New data is evidence of process that powers exploding stars

image of a multicolored blob.

Enlarge / A multi-wavelength image of the Cassiopeia A supernova remnant. (credit: Courtesy NASA/JPL-Caltech)

Supernovae happen. We’ve witnessed enough of them that we’re pretty sure of that. Why they happen has been another issue entirely. As we’ve worked on understanding the physics that drives these immense explosions, we’ve occasionally gone through awkward periods when the stars in our models stop exploding. Adding in more realistic physics has generally gotten the models booming again, and right now we’re in a period where the latest models appear to be happily self-destructing.

The challenge is trying to find evidence that the physics we’re using in our successful models accurately reflects what’s going on in a dying star—not an easy task with an event that instantly destroys much of the evidence.

Now, data from the Chandra X-ray Observatory provides a hint that a mechanism used in recent supernova models is probably right. The results are published in this week’s issue of Nature.

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#astrophysics, #isotopes, #physics, #science, #supernova

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Cracking the case: New study sheds more light on the “Brazil nut effect”

(video link)

Open a can of mixed nuts, and chances are you’ll find a bunch of Brazil nuts topping the heap—whether that’s a good or bad thing depends on how you feel about Brazil nuts. It’s such a common phenomenon that it’s known as the “Brazil nut effect” (though muesli mix also gives rise to the same dynamics of granular convection). Now, on video for the first time, a team of scientists from the University of Manchester in England has captured the complicated dynamics that cause the Brazil nut effect, according to a new paper published in the journal Scientific Reports.

From a physics standpoint, those mixed nuts are an example of a granular material, like a sand pile. As I wrote at Gizmodo back in 2016, the primary mechanisms behind the Brazil nut effect are percolation and convection. Percolation causes smaller grains to move through larger grains to the bottom of the pile, while convection pushes the larger grains toward the top. Complicating matters is gravity, pulling down on every grain, as well as the fact that every individual grain is jostling against all the others in the container, producing friction and mechanical energy (lost as heat).

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#brazil-nut-effect, #granular-convection, #granular-materials, #physics, #science, #x-ray-computed-tomography

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Quantum Astronomy Could Create Telescopes Hundreds of Kilometers Wide

Astronomers hope to use innovations from the subatomic world to construct breathtakingly large arrays of optical observatories

— Read more on ScientificAmerican.com

#physics, #space, #the-sciences

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Fermilab’s latest muon measurements hint at cracks in the Standard Model

The Muon g-2 particle storage ring, now housed at Fermilab.

Enlarge / The Muon g-2 particle storage ring, now housed at Fermilab. (credit: Cindy Arnold/Fermilab)

The Muon g-2 experiment (pronounced “gee minus two”) is designed to look for tantalizing hints of physics beyond the Standard Model of particle physics. It does this by measuring the magnetic field (aka the magnetic moment) generated by a subatomic particle known as the muon. Back in 2001, an earlier run of the experiment at Brookhaven National Laboratory found a slight discrepancy, hinting at possible new physics, but that controversial result fell short of the critical threshold required to claim discovery.

Now, Fermilab physicists have completed their initial analysis of data from the updated Muon g-2 experiment, showing “excellent agreement” with the discrepancy Brookhaven recorded. The results were announced today in a new paper published in the journal Physical Review Letters.

As I wrote at Nautilus in 2013, before the muon was first discovered in 1936, physicists thought their model of particle physics was pretty much complete. Then Caltech physicists Carl Anderson and Seth Neddermeyer, who were studying cosmic rays, noticed that some particles didn’t curve as expected when they passed through a magnetic field. A year later, cloud chamber experiments confirmed that these particles were, indeed, new. It was such a surprising development that I.I. Rabi famously declared, “Who ordered that?”

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#fermilab, #mighty-muons, #muon-g-2, #muons, #physics, #science

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Is the Standard Model of Physics Now Broken?

The discrepancy between the theoretical prediction and the experimentally determined value of the muon’s magnetic moment has become slightly stronger with a new result from Fermilab. But what does it…

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Honeywell releases details of its ion trap quantum computer

Image of a small electronic device.

Enlarge / The line down the middle is where the trapped ions reside. (credit: Honeywell)

About a year ago, Honeywell announced that it had entered the quantum computing race with a technology that was different from anything else on the market. The company claimed that because the performance of its qubits was so superior to those of its competitors, its computer could do better on a key quantum computing benchmark than quantum computers with far more qubits.

Now, roughly a year later, the company finally released a paper describing the feat in detail. But in the meantime, the competitive landscape has shifted considerably.

It’s a trap!

