Archive for the ‘particle physics’ category: Page 363

Nov 23, 2018

Meet Dawn Shaughnessy, the Real-Life Alchemist Who Expanded the Periodic Table

Posted by in categories: chemistry, particle physics

The periodic table is chemistry’s holy text. Not only does it list all of the tools at chemists’ disposal, but its mere shape—where these elements fall into specific rows and columns—has made profound predictions about new elements and their properties that later came true. But few chemists on Earth have a closer relationship with the document than Dawn Shaughnessy, whose team is partially responsible for adding six new elements to table’s ranks.

Shaughnessy leads a team of real-life alchemists. You might be familiar with alchemy as a medieval European practice where mystics attempted to transmute elements into more valuable ones. But rather than turn the element lead into gold, Shaughnessy and her team turned plutonium into flerovium.

Shaughnessy’s parents encouraged her to pursue science from a young age—her father was an engineer, and she had an electronics kit as well as a chemistry set as a child. She’d first thought about doing orthopedic research but didn’t want to cut people open, she explained to me, and chemistry was a natural fit. But when she arrived at the University of California, Berkeley as an undergraduate, she learned that chemistry could be more than just mixing liquids in beakers. She could create the atoms themselves.

Continue reading “Meet Dawn Shaughnessy, the Real-Life Alchemist Who Expanded the Periodic Table” »

Nov 21, 2018

The microscope revolution that’s sweeping through materials science

Posted by in categories: particle physics, science

Scientists can’t study what they can’t measure — as David Muller knows only too well. An applied physicist, Muller has been grappling for years with the limitations of the best imaging tools available as he seeks to probe materials at the atomic scale.

One particularly vexing quarry has been ultra-thin layers of the material molybdenum disulfide, which show promise for building thin, flexible electronics. Muller and his colleagues at Cornell University in Ithaca, New York, have spent years peering at MoS2 samples under an electron microscope to discern their atomic structures. The problem was seeing the sulfur atoms clearly, Muller says. Raising the energy of the electron beam would sharpen the image, but knock atoms out of the MoS2 sheet in the process. Anyone hoping to say something definitive about defects in the structure would have to guess. “It would take a lot of courage, and maybe half the time, you’d be right,” he says.

This July, Muller’s team reported a breakthrough. Using an ultra-sensitive detector that the researchers had created and a special method for reconstructing the data, they resolved features in MoS2 down to 0.39 angstroms, two and a half times better than a conventional electron microscope would achieve. (1 Å is one-tenth of a nanometre, and a common measure of atomic bond lengths.) At once, formerly fuzzy sulfur atoms now showed up clearly — and so did ‘holes’ where they were absent. Ordinary electron microscopy is “like flying propeller planes”, Muller says. “Now we have a jet.”

Continue reading “The microscope revolution that’s sweeping through materials science” »

Nov 20, 2018

A Universal Quantum Phenomenon in Strange Metals

Posted by in categories: particle physics, quantum physics

A ubiquitous quantum phenomenon has been detected in a large class of superconducting materials, fueling a growing belief among physicists that an unknown organizing principle governs the collective behavior of particles and determines how they spread energy and information.

Read more

Nov 19, 2018

Scientists Just Proved A Fundamental Quantum Physics Problem is Unsolvable

Posted by in categories: particle physics, quantum physics

Scientists have proven for the very first time that one of the most fundamental problems of particle and quantum physics is mathematically unsolvable.

In short, they show that regardless of how no matter how perfectly we can mathematically describe a material on the microscopic level, we are never going to be able to predict its macroscopic behavior. Never.

The work was published in Nature.

Read more

Nov 18, 2018

What is String Theory And Why Humanity Absolutely Needs It

Posted by in categories: particle physics, quantum physics

String theory is a complex theory that describes our reality with superstrings as the most basic and fundamental piece of all matter Theoretical particle physicist Daniele Amati supposedly said that string theory was 21st century physics that fell by chance into the 20th century.

Read more

Nov 17, 2018

A new lead on a 50-year-old radiation damage mystery

Posted by in categories: nuclear energy, particle physics

For half a century, researchers have seen loops of displaced atoms appearing inside nuclear reactor steel after exposure to radiation, but no one could work out how.

Read more

Nov 17, 2018

Infinite-dimensional symmetry opens up possibility of a new physics—and new particles

Posted by in category: particle physics

The symmetries that govern the world of elementary particles at the most elementary level could be radically different from what has so far been thought. This surprising conclusion emerges from new work published by theoreticians from Warsaw and Potsdam. The scheme they posit unifies all the forces of nature in a way that is consistent with existing observations and anticipates the existence of new particles with unusual properties that may even be present in our close environs.

Read more

Nov 17, 2018

What is absolute zero?

Posted by in categories: particle physics, space

The coldest place beyond Earth is artificial, too. Last summer, astronauts activated an experiment called the Cold Atom Lab aboard the International Space Station. The lab has attained temperatures 30 million times lower than empty space. “I’ve been working on this idea, off and on, for over 20 years,” says Robert Thompson of NASA’s Jet Propulsion Lab, one of the researchers who devised the experiment. “It feels incredible to witness it up and operating.”

What happens when matter gets that cold?

If Thompson sounds excited, it’s because ultra-cold atoms behave in fascinating and potentially useful ways. For one thing, they lose their individual identities, fusing to form a bizarre state of matter called a Bose-Einstein condensate.

Read more

Nov 16, 2018

Metallic nanoparticles light up another path towards eco-friendly catalysts

Posted by in categories: nanotechnology, particle physics

Scientists at Tokyo Institute of Technology produced subnano-sized metallic particles that are as much as 50 times more effective than well-known Au-Pd bimetallic nanocatalysts.

Read more

Nov 16, 2018

Spacecraft Witness Explosion in Earth’s Magnetic Field

Posted by in categories: particle physics, satellites

Magnetic fields around the Earth release strong bursts of energy, accelerating particles and feeding the auroras that glow in the polar skies. On July 11, 2017, four NASA spacecrafts were there to watch one of these explosions happen.

The process that produces these bursts is called magnetic reconnection, in which different plasmas and their associated magnetic fields interact, releasing energy. The Magnetospehric Multiscale Mission (MMS) satellites launched in 2015 to study the places where this reconnection process occurs. This newly released research shows for the first time that the mission encountered one of these reconnection sites in the night side of the Earth’s magnetic field, which extends behind the planet as a long “magnetotail.”

Read more