Free Republic

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...

Physicists studying collisions of gold ions at the Relativistic Heavy Ion Collider (RHIC), a U.S. Department of Energy Office of Science user facility for nuclear physics research at DOE's Brookhaven National Laboratory, are embarking on a journey through the phases of nuclear matter—the stuff that makes up the nuclei of all the visible matter in our universe. A new analysis of collisions conducted at different energies shows tantalizing signs of a critical point—a change in the way that quarks and gluons, the building blocks of protons and neutrons, transform from one phase to another. The findings, just published by RHIC's...

America's STEM classrooms are devolving — wasting valuable class time with toys, barely applicable coding games, and victim-mentality nonsense.If you ask any administrator about the future of education, he’ll likely mention the blending of science, technology, engineering, and mathematics: STEM. Indeed, it’s so attractive to schools, billions of dollars are spent every year by corporations, startups, and the U.S. federal government in an 1850s-style “gold rush” of gadgetry and glittering lights. To stand out from the competition and get into classrooms, curriculum developers, policymakers, and advocacy groups have begun to scam the education market by forsaking common-sense STEM principles in...

SPARC could be the first fusion reactor to produce net energy—10 years before ITER and in a machine 10 times smaller. A startup chasing the dream of plentiful, safe, carbon-free electricity from fusion, the energy source of the Sun, has settled on a site, timetable, and key technology for building its compact reactor. Flush with more than $200 million from investors, including Bill Gates’s Breakthrough Energy, 3-year-old Commonwealth Fusion Systems announced today that later this year it will start to build its first test reactor, dubbed SPARC, in a new facility in Devens, Massachusetts, not far from its current...

The researchers' lab-grown black hole was made of a flowing gas of approximately 8,000 rubidium atoms cooled to nearly absolute zero and held in place by a laser beam. They created a mysterious state of matter, known as a Bose-Einstein Condensate (BEC), which allows thousands of atoms to act together in unison as though they were a single atom. Using a second laser beam, the team created a cliff of potential energy, which caused the gas to flow like water rushing down a waterfall, thereby creating an event horizon where one half of the gas was flowing faster than the...

by Technion - Israel Institute of Technology Credit: CC0 Public Domain Using AI and computer automation, Technion researchers have developed a 'conjecture generator' that creates mathematical conjectures, which are considered to be the starting point for developing mathematical theorems. They have already used it to generate a number of previously unknown formulas. The study, which was published in the journal Nature, was carried out by undergraduates from different faculties under the tutelage of Assistant Professor Ido Kaminer of the Andrew and Erna Viterbi Faculty of Electrical Engineering at the Technion. The project deals with one of the most fundamental elements...

There are supermassive black holes. There are ultramassive black holes. How large can these strange objects grow? Well, there could be something even bigger than ultramassive: stupendously large black holes, according to the latest research. Such hypothetical black holes - larger than 100 billion times the mass of the Sun - have been explored in a new paper which names them SLABs, an acronym that stands for "Stupendously LArge Black holeS". "We already know that black holes exist over a vast range of masses, with a supermassive black hole of 4 million solar masses residing at the centre of our...

Researchers used the ALMA telescope array in Chile to discover the quasar A quasar is a type of supermassive black hole that is releasing a lot of energy This object was discovered when the universe was just 670 million years old The discovery can help researchers better understand how these objects form Its age and size brings into doubt theories they were formed from collapsed star clusters, with researchers suggesting they instead feast on cold hydrogen gas =========================================================== The most distant supermassive black hole known to science has been detected by astronomers - and it is more than 13 billion...

Researchers at Columbia Engineering report today that they have developed the first nanomaterial that demonstrates "photon avalanching," a process that is unrivaled in its combination of extreme nonlinear optical behavior and efficiency. The realization of photon avalanching in nanoparticle form opens up a host of sought-after applications, from real-time super-resolution optical microscopy, precise temperature and environmental sensing, and infrared light detection, to optical analog-to-digital conversion and quantum sensing. Avalanching processes—where a cascade of events is triggered by series of small perturbations—are found in a wide range of phenomena beyond snow slides, including the popping of champagne bubbles, nuclear explosions, lasing,...

The largest black holes in the universe... sit at the centers of almost every galaxy in the cosmos. Even the Milky Way has one, a monster at 4 million solar masses, designated as Sagittarius A*. ...[A]s far as we know, the only way to form black holes is through the deaths of massive stars. When they die, they leave behind a black hole a few times more massive than the sun. To get to supergiant status, they have to merge with other black holes and/or consume as much gas as possible, bulking up all those millions of solar masses... Either...

