistry is capable of scrambling quantum information almost as effectively.
The team used a mathematical tool developed more than half a century ago to bridge a gap between known semiclassical physics and quantum effects in superconductivity. They found the delicate quantum states of reacting particles become scrambled with surprising speed and efficiency that comes close to matching the might of a black hole.
Broken Symmetries and the Masses of Gauge Bosons
“Nobody else took what I was doing seriously, so nobody would want to work with me. I was thought to be a bit eccentric and maybe cranky”
- Peter Higgs, 29 May 1929 – 8 April 2024.
Image from: Fermat’s Library.
https://en.wikipedia.org/wiki/Peter_Higgs
Phys. Rev. Lett. 13,508 – Published 19 October 1964.
Breakthrough achieves electrically controlled polaritons at room temperature
A research team consisting of Professor Kyoung-Duck Park and Hyeongwoo Lee, an integrated PhD student, from the Department of Physics at Pohang University of Science and Technology (POSTECH) has pioneered an innovative technique in ultra-high-resolution spectroscopy. Their breakthrough marks the world’s first instance of electrically controlling polaritons – hybridized light-matter particles – at room temperature.
This research has been published in Physical Review Letters (“Electrically Tunable Single Polaritonic Quantum Dot at Room Temperature”).
Image depicting the control of polariton particles using electric-field tip-enhanced strong coupling spectroscopy. (Image: POSTECH)
CMS experiment at CERN measures a key parameter of the Standard Model
Last week, at the annual Rencontres de Moriond conference, the CMS collaboration presented a measurement of the effective leptonic electroweak mixing angle. The result is the most precise measurement performed at a hadron collider to date and is in good agreement with the prediction from the Standard Model.
The Standard Model of particle physics is the most precise description to date of particles and their interactions. Precise measurements of its parameters, combined with precise theoretical calculations, yield spectacular predictive power that allows phenomena to be determined even before they are directly observed.
In this way, the model successfully constrained the masses of the W and Z bosons (discovered at CERN in 1983), of the top quark (discovered at Fermilab in 1995) and, most recently, of the Higgs boson (discovered at CERN in 2012). Once these particles had been discovered, these predictions became consistency checks for the model, allowing physicists to explore the limits of the theory’s validity.