In contrast to companies like IBM and Google, Honeywell has decided against using superconducting circuitry and in favor of using a technology called “trapped ions.” In general, these use a single ion as a qubit and manipulate its state using lasers. There are different ways to create ion trap computers, however, and Honeywell’s version is distinct from another on the market, made by a competitor called IonQ (which we’ll come back to).

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#computer-science, #honeywell, #ion-trap, #physics, #quantum-computing, #quantum-mechanics, #science

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Big Physics News: The Muon g-2 Experiment, Explained

Particles called muons are behaving weirdly and it could mean a huge discovery

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Finding From Particle Research Could Break Known Laws of Physics

It’s not the next Higgs boson — yet. But the best explanation, physicists say, involves forms of matter and energy not currently known to science.

#brookhaven-ny, #brookhaven-national-laboratory, #chicago-ill, #fermi-national-accelerator-laboratory, #higgs-boson, #illinois, #large-hadron-collider, #muon-subatomic-particle, #particle-accelerators, #physics, #space-and-astronomy, #your-feed-science

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Long-Awaited Muon Measurement Boosts Evidence for New Physics

Initial data from the Muon g-2 experiment have excited particle physicists searching for undiscovered subatomic particles and forces

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Physicists give antimatter the chills

Image of coils of copper-colored metal.

Enlarge / One of the magnets used to help contain antimatter. (credit: Brookhaven National Lab)

On Wednesday, scientists reported successfully cooling atoms made of antimatter using an ultraviolet laser. The cooling process deployed here works on normal matter, so it was also expected to work just fine with the antihydrogen used for these experiments. Rather than providing yet another confirmation that matter and antimatter appear to behave the same, the experiment is significant because it increases our chances of being able to identify subtle differences between the two types of matter.

Exotic yet apparently normal

Normal matter and antimatter are notable for their ability to annihilate each other in a burst of energy when they come in contact. But otherwise, our understanding of the physics of antiparticles indicates that they should behave identically—an antiproton can pair with an antielectron to form antihydrogen, which would then be subject to forces like gravity and electromagnetism. As far as most of physics is concerned, antimatter is just matter reflected by a mirror: a few things reversed, but otherwise identical.

Testing that, however, is a challenge. All the antimatter produced naturally on Earth comes from energetic processes like radioactive decays and the impact of cosmic rays. As a result, the antimatter itself carries plenty of energy, and it moves very quickly. Similar things apply to antimatter we humans produce. It’s generally made by colliding energetic particles with a stationary target, and the antimatter that comes out of these collisions is also very energetic.

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#antimatter, #cern, #lasers, #physics, #science

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Long-Awaited Muon Physics Experiment Nears Moment of Truth

A result that has been 20 years in the making could reveal the existence of new particles, and upend fundamental physics

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Hunting Ghost Particles Beneath the World’s Deepest Lake

A neutrino-spotting telescope beneath Russia’s frozen Lake Baikal in Russia is close to delivering scientific results after four decades of setbacks.

#domogatski-grigori-v, #ice, #lake-baikal-russia, #neutrinos, #physics, #research, #russia, #siberia, #space-and-astronomy, #stars-and-galaxies, #telescopes-and-observatories

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Unexplained Results Intrigue Physicists at World’s Largest Particle Collider

Muons and electrons might not experience the same fundamental interactions, contrary to Standard Model predictions

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Event Horizon Telescope captures new view of black hole in polarized light

Two years ago, the Event Horizon Telescope (EHT) made headlines with its announcement of the first direct image of a black hole. Science magazine named the image its Breakthrough of the Year. Now the EHT collaboration is back with another groundbreaking result: a new image of the same black hole, this time showing how it looks in polarized light. The ability to measure that polarization for the first time—a signature of magnetic fields at the black hole’s edge—is expected to yield fresh insight into how black holes gobble up matter and emit powerful jets from their cores. The new findings were described in three papers published in The Astrophysical Journal Letters.

“This work is a major milestone: the polarization of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before,” said co-author Iván Martí-Vidal, coordinator of the EHT Polarimetry Working Group and a researcher at the University of Valencia, Spain. “Unveiling this new polarized-light image required years of work due to the complex techniques involved in obtaining and analyzing the data.”

As Ars’ John Timmer reported back in 2019:

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#astronomy, #astrophysics, #black-holes, #event-horizon-telescope, #messier-87, #physics, #science

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Book Review: ‘Life’s Edge,’ by Carl Zimmer

In “Life’s Edge,” Carl Zimmer examines the many scientific attempts to define what it is that exactly constitutes life.

