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More than any other equation in physics, E = mc² is recognizable and profound. But what do we actually learn about reality from it? ===================================================================== This 1934 photograph shows Einstein in front of a blackboard, deriving special relativity for a group of students and onlookers. Although special relativity is now taken for granted, it was revolutionary when Einstein first put it forth, and doesn't even describe his most famous equation, which is E = mc². - Public Domain ====================================================================== Key Takeaways: * First introduced way back in 1905, Einstein’s most famous equation, E = mc², put forth the mathematical formula...

Unofficial reports of 10 antihelium nuclei smacking into the International Space Station have inspired theoretical physicists to speculate beyond our current models in search of an explanation. While a small handful of cosmic particles might appear trivial, the signature of the antihelium shower is strange enough for researchers to treat the event like a rainstorm in a desert. In their recently published analysis, scientists from the Perimeter Institute for Theoretical Physics in Canada and Johns Hopkins University in the US make a case for considering physics outside of the currently accepted Standard Model, going as far as suggesting dark matter...

Dreams of a world powered by antigravity got quashed by a particle physics today. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ It turns out that Einstein was right yet again. A recent experiment just proved that antigravity doesn’t exist and we probably won’t ever get to use antimatter to levitate or build a perpetual motion machine or power warp drives (sorry, Star Trek). Antimatter itself is very real. Made of particles that mostly behave like regular matter, but their electrical charges are reversed, an anti-proton looks just like a proton but has a negative charge, while an anti-electron (or positron) looks and moves just like an...

1.) How did the Universe begin? What “type” of inflation occurred? What preceded and/or caused inflation? 2.) What explains neutrino mass? Are neutrinos Dirac or Majorana particles? Are there heavy, sterile neutrino species? 3.) Why is our Universe matter-dominated? More matter than antimatter permeates the Universe. 4.) What is dark matter? Its effects are understood, not its underlying cause. 5.) What is dark energy? Its properties indicate a constant, positive spatial energy density.

Image showing counter-propagating high-intensity lasers producing gamma radiation. (Toma Toncian) ============================================================================= A new study by scientists has demonstrated how researchers may be able to create an accelerating jet of antimatter from light. A team of physicists has shown that high-intensity lasers can be used to generate colliding gamma photons – the most energetic wavelengths of light – to produce electron-positron pairs. This, they say, could help us understand the environments around some of the Universe's most extreme objects: neutron stars. The process of creating a matter-antimatter pair of particles – an electron and a positron – from photons is called...

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?

Observations of galactic rotation curves give one of the strongest lines of evidence pointing towards the existence of dark matter, a non-baryonic form of matter that makes up an estimated 85% of the matter in the observable Universe. Current assessments of galactic rotation curves are based upon a framework of Newtonian accounts of gravity, a new article suggests that if this is substituted with a general relativity-based model, the need to recourse to dark matter is relieved, replaced by the effects of gravitomagnetism.

On December 6, 2016, a high-energy particle called an electron antineutrino hurtled to Earth from outer space at close to the speed of light carrying 6.3 petaelectronvolts (PeV) of energy. Deep inside the ice sheet at the South Pole, it smashed into an electron and produced a particle that quickly decayed into a shower of secondary particles. The interaction was captured by a massive telescope buried in the Antarctic glacier, the IceCube Neutrino Observatory. IceCube had seen a Glashow resonance event, a phenomenon predicted by Nobel laureate physicist Sheldon Glashow in 1960. With this detection, scientists provided another confirmation of...

Pip-squeak particles called neutrinos are dishing out more than scientists had bargained for.A particle detector has spotted a puzzling abundance of the lightweight subatomic particles and their antimatter partners, antineutrinos, physicists report May 30 at arXiv.org. The finding mirrors a neutrino excess found more than two decades ago. And that match has researchers wondering if a new type of particle called a sterile neutrino — one even more shadowy than the famously elusive ordinary neutrinos — might be at large.Such a particle, if it exists, would transform the foundations of particle physics and could help solve cosmic puzzles like the...

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...

Scientists have produced the firmest evidence yet of so-called sterile neutrinos, mysterious particles that pass through matter without interacting with it at all. The first hints these elusive particles turned up decades ago. But after years of dedicated searches, scientists have been unable to find any other evidence for them, with many experiments contradicting those old results. These new results now leave scientists with two robust experiments that seem to demonstrate the existence of sterile neutrinos, even as other experiments continue to suggest sterile neutrinos don't exist at all. That means there's something strange happening in the universe that is...

