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Physicists Observe New Phase in Quantum Condensate of Light Apr 2, 2021 by Enrico de Lazaro Physicists at the University of Bonn have experimentally observed a new, previously unknown phase in the photon Bose-Einstein condensate. The Bose-Einstein condensate is a gas of atoms so dense and cold that their matter waves lose their individuality and condense into a ‘superatom wave.’ It was predicted in the 1920s by Satyendra Nath Bose and Albert Einstein and was eventually created in the lab in the 1990s at the University of Colorado Boulder, MIT and Rice University using laser cooling and evaporative cooling techniques....

Lattice Confinement Fusion NASA Detects Lattice Confinement Fusion A team of NASA researchers seeking a new energy source for deep-space exploration missions, recently revealed a method for triggering nuclear fusion in the space between the atoms of a metal solid. Their research was published in two peer-reviewed papers in the top journal in the field, Physical Review C, Volume 101 (April, 2020): “Nuclear fusion reactions in deuterated metals” and “Novel nuclear reactions observed in bremsstrahlung-irradiated deuterated metals.” Nuclear fusion is a process that produces energy when two nuclei join to form a heavier nucleus. “Scientists are interested in fusion, because...

Plutonium is generally thought of as an artificial element created by humans, primarily to make the pits of nuclear weapons, but naturally occurring plutonium can be found in ancient rocks. Plutonium 244 is the longest lived isotope of Plutonium, but it's not easy to make, and finding this specific isotope in interstellar dust grains laid down on the ocean floors tells us important things about the formation of the elements that make up the Earth.Based on this paper:60Fe and 244Pu deposited on Earth constrain the r-process yields of recent nearby supernovae A. Wallner et al

(NASA/CXC/UMass/Q.D. Wang; NRF/SARAO/MeerKAT) SPACE ------------------------------------------------------------------------------- The center of the Milky Way is a strange and wild place. There dwells our galactic nucleus - a supermassive black hole 4 million times the mass of the Sun, a beast named Sgr A*. It's probably the most extreme environment in our galaxy, dominated by Sgr A*'s gravitational and magnetic fields. It's also very hard to see into, even though it's only 25,800 light-years away: The region is shrouded by thick clouds of dust and gas that obscure some wavelengths of light. But if we use technology to tweak our vision into the invisible...

Structure of the new carbon network. The upper part shows schematically the linking of the carbon atoms, forming squares, hexagons, and octagons. The lower part is an image of the network, obtained with high-resolution microscopy. Credit: University of Marburg, Aalto University ================================================================================ Carbon exists in various forms. In addition to diamond and graphite, there are recently discovered forms with astonishing properties. For example graphene, with a thickness of just one atomic layer, is the thinnest known material, and its unusual properties make it an extremely exciting candidate for applications like future electronics and high-tech engineering. In graphene, each carbon atom...

The quantum world is notoriously weird. Single particles can be in two places at once, for example. Only by making an observation do we force it to 'choose'. Before an observation we can only assign probabilities to the likely outcomes. Such a picture cannot be reconciled with a smooth, continuous fabric of space-time. According to Einstein, space-time is warped by matter and energy, but quantum physics says matter and energy exist in multiple states simultaneously — they can be both here and over there. According to Einstein, space-time is like a stage that remains in place whether actors are treading...

Matter and antimatter are always created (or destroyed) in equal amounts. But there appears to be a dearth of antimatter in the universe. What happened to it?

Sailing through the smooth waters of vacuum, a photon of light moves at around 300 thousand kilometers (186 thousand miles) a second. This sets a firm limit on how quickly a whisper of information can travel anywhere in the Universe. While this law isn't likely to ever be broken, there are features of light which don't play by the same rules. Manipulating them won't hasten our ability to travel to the stars, but they could help us clear the way to a whole new class of laser technology. Physicists have been playing hard and fast with the speed limit of...

“Black dwarf supernovae”. They sound quite dramatic! And indeed, they may be the last really exciting events in the Universe.It’s too early to be sure. There could be plenty of things about astrophysics we don’t understand yet—and intelligent life may throw up surprises even in the very far future. But there’s a nice scenario here:• M. E. Caplan, Black dwarf supernova in the far future, Monthly Notices of the Royal Astronomical Society 497 (2020), 4357–4362.First, let me set the stage. What happens in the short run: say, the first 1023 years or so?For a while, galaxies will keep colliding. These...

What’s the price of an accurate clock? Entropy, a new study has revealed. Entropy — or disorder — is created every time a clock ticks. Now scientists working with a tiny clock have proven a simple relationship: The more accurate a clock runs, the more entropy it generates. "If you want your clock to be more accurate, you’ve got to pay for it,” study co-author Natalia Ares, a physicist at the University of Oxford, told Live Science. “Every time we measure time, we are increasing the universe’s entropy." As we go forward in time, the second law of thermodynamics states...