#biology-and-biochemistry, #books-and-literature, #dna-deoxyribonucleic-acid, #lifes-edge-the-search-for-what-it-means-to-be-alive-book, #physics, #science-and-technology, #zimmer-carl

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Ultracold Quantum Collisions Have Been Achieved in Space for the First Time

Creating Bose-Einstein condensates—and crashing them together—in microgravity could lead to physics breakthroughs, better spacecraft navigation and more

— Read more on ScientificAmerican.com

#physics, #space, #the-sciences

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The debate continues: ‘Oumuamua could be remnant of Pluto-like planet

ASU astrophysicists Steven Desch and Alan P. Jackson set out to explain the odd features of ‘Oumuamua and have determined that it is likely a piece of a Pluto-like planet from another solar system.

The mysterious pancake-shaped object dubbed ‘Oumuamua (Hawaiian for “messenger from afar arriving first”) generated considerable controversy earlier this year with the publication of Harvard astronomer Avi Loeb’s bestselling new book arguing that it could be a piece of alien technology. Now two astrophysicists at Arizona State University (ASU) are counterarguing that the secret to at least one aspect of the object’s unusual properties lies in solid nitrogen ice. They described their findings in two new papers published in the Journal of Geophysical Research: Planets.

As we reported previously, in late 2017, our Solar System received its very first known interstellar visitor: a bizarre cigar-shaped object hurtling past at 44 kilometers per second. Scientists have been puzzling over the origin and unusual characteristics of ‘Oumuamua ever since. It was first discovered by the University of Hawaii’s Pan-STARRS1 telescope, part of NASA’s Near-Earth Object Observations program to track asteroids and comets that come into Earth’s vicinity. Other telescopes around the world soon kicked into action, measuring the object’s various characteristics.

Because it had a hyperbolic, or escape, orbit around the Sun, ‘Oumuamua is unlikely to pass our way again. So astronomers only had a brief window of time to gather as much data as they could about the object before it went on its merry way. For starters, ‘Oumuamua was accelerating away from our Sun much faster than could be explained by gravity alone—i.e., via a “rocket effect” that is common in comets, caused by sunlight vaporizing the ice such bodies are made of. While its odd orbit initially had it categorized as a comet, imaging didn’t show any indication of gas and dust being released, as is typical when a comet approaches the Sun. Its elongated, cigar-like shape, combined with its relatively rapid rotation, led to an early suggestion that it could also be an asteroid.

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#oumuamua, #astronomy, #astrophysics, #physics, #science

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Why Does DNA Spontaneously Mutate? Quantum Physics Might Explain

A phenomenon called proton tunneling could account for point mutations in strands of genetic material

— Read more on ScientificAmerican.com

#biology, #physics, #the-sciences

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Sunlight Changes Unequally All Year Long

Some days we gain one minute; some days we gain three

— Read more on ScientificAmerican.com

#earth, #graphic-science, #physics, #space, #the-sciences

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Poem: States of Matter

Science in meter and verse

— Read more on ScientificAmerican.com

#meter, #physics, #the-sciences

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Scientists solve another piece of the puzzling Antikythera mechanism

"Exploded" view of the new computer model of the Antikythera mechanism, showing how it might have worked.

Enlarge / “Exploded” view of the new computer model of the Antikythera mechanism, showing how it might have worked. (credit: Tony Freeth)

Scientists have long struggled to solve the puzzle of the gearing system on the front of the so-called Antikythera mechanism—a fragmentary ancient Greek astronomical calculator, perhaps the earliest example of a geared device. Now, an interdisciplinary team at University College London (UCL) has come up with a computational model that reveals a dazzling display of the ancient Greek cosmos, according to a new paper published in the journal Scientific Reports. The team is currently building a replica mechanism, moving gears and all, using modern machinery. You can watch an extensive 11-minute video about the project here (embedding currently disabled).

“Ours is the first model that conforms to all the physical evidence and matches the descriptions in the scientific inscriptions engraved on the mechanism itself,” said lead author Tony Freeth, a mechanical engineer at UCL. “The Sun, Moon, and planets are displayed in an impressive tour de force of ancient Greek brilliance.”

“We believe that our reconstruction fits all the evidence that scientists have gleaned from the extant remains to date,” co-author Adam Wojcik, a materials scientist at UCL, told the Guardian.

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#antikythera-mechanism, #archaeology, #astronomy, #gaming-culture, #history, #physics, #science

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Ketchup Is Not Just a Condiment: It Is Also a Non-Newtonian Fluid

Everybody’s favorite red sauce may be thin or thick, depending on how it is handled

— Read more on ScientificAmerican.com

#chemistry, #physics, #the-sciences

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Photos of Snowflakes Like You’ve Never Seen Them Before

Whether made with setups using sapphire and carbon fiber or an old mitten and a standard camera, these photographic approaches allow close-ups of the tiny masterpieces formed when snow falls.

