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Do you remember in 1989 when two chemists announced they’d created a setup that created nuclear fusion at room temperature? Everyone was excited, but it eventually turned out to be very suspect. It wasn’t clear how they detected that fusion occurred and only a few of the many people who tried to replicate the experiment claimed success and they later retracted their reports. Since then, mentioning cold fusion is right up there with perpetual motion. Work does continue though, and NASA recently published several papers on lattice confinement fusion which is definitely not called cold fusion, although it sounds like...

A major new milestone has just been achieved in the quest for superconductivity. For the first time, physicists have achieved the resistance-free flow of an electrical current at room temperature - a positively balmy 15 degrees Celsius (59 degrees Fahrenheit). This has smashed the previous record of -23 degrees Celsius (-9.4 degrees Fahrenheit), and has brought the prospect of functional superconductivity a huge step forward. "Because of the limits of low temperature, materials with such extraordinary properties have not quite transformed the world in the way that many might have imagined," physicist Ranga Dias of the University of Rochester said...

In the early evening of Sunday, October 7, 1900 - 120 years ago - Max Planck found the functional form of the curve that we now know as the Planck distribution of black-body radiation. By my account, it was the birthdate of quantum mechanics. [In Comment #1 - a beautiful photo of Planck, Einstein, and Millikan at a dinner party]

Roger Penrose’s theoretical work demonstrated the objects could form. Reinhard Genzel and Andrea Ghez independently discovered a supermassive one at the center of the Milky Way. Roger Penrose, Reinhard Genzel, and Andrea Ghez are to be awarded the 2020 Nobel Prize in Physics for their theoretical and observational work on black holes, the Royal Swedish Academy of Sciences announced on Tuesday. Penrose will receive half the 10 million Swedish krona (roughly $1.1 million) prize; Ghez and Genzel will share the other half. Penrose, of the University of Oxford, helped place the previously idealized concept of a black hole on sound...

Researchers build circuit that harnessed the atomic motion of graphene to generate an electrical current that could lead to a chip to replace batteries. ============================================================================ A team of University of Arkansas physicists has successfully developed a circuit capable of capturing graphene’s thermal motion and converting it into an electrical current. “An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,” said Paul Thibado, professor of physics and lead researcher in the discovery. The findings, published in the journal Physical Review E, are proof of a theory the...

No one has yet managed to travel through time – at least to our knowledge – but the question of whether or not such a feat would be theoretically possible continues to fascinate scientists. As movies such as The Terminator, Donnie Darko, Back to the Future and many others show, moving around in time creates a lot of problems for the fundamental rules of the Universe: if you go back in time and stop your parents from meeting, for instance, how can you possibly exist in order to go back in time in the first place? It's a monumental head-scratcher...

Spaceflight Now | Breaking News | Relativity mission achieves two major milestones Relativity mission achieves two major milestones NASA-MSFC NEWS RELEASEPosted: March 6, 2002 The NASA Gravity Probe B (GP-B) Relativity Mission has successfully mated its science payload to its spacecraft and after successful systems testing, the GP-B space vehicle was shipped to Sunnyvale, Calif., on Feb. 9, 2002, to prepare for upcoming rigorous environmental tests. The Gravity Probe B spacecraft on a modal stand in preparation for environmental testing. Photo: Lockheed Martin  "These milestones are a huge accomplishment for this dedicated team," said Gravity Probe B program manager Rex ...

“Classical dynamics says if you know the state of a system at a particular time, this can tell us the entire history of the system,” said Germain Tobar, a student in the School of Mathematics and Physics at the University of Queensland. “This has a wide range of applications, from allowing us to send rockets to other planets and modeling how fluids flow.” “For example, if I know the current position and velocity of an object falling under the force of gravity, I can calculate where it will be at any time.” “However, Einstein’s theory of general relativity predicts the...

Some huge, some small. Some zip, some crawl. The cosmos is full of objects that defy expectations.... The biggest: UY Scuti Just like in the DC Universe, sometimes the clearest way for astronomers to express something is truly extraordinary is to add the prefix super. It’s the case with Superman, as well as with supergiant stars — a fitting category for the largest known star in the universe, UY Scuti. One day, the Sun will become a red giant. But if it had started its life with a dozen or so times its current mass, it could have eventually evolved...

When humanity finally detected the collision between two neutron stars in 2017, we confirmed a long-held theory - in the energetic fires of these incredible explosions, elements heavier than iron are forged. And so, we thought we had an answer to the question of how these elements - including gold - propagated throughout the Universe. But a new analysis has revealed a problem. According to new galactic chemical evolution models, neutron star collisions don't even come close to producing the abundances of heavy elements found in the Milky Way galaxy today. "Neutron star mergers did not produce enough heavy elements...