Quantum teleportation is a "disembodied" transfer of quantum states from one location to another. The quantum teleportation of a qubit is achieved using quantum entanglement, in which two or more particles are inextricably linked to each other. If an entangled pair of particles is shared between two separate locations, no matter the distance between them, the encoded information is teleported. In a paper published in PRX Quantum, the team presents for the first time a demonstration of a sustained, long-distance teleportation of qubits made of photons (particles of light) with fidelity greater than 90%. The qubits were teleported over a...

Like all stars, our Sun is powered by the fusion of hydrogen into heavier elements. Nuclear fusion is not only what makes stars shine, it is also a primary source of the chemical elements that make the world around us. Much of our understanding of stellar fusion comes from theoretical models of atomic nuclei, but for our closest star, we also have another source: neutrinos created in the Sun’s core.Whenever atomic nuclei undergo fusion, they produce not only high energy gamma rays but also neutrinos. While the gamma rays heat the Sun’s interior over thousands of years, neutrinos zip out...

Theory was first postulated in 1930s. Scientists this week announced the landmark detection of elusive particles generated from the fusion of hydrogen in the Sun, confirming a nearly-100-year-old theory about the ways in which many stars generate energy. In a paper published in Nature, a team of researchers called the Borexino Collaboration reported detecting the presence of neutrinos produced during the carbon–nitrogen–oxygen cycle of fusion deep within the Sun. The scientists stated that the energy produced in the CNO cycle represents just a small fraction of the total energy output of our Sun, but “in massive stars, this is the...

Earth Is a Whole Lot Closer to Our Galaxy's Supermassive Black Hole Than We Thought MICHELLE STARR 27 NOVEMBER 2020 It seems that Earth has been misplaced. According to a new map of the Milky Way galaxy, the Solar System's position isn't where we thought it was. Not only is it closer to the galactic centre - and the supermassive hole therein, Sagittarius A* - it's orbiting at a faster clip. It's nothing to be concerned about; we're not actually moving closer to Sgr A*, and we're in no danger of being slurped up. Rather, our map of the Milky...

White dwarf stars in globular cluster NGC 6397. (NASA, ESA, and H. Richer/University of British Columbia) SPACE ====================================================================== When stars like the Sun reach the end of their lives, the object that remains is a white dwarf. This is the star's shrunken, naked core, no longer capable of nuclear fusion. It shines, but only with residual heat, slowly cooling over billions of years until it's completely cold and dark. But not all white dwarfs cool the same way. Last year, astronomers found a certain type of massive white dwarf stars cool more slowly than others, as though they have...

Explanation: What's creating these long glowing streaks in the sky? No one is sure. Known as Strong Thermal Emission Velocity Enhancements (STEVEs), these luminous light-purple sky ribbons may resemble regular auroras, but recent research reveals significant differences. A STEVE's great length and unusual colors, when measured precisely, indicate that it may be related to a subauroral ion drift (SAID), a supersonic river of hot atmospheric ions thought previously to be invisible. Some STEVEs are now also thought to be accompanied by green picket fence structures, a series of sky slats that can appear outside of the main auroral oval that...

Artist’s impression of the cold brown dwarf BDR J1750+3809. The blue loops depict the magnetic field lines. Charged particles moving along these lines emit radio waves that LOFAR detected. Some particles eventually reach the poles and generate aurorae similar to the northern lights on Earth. Credit: ASTRON/Danielle Futselaar ========================================================================== Gemini North and IRTF Confirm LOFAR Discovery For the first time, astronomers have used observations from the LOFAR radio telescope, the NASA IRTF, operated by the University of Hawai‘i, and the international Gemini Observatory, a Program of NSF’s NOIRLab, to discover and characterize a cold brown dwarf. The object, designated BDR...

Artist's impression of a galaxy surrounded by gravitational distortions due to dark matter. Galaxies live inside larger concentrations of invisible dark matter (coloured purple in this image), however the dark matter's effects can be seen by looking at the deformations of background galaxies. Credit: Swinburne Astronomy Productions - James Josephides ========================================================================== A small team of astronomers have found a new way to 'see' the elusive dark matter haloes that surround galaxies, with a new technique 10 times more precise than the previous-best method. The work is published in Monthly Notices of the Royal Astronomical Society. Scientists currently estimate that up...

Schematic depiction of the asymmetric supercapacitor with the porous COF as the negative electrode shown on the left. Credit: KAUST, Osama Shekhah ========================================================================= Carefully designed covalent organic frameworks could make supercapacitor electrodes that have a greater ability to store electric charge. A porous organic material created at KAUST could significantly improve energy storage and delivery by supercapacitors, which are devices that are able to deliver quick and powerful bursts of energy. Supercapacitors use technology that is significantly different from the reversible chemical reactions used in rechargeable batteries. They store electrical energy by building up a separation of positive and electric...