#cameras, #komarechka-don, #libbrecht-kenneth-g, #microscopes, #myhrvold-nathan, #photography, #physics, #snow-and-snowstorms, #your-feed-science

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Researchers measure the gravity exerted by a 90 milligram object

Image of two small gold spheres, each on a separate stick.

Enlarge / The experimental setup. (credit: Tobias Westphal / University of Vienna)

Gravity may feel like one of the most familiar forces, but it’s actually among those we understand least. We know our current model of gravity is inconsistent with quantum mechanics. It also fails to account for the phenomena we’ve termed dark matter and dark energy. Unfortunately, studying gravity is extremely challenging because it’s far and away the weakest of the forces. To get around this issue for the detection of gravitational waves, we’ve had to build two immense observatories, far enough apart so that the noise affecting one wouldn’t be picked up at the other.

The gravitational waves we’ve detected come from utterly massive objects like neutron stars and black holes. Now, researchers in Vienna have announced progress toward detecting the gravitational force generated by tiny objects—in this case, spheres of gold only two millimeters across and weighing less than a tenth of a gram. Their work provides the first measurement of gravity at these scales, and the researchers are pretty sure they can go smaller.

It’s so noisy

The work in question involves a fairly typical device for these sorts of experiments. It involves a solid bar with a gold ball attached to each end. The bar is suspended at its center point, which allows it to rotate freely around the horizontal plane. There’s also a mirror placed at its center point, which is used to reflect a laser.

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#gravity, #physics, #science

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Physicists Measure the Gravitational Force between the Smallest Masses Yet

A laboratory experiment captured the pull between two minuscule gold spheres, paving the way for experiments that probe the quantum nature of gravity

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Quantum Mechanics, the Chinese Room Experiment and the Limits of Understanding

All of us, even physicists, often process information without really knowing what we’re doing

— Read more on ScientificAmerican.com

#physics, #the-sciences

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The Latest Wrinkle in Crumple Theory

From studies of “geometric frustration,” scientists learn how paper folds under pressure.

#massachusetts-institute-of-technology, #mathematics, #meteors-and-meteorites, #nature-communications-journal, #origami, #physics, #your-feed-science

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Meet Maxwell’s gambling demon—smart enough to quit while it’s ahead

In a new version of the classic 19th century thought experiment, Maxwell’s demon plays the role of a gambler who knows when to quit while it's ahead.

Enlarge / In a new version of the classic 19th century thought experiment, Maxwell’s demon plays the role of a gambler who knows when to quit while it’s ahead. (credit: Aurich Lawson / Getty Images)

Entropy (aka the second law of thermodynamics) is a harsh mistress. If you think of the universe as a cosmic casino, the laws of thermodynamics amount to the house edge: you can’t win, you can’t break even, and—barring opening a portal to an alternate universe with different physical laws—you can’t get out of the game. You just have to keep playing, and hopefully come up with successful strategies to minimize your losses as much as possible—and maybe even come out ahead occasionally, at least in the short term.

That’s the essence of a new paper published in the journal Physical Review Letters, updating a classic 19th century thought experiment known as Maxwell’s demon, which provides a potential loophole to subvert the second law—at least temporarily. Now physicists have proposed a gambling version of the demon playing a slot machine, unable to control when the machine pays out (in terms of free energy available for work), but able to choose when to stop playing to maximize its “winnings.” The research might one day lead to improved efficiency of microscopic heat engines and motors.

As we’ve reported previously, around 1870, James Clerk Maxwell envisioned a tiny imp capable of creating order out of disorder in a closed container filled with gas. The imp accomplished this by making heat flow from a cold compartment to a hot one in apparent violation of the second law. The two compartments would be separated by a wall with a shutter covering a pinhole just large enough for a gas molecule to pass through. 

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#entropy, #maxwells-demon, #physics, #science, #second-law-of-thermodynamics, #thermodynamics

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This Is the Fastest Random-Number Generator Ever Built

A laser generates quantum randomness at a rate of 250 trillion bits per second and could lead to devices small enough to fit on a single chip

— Read more on ScientificAmerican.com

#physics, #tech

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Meet this year’s winners of the Dance Your PhD contest

Finnish researcher Jakub Kubecka won this year’s Dance Your PhD contest with a rap-based dance inspired by his work on the physics of atmospheric molecular clusters.