Futurism: Your paper argues that the universe might fundamentally be a neural network. How would you explain your reasoning to someone who didn’t know very much about neural networks or physics? Vitaly Vanchurin: There are two ways to answer your question. The first way is to start with a precise model of neural networks and then to study the behavior of the network in the limit of a large number of neurons. What I have shown is that equations of quantum mechanics describe pretty well the behavior of the system near equilibrium and equations of classical mechanics describes pretty well...

It would be extremely optimistic to suggest that we have a good handle on dark matter. But even the slight grasp we do have may be missing something important. New observations from the Hubble Space Telescope have found much higher concentrations of dark matter than expected in some galaxies, by over an order of magnitude. These concentrations are inconsistent with theoretical models, suggesting that there's a big gap in our understanding - the simulations could be incorrect, or there could be a property of dark matter we don't fully understand, according to the research team. "We have done a lot...

L-r: A non-rotating black hole; a rotating black hole; a boson star as they'd appear to the EHT. (Olivares et al., MNRAS, 2020 ===================================================================================== Last year, the astronomical community achieved an absolute wonder. For the very first time, the world collectively laid eyes on an actual image of the shadow of a black hole. It was the culmination of years of work, a magnificent achievement in both human collaboration and technical ingenuity. And, like the best scientific breakthroughs, it opened a whole new world of enquiry. For a team led by astrophysicist Hector Olivares from Radboud University in the Netherlands...

Explanation: SS 433 is one of the most exotic star systems known. Its unremarkable name stems from its inclusion in a catalog of Milky Way stars which emit radiation characteristic of atomic hydrogen. Its remarkable behavior stems from a compact object, a black hole or neutron star, which has produced an accretion disk with jets. Because the disk and jets from SS 433 resemble those surrounding supermassive black holes in the centers of distant galaxies, SS 433 is considered a micro-quasar. As illustrated in the animated featured video based on observational data, a massive, hot, normal star is locked in...

The information locked inside black holes could be detected by feeling their 'hair,' new research suggests. As far as we understand them (which, admittedly, is not very much), black holes are suspiciously simple objects. Regardless of what falls in... black holes can be described by three and only three simple numbers: charge, mass and spin. The reason this is suspicious is that something had to happen to all that juicy information that fell into those two black holes. The simplest solution is the theorem, first coined by the American physicist John Wheeler, that "black holes have no hair" — they...

NASA scientists have spotted what they are calling a “halo” around Andromeda. The halo, which is more like a huge bloom of plasma, stretches 1.3 million light-years into space. That’s roughly halfway to our own galaxy, which is an impressive feat. We often think of galaxies as self-contained collections of stars, planets, and gasses, but that’s simply not the case. The effects of a galaxy extend far beyond their outer edge. In fact, the line between the edge of a galaxy and empty space is so blurred that there’s hardly a real “edge” at all. In the case of Andromeda,...

Toroidal, or doughnut-shaped, tokamaks are prone to intense bursts of heat and particles, called edge localized modes (ELMs). These ELMs can damage the reactor walls and must be controlled to develop reliable fusion power. Fortunately, scientists have learned to tame these ELMs by applying spiraling rippled magnetic fields to the surface of the plasma that fuels fusion reactions. However, the taming of ELMs requires very specific conditions that limit the operational flexibility of tokamak reactors. Now, researchers at PPPL and GA have developed a model that... accurately reproduces the conditions for ELM suppression in the DIII-D National Fusion Facility that...

The so-called Fast Radio Burst repeats every 157 days with the power of millions of suns and its latest barrage arrived right on time last week. Known as FRB 121102, scientists hope that studying the strange blinkering signal could unlock the secret to what FRBs are and where they come from. Fast Radio Bursts are intense pulses of radio waves that last no longer than the blink of an eye and come from far beyond our Milky Way galaxy. Their origins are unknown. . The group’s findings, to The Astronomer’s Telegram, suggest the burst is currently in its active phase...

Stephen Hawking won accolades from his peers for having one of the most brilliant minds in science, but he never got a Nobel Prize because no one has yet proven his ideas. The Nobel committee looks for proof, not big ideas. Hawking was a deep thinker — a theorist — and his musings about black holes and cosmology have yet to get the lockdown evidence that accompanies the physics prizes, his fellow scientists said.

Exotic subatomic particles, sterile neutrinos, are no-shows in experiments, increasing doubts about their existence. University of Cincinnati physicists, as part of an international research team, are raising doubts about the existence of an exotic subatomic particle that failed to show up in twin experiments. UC College of Arts and Sciences associate professor Alexandre Sousa and assistant professor Adam Aurisano took part in an experiment at the Fermi National Accelerator Laboratory in search of sterile neutrinos, a suspected fourth "flavor" of neutrino that would join the ranks of muon, tau, and electron neutrinos as elementary particles that make up the known...