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Archive for the ‘particle physics’ category: Page 194

Mar 11, 2022

Stronger and Faster Than Lightning: Scientists Achieve Rare Quantum State in Polycrystals

Posted by in categories: chemistry, climatology, particle physics, quantum physics

Scientists from the Max Planck Institute for Polymer Research, Paderborn University, and the University of Konstanz have succeeded in achieving a rare quantum state. They are the first to have demonstrated Wannier-Stark localization in a polycrystalline substance. Predicted around 80 years ago, the effect has only recently been proven — in a monocrystal. Until now, researchers assumed this localization to be possible only in such monocrystalline substances which are very complicated to produce. The new findings represent a breakthrough in the field of physics and could in future give rise to new optical modulators, for example, that can be used in information technologies based on light, among other things. The physicists have published their findings in the well-respected technical journal, Nature Communications.

Stronger and faster than lightning

The atoms of a crystal are arranged in a three-dimensional grid, held together by chemical bonds. These bonds can, however, be dissolved by very strong electric fields which displace atoms, even going so far as to introduce so much energy into the crystal that it is destroyed. This is what happens when lightning strikes and materials liquefy, vaporize or combust, for example. To demonstrate Wannier-Stark localization, the scientists’ experiments involved setting up electric fields of several million volts per centimeter, much stronger than the fields involved in lightning strikes. During this process, the electronic system of a solid — in this case, a polycrystal — is forced far from a state of equilibrium for a very short time. Wannier-Stark localization involves virtually shutting down some of the chemical bonds temporarily. This state can only be maintained for less than a picosecond — one millionth of one millionth of a second — without destroying the substance.

Mar 7, 2022

Astronomers See an Enormous Shockwave — 60x Bigger Than the Entire Milky Way Galaxy

Posted by in categories: cosmology, particle physics

Astronomers have a thing for big explosions and collisions, and it always seems like they are trying to one-up themselves in finding a bigger, brighter one. There’s a new entrant to that category – an event so big it created a burst of particles over 1 billion years ago that is still visible today and is 60 times bigger than the entire Milky Way.

That shockwave was created by the merger of two galaxy clusters to create a supercluster known as Abell 3667. This was one of the most energetic events in the universe since the Big Bang 0, according to calculations by Professor Francesco de Gasperin and his time from the University of Hamburg and INAF. When it happened over 1 billion years ago, it shot out a wave of electrons, similar to how a particle accelerator would. All these years later, those particles are still traveling at Mach 2.5 (1500 km/s), and when they pass through magnetic fields, they emit radio waves.

Mar 7, 2022

Local nuclear reactor helps scientists catch and study neutrinos

Posted by in categories: nuclear energy, particle physics

A nuclear reactor at an Illinois energy plant is helping University of Chicago scientists learn how to catch and understand the tiny, elusive particles known as neutrinos.

At Constellation’s (formerly Exelon) Dresden Generating Station in Morris, Illinois, the team took the first measurements of coming off a with a tiny detector. These particles are extremely hard to catch because they interact so rarely with matter, but power reactors are one of the few places on Earth with a high concentration of them.

“This was an exciting opportunity to benefit from the enormous neutrino production from a reactor, but also a challenge in the noisy industrial environment right next to a reactor,” said Prof. Juan Collar, a particle physicist who led the research. “This is the closest that neutrino physicists have been able to get to a commercial reactor core. We gained unique experience in operating a detector under these conditions, thanks to Constellation’s generosity in accommodating our experiment.”

Mar 5, 2022

PLAN A: Our team developed a simulation for a plausible escalating war between the United States and Russia using realistic nuclear force postures, targets and fatality estimates

Posted by in category: particle physics

It is estimated that there would be more than 90 million people dead and injured within the first few hours of the conflict.

For more, see https://sgs.princeton.edu/the-lab/plan-a.

Continue reading “PLAN A: Our team developed a simulation for a plausible escalating war between the United States and Russia using realistic nuclear force postures, targets and fatality estimates” »

Mar 5, 2022

The Large Hadron Collider will explore the cutting edge of physics after 3-year shutdown

Posted by in category: particle physics

Scientists are gearing up to once more push the boundaries of the cutting edge of particle physics with the reopening of the Large Hadron Collider (LHC) at CERN after a three-year shutdown.

Mar 4, 2022

World’s Smallest Droplets Created In World’s Largest Atom Smasher

Posted by in category: particle physics

Circa 2013


A team of physicists at a university in the Netherlands have 3D-printed a microscopic version of the USS Voyager, an Intrepid-class starship from Star Trek.