The global pandemic ruined most of our plans for 2020, but it couldn’t keep graduate students around the world from setting their thesis research to dance, submitting videos produced in strict adherence to local COVID-19 restrictions. With a little help from his friends, Ivo Neefjes and Vitus Besel, Jakub Kubecka, a Finnish graduate student, won with a rap-based dance about the physics of atmospheric molecular clusters. Incorporating computer animation and drone footage, Kubecka beat out 40 other contestants to take top honors, as well as winning the physics category.

As we’ve reported previously, the Dance Your PhD contest was established in 2008 by science journalist John Bohannon. It was previously sponsored by Science magazine and the American Association for the Advancement of Science (AAAS), and is now sponsored by AI company Primer, where Bohannon is director of science. Bohannon told Slate in 2011 that he came up with the idea while trying to figure out how to get a group of stressed-out PhD students in the middle of defending their theses to let off a little steam. So he put together a dance party at Austria’s Institute of Molecular Biotechnology, including a contest for whichever candidate could best explain their thesis topics with interpretive dance.

The contest was such a hit that Bohannon started getting emails asking when the next such contest would be—and Dance Your PhD has continued ever since. It’s now in its thirteenth year. There are four broad categories: physics, chemistry, biology, and social science, with a fairly liberal interpretation of what topics fall under each.

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#dance-your-phd, #gaming-culture, #physics, #science

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“Locked” for 300 years: Virtual unfolding has now revealed this letter’s secrets

In 1697, a man named Jacques Sennacque wrote a letter to his cousin, a French merchant named Pierre Le Pers, requesting a certified death certificate for another man named Daniel Le Pers (presumably also a relation). Sennacque sealed the letter with an intricate folding method known as “letterlocking,” a type of physical cryptography, to safeguard the contents from prying eyes. That letter was never delivered or opened. More than 300 years later, researchers have virtually “unlocked” the letter to reveal its contents for the first time, right down to the watermark in the shape of a bird. They described their results in a new paper published in the journal Nature Communications.

Co-author Jana Dambrogio, a conservator at MIT Libraries, coined the term “letterlocking” after discovering such letters while a fellow at the Vatican Secret Archives in 2000. The Vatican letters dated back to the 15th and 16th centuries, and they featured strange slits and corners that had been sliced off. Dambrogio realized that the letters had originally been folded in an ingenious manner, essentially “locked” by inserting a slice of the paper into a slit, then sealing it with wax. It would not have been possible to open the letter without ripping that slice of paper—evidence that the letter had been tampered with.

Dambrogio has been studying the practice of letterlocking ever since, often creating her own models to showcase different techniques. The practice dates back to the 13th century—at least in Western history—and there are many different folding and locking techniques that emerged over the centuries. Queen Elizabeth I, Machiavelli, Galileo Galilei, and Marie Antoinette are among the famous personages known to have employed letterlocking for their correspondence.

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#digital-humanities, #gaming-culture, #history, #physics, #science, #virtual-unfolding, #x-ray-microtomography

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Major Physics Society Will Not Meet in Cities with Racist Policing Records

The American Physical Society’s new criteria for conference venues seem to be unique among scientific societies

— Read more on ScientificAmerican.com

#physics, #policyethics, #the-sciences

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5 Picture Books About the Wonders of Science

Fossils, flowers, galaxies and a rare “lefty” snail.

#biology-and-biochemistry, #books-and-literature, #chemistry, #children-and-childhood, #el-fathi-mickael, #flowers-and-plants, #fossils, #fossils-from-lost-worlds-book, #genetics-and-heredity, #hahn-daniel, #hubble-space-telescope, #hubble-edwin, #ignotofsky-rachel, #laverdunt-damien, #marcero-deborah, #marinov-isabelle, #medicine-and-health, #nobel-prizes, #paleontology, #physics, #popova-maria, #rajcak-helene, #science-and-me-book, #science-and-technology, #snails, #space-and-astronomy, #stars-and-galaxies, #the-boy-whose-head-was-filled-with-stars-a-life-of-edwin-hubble-book, #the-snail-with-the-right-heart-a-true-story-book, #whats-inside-a-flower-and-other-questions-about-sciencenature-book, #winter-ali, #zhu-ping-illustrator

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Lone high-energy neutrino likely came from shredded star in distant galaxy

The remains of a shredded star formed an accretion disk around the black hole whose powerful tidal forces ripped it apart. This created a cosmic particle accelerator spewing out fast subatomic particles.

