MIT’s Cheetah 3 robot can now leap and gallop across rough terrain, climb a staircase littered with debris, and quickly recover its balance when suddenly yanked or shoved, all while essentially blind.
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Electric current is everywhere, from powering homes to controlling the plasma that fuels fusion reactions to possibly giving rise to vast cosmic magnetic fields. Now, scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have found that electrical currents can form in ways not known before. The novel findings could give researchers greater ability to bring the fusion energy that drives the sun and stars to Earth.
“It’s very important to understand which processes produce electrical currents in plasma and which phenomena could interfere with them,” said Ian Ochs, graduate student in Princeton Universitys Program in Plasma Physics and lead author of a paper selected as a featured article in Physics of Plasmas. “They are the primary tool we use to control plasma in magnetic fusion research.”
It’s like something out of Stranger Things, but with fewer Demogorgons and less of the sinister darkness: physicists have flipped reality on its head, creating their own ‘upside down’ by getting small boats to float underneath a levitating liquid.
Seeing it in action, you would think you were watching some kind of sci-fi movie effect, but it’s all to do with the forces of vertical vibration. It’s already been established that some carefully calibrated vertical shaking can keep liquid suspended inside a container, and here the team has taken advantage of the phenomenon.
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Giant balloons launched into the stratosphere to beam internet service to Earth have helped scientists measure tiny ripples in our upper atmosphere, uncovering patterns that could improve weather forecasts and climate models.
The ripples, known as gravity waves or buoyancy waves, emerge when blobs of air are forced upward and then pulled down by gravity. Imagine a parcel of air that rushes over mountains, plunges toward cool valleys, shuttles across land and sea and ricochets off growing storms, bobbing up and down between layers of stable atmosphere in a great tug of war between buoyancy and gravity. A single wave can travel for thousands of miles, carrying momentum and heat along the way.
Although lesser known than gravitational waves —undulations in the fabric of space-time— atmospheric gravity waves are ubiquitous and powerful, said Stanford University atmospheric scientist Aditi Sheshadri, senior author of a new study detailing changes in high-frequency gravity waves across seasons and latitudes. They cause some of the turbulence felt on airplanes flying in clear skies and have a strong influence on how storms play out at ground level.
“Gravitational waves from what could be the most massive black hole merger yet has been detected by researchers at the Laser Interferometer Gravitational-wave Observatory (LIGO) and its discovery is also raising questions about how massive black holes are formed.
When scientists made the first direct detection of gravitational waves from a binary black hole merger in February 2016, not only did they prove Einstein right, they also discovered another curious quirk; the audibl… See More.
The detection of the heaviest black hole merger to date is also the first clear detection of an ” intermediate-mass” black hole.
Scientists suggest that a counter-intuitive, hypothetical species of black holes may negate the standard model of cosmology, where dark energy is an inherent and constant property of spacetime that will result in an eventual cold death of the universe. “It’s the big elephant in the room,” says Claudia de Rham, a theoretical physicist at Imperial College London about dark energy, the mysterious, elusive phenomena that pushes the cosmos to expand so rapidly and which is estimated to account for 70% of the contents of the universe. “It’s very frustrating.”
Generic Objects of Dark Energy
Astronomers have known for two decades that the expansion of the universe is accelerating, but the physics of this expansion remains a mystery. In 1966, Erast Gliner, a young physicist at the Ioffe Physico-Technical Institute in Leningrad, proposed an alternative hypothesis that very large stars should collapse into what could be called Generic Objects of Dark Energy (GEODEs). These appear to be black holes when viewed from the outside but, unlike black holes, they contain dark energy instead of a singularity.
When searching for signs of life in the Universe, we tend to look for very specific things, based on what we know: a planet like Earth, in orbit around a star, and at a distance that allows liquid surface water. But there could, conceivably, be other forms of life out there that look like nothing that we have ever imagined before.
Just as we have extremophiles here on Earth — organisms that live in the most extreme and seemingly inhospitable environments the planet has to offer — so too could there be extremophiles out there in the wider Universe.
For instance, species that can form, evolve, and thrive in the interiors of stars. According to new research by physicists Luis Anchordoqui and Eugene Chudnovsky of The City University of New York, such a thing is indeed — hypothetically, at least — possible.
Black holes are celestial objects with such massive gravity that not even light can escape their clutches once it crosses the event horizon, or point-of-no-return. The event horizons of black holes lock secrets deep within them — secrets that could completely revolutionize our understanding of physics.
Unfortunately, for decades many scientists thought whatever information falls into a black hole might be lost forever. But new research suggests that ripples in space-time, or gravitational waves may carry a faint whisper of this hidden information by revealing the presence of wispy “hairs” on a black hole’s surface.
Hair may record the information swallowed by the gravitational monsters.
IAIFI will advance physics knowledge — from the smallest building blocks of nature to the largest structures in the universe — and galvanize AI research innovation.
The U.S. National Science Foundation (NSF) announced last week an investment of more than $100 million to establish five artificial intelligence (AI) institutes, each receiving roughly $20 million over five years. One of these, the NSF AI Institute for Artificial Intelligence and Fundamental Interactions (IAIFI), will be led by MIT ’s Laboratory for Nuclear Science (LNS) and become the intellectual home of more than 25 physics and AI senior researchers at MIT and Harvard, Northeastern, and Tufts universities.
By merging research in physics and AI, the IAIFI seeks to tackle some of the most challenging problems in physics, including precision calculations of the structure of matter, gravitational-wave detection of merging black holes, and the extraction of new physical laws from noisy data.
For the first time, pressure over 100 times that found in Earth’s core has been generated in a lab, setting a new record.
Using the highest-energy laser system in the world, physicists briefly subjected solid hydrocarbon samples to pressures up to 450 megabars, meaning 450 million times Earth’s atmospheric pressure at sea level.
That’s equivalent to the pressures found in the carbon-dominated envelopes of a rare type of white dwarf star — some of the densest objects in the known Universe. It could help us to better understand the effect those pressures have on changes in the stars’ brightness.
