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Archive for the ‘particle physics’ category: Page 274

Jan 30, 2022

How Mathematical ‘Hocus-Pocus’ Saved Particle Physics

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

“It is what I would call a dippy process,” Richard Feynman later wrote. “Having to resort to such hocus-pocus has prevented us from proving that the theory of quantum electrodynamics is mathematically self-consistent.”

Justification came decades later from a seemingly unrelated branch of physics. Researchers studying magnetization discovered that renormalization wasn’t about infinities at all. Instead, it spoke to the universe’s separation into kingdoms of independent sizes, a perspective that guides many corners of physics today.

Renormalization, writes David Tong, a theorist at the University of Cambridge, is “arguably the single most important advance in theoretical physics in the past 50 years.”

Jan 30, 2022

Massless particles can’t be stopped

Posted by in categories: cosmology, particle physics

If a particle has no mass, how can it exist?

Scientists think that, under some circumstances, dark matter could generate powerful enough gravitational waves for equipment like LIGO to detect.

Four physicists share their journeys through academia into industry and offer words of wisdom for those considering making a similar move.

Jan 28, 2022

Burn, baby, burn: Nuclear scientists achieve major fusion feat

Posted by in categories: nuclear energy, particle physics

The ultimate goal, still years away, is to generate power the way the sun generates heat, by smooshing hydrogen atoms so close to each other that they combine into helium, which releases torrents of energy.

WATCH: Is alluring but elusive fusion energy possible in our lifetime?

A team of more than 100 scientists published the results of four experiments that achieved what is known as a burning plasma in Wednesday’s journal Nature. With those results, along with preliminary results announced last August from follow-up experiments, scientists say they are on the threshold of an even bigger advance: ignition. That’s when the fuel can continue to “burn” on its own and produce more energy than what’s needed to spark the initial reaction.

Jan 28, 2022

Simulations show iron catalyzes corrosion in ‘inert’ carbon dioxide

Posted by in categories: materials, particle physics

Iron that rusts in water theoretically shouldn’t corrode in contact with an “inert” supercritical fluid of carbon dioxide. But it does.

The reason has eluded to now, but a team at Rice University has a theory that could contribute to new strategies to protect iron from the environment.

Materials theorist Boris Yakobson and his colleagues at Rice’s George R. Brown School of Engineering found through atom-level simulations that iron itself plays a role in its own corrosion when exposed to supercritical CO2 (sCO2) and trace amounts of water by promoting the formation of reactive species in the fluid that come back to attack it.

Jan 28, 2022

Finally, an Explanation for the Cold Spot in the Cosmic Microwave Background

Posted by in categories: cosmology, particle physics

According to our current Cosmological models, the Universe began with a Big Bang roughly 13.8 billion years ago. During the earliest periods, the Universe was permeated by an opaque cloud of hot plasma, preventing atoms from forming. About 380,000 years later, the Universe cooled to a temperature of about-270 °C (−454 °F), which converted much of the energy generated by the Big Bang into light. This afterglow is now visible to astronomers as the Cosmic Microwave Background (CMB), first observed during the 1960s.

One peculiar characteristic about the CMB that attracted a lot of attention was the tiny fluctuations in temperature, which could provide information about the early Universe. In particular, there is a rather large spot in the CMB that is cooler than the surrounding afterglow, known as the CMB Cold Spot. After decades of studying the CMB’s temperature fluctuations, a team of scientists recently confirmed the existence of the largest cold spots in the CMB afterglow – the Eridanus Supervoid – might be the explanation for the CMB Cold Spot that astronomers have been looking for!

Continue reading “Finally, an Explanation for the Cold Spot in the Cosmic Microwave Background” »

Jan 28, 2022

Physicist’s Radical Solution to Century Old Problem of Radiation Reaction — With Controversial Implications

Posted by in categories: mathematics, particle physics

A Lancaster physicist has proposed a radical solution to the question of how a charged particle, such as an electron, responded to its own electromagnetic field.