Enlarge / The remains of a shredded star formed an accretion disk around the black hole whose powerful tidal forces ripped it apart. This created a cosmic particle accelerator spewing out fast subatomic particles. (credit: DESY, Science Communication Lab)

Roughly 700 million years ago, a tiny subatomic particle was born in a galaxy far, far away, and began its journey across the vast expanses of our universe. That neutrino finally reached the Earth’s South Pole last October, setting off detectors buried deep beneath the Antarctic ice. A few months earlier, a telescope in California had recorded a bright glow emanating from the friction of that same distant galaxy—evidence of a so-called “tidal disruption event” (TDE), most likely the result of a star being shredded by a supermassive black hole.

According to two new papers (here and here) published in the journal Nature Astronomy, that lone neutrino was likely born from the TDE, which serves as a cosmic-scale particle accelerator near the center of the distant galaxy, spewing out high-energy subatomic particles as the star’s matter is consumed by the black hole. This finding also sheds light on the origin of ultrahigh-energy cosmic rays, a question that has puzzled astronomers for decades.

“The origin of cosmic high-energy neutrinos is unknown, primarily because they are notoriously hard to pin down,” said co-author Sjoert van Velzen, a postdoc at New York University at the time of the discovery. “This result would be only the second time high-energy neutrinos have been traced back to their source.”

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#astronomy, #black-holes, #multi-messenger-astronomy, #physics, #science, #tidal-forces

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Mystery of Spinning Atomic Fragments Solved at Last

New experiments have answered the decades-old question of how pieces of splitting nuclei get their spins

— Read more on ScientificAmerican.com

#physics, #the-sciences

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Scientists create new class of “Turing patterns” in colonies of E. coli

Scientists have shown how a new class of Turing patterns work by using synthetic biology to create them from scratch in the lab.

Shortly before his death, Alan Turing published a provocative paper outlining his theory for how complex, irregular patterns emerge in nature—his version of how the leopard got its spots. These so-called Turing patterns have been observed in physics and chemistry, and there is growing evidence that they also occur in biological systems. Now a team of Spanish scientists has managed to tweak E. coli in the laboratory so that the colonies exhibit branching Turing patterns, according to a recent paper published in the journal Synthetic Biology.

“By using synthetic biology, we have a unique opportunity to interrogate biological structures and their generative potential,” said co-author Ricard Solé of Universitat Pompeu Fabra in Barcelona, Spain, who is also an external professor at the Santa Fe Institute. “Are the observed mechanisms found in nature to create patterns the only solutions to generate them, or are there alternatives?” (Synthetic biology typically involves stitching together stretches of DNA—which can be found in other organisms, and be entirely novel—and inserting into an organism’s genome.)

In synthetic biology, scientists typically stitch together long stretches of DNA and insert them into an organism’s genome. These synthesized pieces of DNA could be genes that are found in other organisms or they could be entirely novel.

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#biochemistry, #biophysics, #e-coli, #physics, #science, #symmetry-breaking, #synthetic-biology, #turing-patterns

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New Supernova Alert System Promises Early Access to Spectacles in Space

Upgrades to the SuperNova Early Warning System (SNEWS) detection system offer advance notice of impending blasts

— Read more on ScientificAmerican.com

#physics, #space, #the-sciences

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When physics met dance: Marie Curie and Loïe Fuller in Belle Époque Paris

Poster from the Belle Epoque joins together two black-and-white photographs of women.

Enlarge / Radiant: The Scientist, the Dancer, and a Friendship Forged in Light explores the lives of Marie Curie and Loïe Fuller. (credit: Aurich Lawson / Getty Images)

Both the arts and the sciences flourished in Paris during the years of the so-called Belle Époque at the dawn of the 20th century. This was when Nobel Prize-winning physicist Marie Curie and her husband, Pierre, made their breakthrough discoveries in radioactivity, discovering two new elements. At the same time, a modern dancer and pioneer in theatrical lighting named Loïe Fuller, who was all the rage in Paris, dreamed of incorporating radium into her stage act. Science writer and communicator Liz Heinecke brings the live of these two visionary women together in an illuminating new biography, Radiant: The Scientist, the Dancer, and a Friendship Forged in Light.

The details of Marie Curie’s life are very well-documented and well-known. She left her native Poland and moved to Paris at 14 to pursue a degree in science, living in abject poverty while studying and conducting research. She met a chemist named Pierre Curie, and they began collaborating, eventually falling in love and getting married in 1895. The Curies had been married for six months when Wilhelm Roentgen discovered X-rays (winning the very first Nobel Prize in physics in 1901). Soon after, Henri Becquerel published his insight that uranium salts emitted rays that would fog a photographic plate in early 1896. Becquerel’s uranium rays so fascinated Marie that she made them the focus of her own research. 