Mar 3, 2022

Physics: Speed of Light Could Be Dropped to Zero Using Crystals

Posted by in categories: mathematics, particle physics

In a vacuum like space, the speed of light is just over 186,280 miles per second. Scientists have now shown it’s possible to slow it down to zero miles per second without sacrificing its brightness, regardless of its frequency or bandwidth.

A team of researchers from the Israel Institute of Technology and the Institute of Pure and Applied Mathematics in Brazil discovered a method of theoretically bringing the speed of light to a halt by capitalizing on “exceptional points”—coordinates at which two separate light emissions reach each other and merge into a single one, according to Phys.org. A paper describing the research was published in the scientific journal Physical Review Letters.

Continue reading “Physics: Speed of Light Could Be Dropped to Zero Using Crystals” »

Mar 3, 2022

Catalyst turns carbon dioxide into gasoline 1,000 times more efficiently

Posted by in categories: chemistry, engineering, particle physics

Engineers working to reverse the proliferation of greenhouse gases know that in addition to reducing carbon dioxide emissions we will also need to remove carbon dioxide from power plant fumes or from the skies. But, what do we do with all that captured carbon? Matteo Cargnello, a chemical engineer at Stanford University, is working to turn it into other useful chemicals, such as propane, butane or other hydrocarbon fuels that are made up of long chains of carbon and hydrogen.

“We can create gasoline, basically,” said Cargnello, who is an assistant professor of chemical engineering. “To capture as much as possible, you want the longest chain hydrocarbons. Chains with eight to 12 would be the ideal.”

A new catalyst, invented by Cargnello and colleagues, moves toward this goal by increasing the production of long-chain hydrocarbons in chemical reactions. It produced 1,000 times more butane—the longest hydrocarbon it could produce under its maximum pressure—than the standard catalyst given the same amounts of carbon , hydrogen, catalyst, pressure, heat and time. The new catalyst is composed of the element ruthenium—a rare transition metal belonging to the platinum group—coated in a thin layer of plastic. Like any catalyst, this invention speeds up chemical reactions without getting used up in the process. Ruthenium also has the advantage of being less expensive than other high-quality catalysts, like palladium and platinum.

Mar 3, 2022

Study reveals chemical link between wildfire smoke and ozone depletion

Posted by in categories: chemistry, particle physics

The Australian wildfires in 2019 and 2020 were historic for how far and fast they spread, and for how long and powerfully they burned. All told, the devastating “Black Summer” fires blazed across more than 43 million acres of land, and extinguished or displaced nearly 3 billion animals. The fires also injected over 1 million tons of smoke particles into the atmosphere, reaching up to 35 kilometers above Earth’s surface — a mass and reach comparable to that of an erupting volcano.

Now, atmospheric chemists at MIT have found that the smoke from those fires set off chemical reactions in the stratosphere that contributed to the destruction of ozone, which shields the Earth from incoming ultraviolet radiation. The team’s study, appearing this week in the Proceedings of the National Academy of Sciences, is the first to establish a chemical link between wildfire smoke and ozone depletion.

In March 2020, shortly after the fires subsided, the team observed a sharp drop in nitrogen dioxide in the stratosphere, which is the first step in a chemical cascade that is known to end in ozone depletion. The researchers found that this drop in nitrogen dioxide directly correlates with the amount of smoke that the fires released into the stratosphere. They estimate that this smoke-induced chemistry depleted the column of ozone by 1 percent.

Mar 2, 2022

Quantum Friction Explains Water’s Freaky Flow

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

Schran agrees. “This new mechanism of friction is definitely very interesting and exciting,” he says. “But what is missing in my opinion, is a clear benchmark measurement.” Quantifying, for instance, how friction changes based on water’s interaction with single versus multiple layers of carbon atoms could go a long way to fully verifying the new theory, which predicts that greater numbers of electrons in the multilayered carbon will boost friction.

The study team is already progressing along this path and dreaming of what lies beyond. They are hoping to eventually test their theory with flowing liquids other than water, and nanotubes composed of elements besides carbon. In such cases, molecules in the liquid and the electrons within nanotube walls would follow different patterns of interaction, possibly leading to changes in the degree of quantum friction. Lydéric Bocquet says that it may even be possible to control the amount of friction a flowing liquid experiences by constructing nanotubes with electron behavior explicitly in mind.

The new study sets the stage for years of complex exploration by experimental and theoretical physicists alike and, according to Kavokine, also signals a fundamental shift in how physicists should think about friction. “Physicists have long thought that it is different at the nanoscale, but this difference was not so obvious to find and describe,” he says. “They were dreaming about some quantum behavior arising at these scales—and now we have shown how it does.”