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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.

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...

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...

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...

Explanation: From where do these neutrinos come? The IceCube Neutrino Observatory near the South Pole of the Earth has begun to detect nearly invisible particles of very high energy. Although these rarely-interacting neutrinos pass through much of the Earth just before being detected, where they started remains a mystery. Pictured here is IceCube's Antarctic lab accompanied by a cartoon depicting long strands of detectors frozen into the crystal clear ice below. Candidate origins for these cosmic neutrinos include the violent surroundings of supermassive black holes at the centers of distant galaxies, and tremendous stellar explosions culminating in gamma ray bursts...

Analysis of data from the National Science Foundation-(NSF) funded 10-m South Pole Telescope (SPT) in Antarctica provides new support for the most widely accepted explanation of dark energy, the source of the mysterious force that is responsible for the accelerating expansion of the universe. The results begin to hone in on the tiny mass of the neutrinos, the most abundant particles in the universe, which until recently were thought to be without mass. The SPT data strongly support Albert Einstein's cosmological constant—the leading model for dark energy—even though researchers base the analysis on only a fraction of the SPT data...

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...

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....

EARTH'S natural radioactivity has been measured for the first time. The measurement will help geologists find out to what extent nuclear decay is responsible for the immense quantity of heat generated by Earth. Our planet's heat output drives the convection currents that churn liquid iron in the outer core, giving rise to Earth's magnetic field. Just where this heat comes from is a big question. Measurements of the temperature gradients across rocks in mines and boreholes have led geologists to estimate that the planet is internally generating between 30 and 44 terawatts of heat. Some of this heat comes from...