With Pierre, she uncovered evidence of two new elements they dubbed polonium and radium. The couple shared the 1903 Nobel Prize in Physics with Becquerel for their work developing a theory of radioactivity—she was the first woman to be so honored. After Pierre’s tragic death in a 1906 street accident, Marie developed new techniques for isolating radioactive isotopes from pitchblende and eventually succeeded in isolating radium in 1910. She won a second Nobel Prize (this time in chemistry) in 1911 for the discovery of polonium and radium. She remains the only woman to win the Nobel Prize twice and the only person to do so in two different scientific fields.

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#books, #dance, #gaming-culture, #loie-fuller, #marie-curie, #physics, #science

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Astronomers: A comet fragment, not an asteroid, killed off the dinosaurs

Harvard astronomers have a new theory about the origin of the comet that led to the extinction of the dinosaurs.

Some 66 million years ago, a catastrophic event occurred that wiped out three-quarters of all plant and animal species on Earth, most notably taking down the dinosaurs. An errant asteroid from the asteroid belt has been deemed the most likely culprit. However, in a new paper published in Scientific Reports, Harvard astronomers offer an alternative: a special kind of comet—originating from a field of debris at the edge of our solar system known as the Oort cloud—that was thrown off course by Jupiter’s gravity toward the Sun. The Sun’s powerful tidal forces then ripped pieces off the comet, and one of the larger fragments of this “cometary shrapnel” eventually collided with Earth.

The most widely accepted explanation for what triggered that catastrophic mass extinction is known as the “Alvarez hypothesis,” after the late physicist Luis Alvarez and his geologist son, Walter. In 1980, they proposed that the extinction event may have been caused by a massive asteroid or comet hitting the Earth. They based this conclusion on their analysis of sedimentary layers at the Cretaceous-Paleogene boundary (the K-Pg boundary, formerly known as the K-T boundary) found all over the world, which included unusually high concentrations of iridium—a metal more commonly found in asteroids than on Earth. (That same year, Dutch geophysicist Jan Smit independently arrived at a similar conclusion.)

Since then, scientists have identified a likely impact site: a large crater in Chicxulub, Mexico, in the Yucatan Peninsula, first discovered by geophysicists in the late 1970s. The impactor that created it was sufficiently large (between 11 and 81 kilometers, or 7 to 50 miles) to melt, shock, and eject granite from deep inside the Earth, probably causing a megatsunami and ejecting vaporized rock and sulfates into the atmosphere. This in turn had a devastating effect on global climate, leading to mass extinction.

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#astronomy, #astrophysics, #chicxulub, #comets, #cretaceous, #dinosaurs, #physics, #science

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Snowflake Structure Still Mystifies Physicists

Their final shape depends on an array of temperature, humidity, and wind speed variables

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#physics, #the-sciences

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Aliens Must Be Out There

Why aren’t we looking for them?

#extraterrestrial-life, #loeb-abraham-1962, #physics, #planets, #solar-system, #space-and-astronomy, #stars-and-galaxies, #sun

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Electrons, Photons, Gluons, Quarks: A Nobel-Winning Physicist Explains It All

In “Fundamentals,” Frank Wilczek describes his own love for physics and details what we all need to understand about the forces that shape our physical world.

#books-and-literature, #fundamentals-ten-keys-to-reality-book, #physics, #space-and-astronomy, #wilczek-frank-a

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Einsteinium Is Mysterious. Scientists Have Unlocked Some of Its Secrets.

Number 99 on the periodic table does not occur naturally and is difficult to make and store, challenging researchers who want to study it.

#chemistry, #einstein-albert, #laboratories-and-scientific-equipment, #nature-journal, #physics, #radiation, #research

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A curious observer’s guide to quantum mechanics, pt. 5: Catching a wave

A curious observer’s guide to quantum mechanics, pt. 5: Catching a wave

Enlarge (credit: Aurich Lawson / Getty Images)

One of the quietest revolutions of our current century has been the entry of quantum mechanics into our everyday technology. It used to be that quantum effects were confined to physics laboratories and delicate experiments. But modern technology increasingly relies on quantum mechanics for its basic operation, and the importance of quantum effects will only grow in the decades to come. As such, physicist Miguel F. Morales has taken on the herculean task of explaining quantum mechanics to laypeople in this seven-part series (no math, we promise). Below is the fifth story in the series, but you can always find the starting story plus a landing page for the entire series thus far on site.

Sung to the abbess’s lines in “Maria” from The Sound of Music:

“How do you catch a wave like Maria? How do you grab a cloud and pin it down? Oh, how do you solve a particle like Maria? How do you hold a moonbeam in your hand?”