This question has challenged physicists for over 100 years but mathematical physicist Dr. Jonathan Gratus has suggested an alternative approach — published in the Journal of Physics A — with controversial implications.

It is well established that if a point charge accelerates it produces electromagnetic radiation. This radiation has both energy and momentum, which must come from somewhere. It is usually assumed that they come from the energy and momentum of the charged particle, damping the motion.

Jan 27, 2022

What lies beyond the Standard Model?

Posted by in categories: cosmology, particle physics

Physicists must swing between crafting the mind-bending ideas about reality that make up theories and advancing technologies to the point where new experiments can test those theories. 2021 was a big year for advancing the experimental tools of physics.

First, the world’s largest particle accelerator, the Large Hadron Collider at CERN, was shut down and underwent some substantial upgrades. Physicists just restarted the facility in October, and they plan to begin the next data collection run in May 2022. The upgrades have boosted the power of the collider so that it can produce collisions at 14 TeV, up from the previous limit of 13 TeV. This means the batches of tiny protons that travel in beams around the circular accelerator together carry the same amount of energy as an 800,000-pound (360,000-kilogram) passenger train traveling at 100 mph (160 kph). At these incredible energies, physicists may discover new particles that were too heavy to see at lower energies.

Some other technological advancements were made to help the search for dark matter. Many astrophysicists believe that dark matter particles, which don’t currently fit into the Standard Model, could answer some outstanding questions regarding the way gravity bends around stars – called gravitational lensing – as well as the speed at which stars rotate in spiral galaxies. Projects like the Cryogenic Dark Matter Search have yet to find dark matter particles, but the teams are developing larger and more sensitive detectors to be deployed in the near future.

Jan 27, 2022

Scientists Link Genes to Longer Human Lifespan

Posted by in categories: particle physics, quantum physics

A group of genes that play an essential role in building components of our cells can also impact human lifespan, finds a new study led by UCL researchers. The genes have previously been found to extend lifespan in small organisms, such as making fruit flies live 10% longer, but this is the first.


MIT physicists have discovered a new quantum bit, or “qubit,” in the form of vibrating pairs of atoms known as fermions. They found that when pairs of fermions are chilled and trapped in an optical lattice, the particles can exist simultaneously in two states—a weird quantum phenomenon known as superposition. In this case, the atoms held a superposition of two vibrational states, in which the pair wobbled against each other while also swinging in sync, at the same time.

Jan 26, 2022

‘X particle’ from the dawn of time detected inside the Large Hadron Collider

Posted by in category: particle physics

The particle was found by smashing billions of lead atoms into each other at extreme speeds.

Jan 26, 2022

How the Physics of Resonance Shapes Reality

Posted by in categories: mathematics, media & arts, particle physics

Almost anytime physicists announce that they’ve discovered a new particle, whether it’s the Higgs boson or the recently bagged double-charm tetraquark, what they’ve actually spotted is a small bump rising from an otherwise smooth curve on a plot. Such a bump is the unmistakable signature of “resonance,” one of the most ubiquitous phenomena in nature.

Resonance underlies aspects of the world as diverse as music, nuclear fusion in dying stars, and even the very existence of subatomic particles. Here’s how the same effect manifests in such varied settings, from everyday life down to the smallest scales.

In its simplest form, resonance occurs when an object experiences an oscillating force that’s close to one of its “natural” frequencies, at which it easily oscillates. That objects have natural frequencies “is one of the bedrock properties of both math and the universe,” said Matt Strassler, a particle physicist affiliated with Harvard University who is writing a book about the Higgs boson. A playground swing is one familiar example: “Knock something like that around, and it will always pick out its resonant frequency automatically,” Strassler said. Or flick a wineglass and the rim will vibrate a few hundred times per second, producing a characteristic tone as the vibrations transfer to the surrounding air.