IT TRIGGERED A SUBATOMIC CASCADE — AND COULD HAVE AN AVALANCHE OF IMPLICATIONS FOR THE FUTURE OF PHYSICS.Crash Course Scientists have now confirmed that an unusually powerful particle of antimatter crashed down into Antarctica back in December 2016. The collision seems to have triggered a subatomic cascade effect called Glashow resonance, Live Science reports, which is a theoretical phenomenon that requires more energy to set off than even the most powerful particle accelerators can provide. Scientists didn’t expect to see tangible evidence of Glashow resonance, but now that they have it helps further confirm the Standard Model of subatomic physics....

For the first time, researchers have performed a version of the famous double-slit experiment with antimatter particles.The double-slit experiment demonstrates one of the fundamental tenets of quantum physics: that pointlike particles are also waves. In the standard version of the experiment, particles travel through a pair of slits in a solid barrier. On a screen on the other side, an interference pattern typical of waves appears. Crests and troughs emerging from each slit reinforce each other or cancel each other out as they overlap, creating alternating bands of high and low particle density on the screen.This kind of experiment has...

The laws of physics are such that one photon just passes by another with zero interaction. But in a new experiment inside the world's most powerful atom smasher, researchers got a glimpse of the impossible: photons bumping into each other. The answer lies in one of the most inscrutable and yet delicious aspects of modern physics, and it goes by the funky name of quantum electrodynamics. In this picture of the subatomic world, the photon isn't necessarily a photon. Well, at least, it's not always a photon. Particles like electrons and photons and all the other -ons continually flip back...

It takes 1 trillion times the age of the universe for a xenon-124 sample to shrink by half For the first time, researchers have directly observed an exotic type of radioactive decay called two-neutrino double electron capture.The decay, seen in xenon-124 atoms, happens so sparingly that it would take 18 sextillion years (18 followed by 21 zeros) for a sample of xenon-124 to shrink by half, making the decay extremely difficult to detect. The long-anticipated observation of two-neutrino double electron capture, reported in the April 25 Nature, lays the groundwork for researchers to glimpse a yet unseen, even rarer version...

The finding keeps open the possibility that the particles come from dark matter New observations of the whirling cores of dead stars have deepened the mystery behind a glut of antimatter particles raining down on Earth from space. The particles are antielectrons, also known as positrons, and could be a sign of dark matter — the exotic and unidentified culprit that makes up the bulk of the universe’s mass. But more mundane explanations are also plausible: Positrons might be spewed from nearby pulsars, the spinning remnants of exploded stars, for example. But researchers with the High-Altitude Water Cherenkov Observatory, or...

The recent finding, detailed in the journal Science today (Nov. 17), concerns positrons, the antimatter complements of electrons. High-energy particles, usually protons, traveling across the galaxy can create pairs of positrons and electrons when they interact with dust and gas in space, study co-author Hao Zhou, at Los Alamos National Lab, told Space.com. In 2008, the space-based PAMELA detector measured unexpectedly high numbers of earthbound positrons. This was about 10 times what they were expecting to see, according to Zhou. ... Zhou's team made detailed measurements of the gamma-rays coming from the direction of two nearby pulsars — Geminga and its companion...

Ever since the existence of antimatter was proposed in the early 20th century, scientists have sought to understand how relates to normal matter, and why there is an apparent imbalance between the two in the Universe. To do this, particle physics research in the past few decades has focused on the anti-particle of the most elementary and abundant atom in the Universe – the antihydrogen particle. Until recently, this has been very difficult, as scientists have been able to produce antihydrogen, but unable to study it for long before it annihilated. But according to recent a study that was published...

Matter and antimatter appear to be perfect mirror images of each other as far as anyone can see, scientists have discovered with unprecedented precision, foiling hope of solving the mystery as to why there is far more matter than antimatter in the universe. Everyday matter is made up of protons, neutrons or electrons. These particles have counterparts known as antiparticles — antiprotons, antineutrons and positrons, respectively — that have the same mass but the opposite electric charge. (Although neutrons and antineutrons are both neutrally charged, they are each made of particles known as quarks that possess fractional electrical charges, and...

Physicists find ways to increase antihydrogen production 18 hours ago by Lisa Zyga feature Antihydrogen consists of an antiproton and a positron. Credit: public domain (Phys.org)—There are many experiments that physicists would like to perform on antimatter, from studying its properties with spectroscopic measurements to testing how it interacts with gravity. But in order to perform these experiments, scientists first need some antimatter. Of course, they won't be finding any in nature (due to antimatter's tendency to annihilate in a burst of energy when it comes in contact with ordinary matter), and creating it in the lab has proven to...