Faster than light travel is the only way humans could ever get to other stars in a reasonable amount of time. Credit: NASA The closest star to Earth is Proxima Centauri. It is about 4.25 light-years away, or about 25 trillion miles (40 trillion km). The fastest ever spacecraft, the now-in-space Parker Solar Probe will reach a top speed of 450,000 mph. It would take just 20 seconds to go from Los Angeles to New York City at that speed, but it would take the solar probe about 6,633 years to reach Earth’s nearest neighboring solar system. If humanity ever...

Scientists have discovered a new type of uranium that is the lightest ever known. The discovery could reveal more about a weird alpha particle that gets ejected from certain radioactive elements as they decay. The newfound uranium, called uranium-214, is an isotope, or a variant of the element, with 30 more neutrons than protons, one fewer neutron than the next-lightest known uranium isotope. Because neutrons have mass, uranium-214 is much lighter than more common uranium isotopes, including uranium-235, which is used in nuclear reactors and has 51 extra neutrons. This newfound isotope isn't just lighter than others, but it also...

As humans, we know we are conscious because we experience and feel things. Yet scientists and great thinkers are unable to explain what consciousness is and they are equally baffled about where it comes from."Consciousness — or better, conscious experience — is obviously a part of reality," said Johannes Kleiner, a mathematician and theoretical physicist at the Munich Center For Mathematical Philosophy, Germany. "We're all having it but without understanding how it relates to the known physics, our understanding of the universe is incomplete."With that in mind, Kleiner is hoping math will enable him to precisely define consciousness. Working with...

A satellite experiment has revealed that the heaviest known neutron star is unexpectedly large, which suggests that the matter in the star’s inner core is less “squeezable” than some models predict. NICER measures the size of a neutron star by tracking the x-ray emission from “hot spots” on the surface as the star rotates. These spots occur at the magnetic poles of the star, where the field slams particles onto the star surface. Neutron stars are “cosmic zombies”­—corpses of massive stars that collapsed in violent explosions after running out of fuel. By studying these ultradense objects, researchers hope to understand...

Sheffield University said the mathematician may have benefited from "colonial-era activity" as it looks to overhaul its physics curriculumStudents learning about the mathematician and scientist’s three laws of motion, the core of modern physics, could see changes in their teaching to explain the “global origins and historical context” of his theories Students learning about the mathematician and scientist’s three laws of motion, the core of modern physics, could see changes in their teaching to explain the “global origins and historical context” of his theories Sir Isaac Newton has been labelled as a potential beneficiary of “colonial-era activity” in draft plans...

The thorny thought experiment has been turned into a real experiment — one that physicists use to probe the physics of information ============================================================= It took physicists 115 years to tame Maxwell’s Demon. The universe bets on disorder. Imagine, for example, dropping a thimbleful of red dye into a swimming pool. All of those dye molecules are going to slowly spread throughout the water. Physicists quantify this tendency to spread by counting the number of possible ways the dye molecules can be arranged. There’s one possible state where the molecules are crowded into the thimble. There’s another where, say, the molecules...

Why is sugar not transparent? Because light that penetrates a piece of sugar is scattered, altered and deflected in a highly complicated way. However, as a research team from TU Wien (Vienna) and Utrecht University (Netherlands) has now been able to show, there is a class of very special light waves for which this does not apply: for any specific disordered medium—such as the sugar cube you may just have put in your coffee—tailor-made light beams can be constructed that are practically not changed by this medium, but only attenuated. The light beam penetrates the medium, and a light pattern...

In major international tests, the physics-defying EmDrive has failed to produce the amount of thrust proponents were expecting. In fact, in one test at Germany’s Dresden University, it didn’t produce any thrust at all. Is this the end of the line for EmDrive?

TAE Technologies, the world’s largest private fusion company, has announced it will have a commercially viable nuclear fusion power plant by 2030, which puts it years—or even decades—ahead of other fusion technology companies. The California-based company has raised $880 million in funding for its hydrogen-boron reactor. This reactor isn’t a traditional tokamak or stellarator; instead, it uses a confined particle acceleration mechanism that produces and confines plasma. All fusion technology has plasma, which mimics the extreme reactions that power all the stars—it’s what we’re emulating when we make fusion energy experiments. “Plasma is an oozy substance; the challenge of containing...

The long-awaited first results from the Muon g-2 experiment at the U.S. Department of Energy’s Fermi National Accelerator Laboratory show fundamental particles called muons behaving in a way that is not predicted by scientists’ best theory, the Standard Model of particle physics. This landmark result, made with unprecedented precision, confirms a discrepancy that has been gnawing at researchers for decades. The strong evidence that muons deviate from the Standard Model calculation might hint at exciting new physics. Muons act as a window into the subatomic world and could be interacting with yet undiscovered particles or forces. “Today is an extraordinary...