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#features, #physics, #quantum-mechanics, #science

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A Heroic Effort to Measure Helium

After an intense game of cat and mouse with different particles, atomic physicists have measured the radius of the helium nucleus five times more precisely than before. Christopher Intagliata reports.

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#physics, #the-sciences

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Remastered images reveal how far Alan Shepard hit a golf ball on the Moon

This image consists of six photographs taken from the Apollo 14 Lunar Module, enhanced and stitched into a single panorama to show the landing scene, along with the location from where Alan Shepard hit two golf balls. Both astronaut's PLSS' (life-support backpacks) can also be seen at left.

Enlarge / This image consists of six photographs taken from the Apollo 14 Lunar Module, enhanced and stitched into a single panorama to show the landing scene, along with the location from where Alan Shepard hit two golf balls. Both astronaut’s PLSS’ (life-support backpacks) can also be seen at left. (credit: NASA / JSC / ASU / Andy Saunders)

Fifty years ago this week, NASA astronaut Alan B. Shepard Jr. made space history when he took a few golf swings on the Moon during the Apollo 14 mission, successfully hitting two golf balls across the lunar surface. Space enthusiasts have debated for decades just how far that second ball traveled. It seems we now have an answer, thanks to the efforts of imaging specialist Andy Saunders, who digitally enhanced archival images from that mission and used them to estimate the final resting spots of the golf balls.

Saunders, who has been working with the United States Golf Association (USGA) to commemorate Shepard’s historical feat, announced his findings in a Twitter thread. Saunders concluded that the first golf ball Shepard hit traveled roughly 24 yards, while the second golf ball traveled 40 yards.

Shepard’s fondness for cheeky irreverence had popped up occasionally during his successful pre-NASA naval career, most notably when he was a test pilot at the Naval Air Station Patuxent River in Maryland. He was nearly court-martialed for looping the Chesapeake Bay Bridge during a test flight, but fortunately, his superiors intervened. When President Dwight D. Eisenhower established NASA in 1959, Shepard was selected as one of the seven Mercury astronauts. (The others were Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, and Deke Slayton.)

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#alan-shepard, #apollo-14, #golf, #moon, #nasa-history, #physics, #science, #space

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Galaxy-Size Gravitational-Wave Detector Hints at Exotic Physics

Recent results from a pulsar timing array, which uses dead stars to hunt for gravitational waves, has scientists speculating about cosmic strings and primordial black holes

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#physics, #the-sciences

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New study cracks the case of why food sticks to center of nonstick pans

Eggs frying in a pan have been arranged to look like a smiling face.

Enlarge / Foods will sometimes get stuck to a heated surface, even if oil or a nonstick frying pan is used. Scientists have concluded that convection may be to blame. (credit: Dan Tentler/via Getty Images)

Home cooks around the world have relied on nonstick cookware for decades for quick and easy cleanup after preparing meals. But sometimes food will get stuck to the center of nonstick pans anyway. A new paper published in the journal Physics of Fluids offers a likely explanation—food sticks because of the same underlying mechanism that gives rise to the coffee ring effect and so-called “wine tears.”

The first nonstick frying pans were made possible by the invention of Teflon in 1938 by a chemist named Roy Plunkett, who was researching possible new chlorofluorocarbon refrigerants as part of a joint venture with DuPont. In April of that year, Plunkett later recalled, his assistant selected one of the cylinders they were using to store tetrafluoroethylene gas (TFE) at dry-ice temperatures until the canisters were ready to be chlorinated for their experiments. When the assistant opened the valve, the gas did not flow under its own pressure from the container, as expected.

Puzzled, the researchers opened the container only to find the gas was gone. In its stead, they found a white powder. The TFE had polymerized into a waxy solid called polytetrafluoroethylene (PTFE), which proved to have some interesting properties: it was chemically inert and heat-resistant, and it had very low surface friction. Perhaps it wasn’t useful as a refrigerant, but it proved to be a terrific nonstick coating.

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#fluid-dynamics, #physics, #science

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The Skin-Deep Physics of Sidewinder Snakes

A close-up on snake skin helped scientists work out what might help certain snakes navigate sandy surfaces.

#deserts, #physics, #proceedings-of-the-national-academy-of-sciences, #sand-and-gravel, #skin, #snakes, #your-feed-animals, #your-feed-science

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The Cosmological Constant Is Physics’ Most Embarrassing Problem

Physicists have new ideas about why the energy of empty space is so much weaker than it is predicted to be

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#features, #physics, #space, #the-sciences

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