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An international team of astrophysicists has made a puzzling discovery while analyzing certain star clusters. The finding challenges Newton's laws of gravity, the researchers write in their publication. Instead, the observations are consistent with the predictions of an alternative theory of gravity. However, this is controversial among experts. The results have now been published in the Monthly Notices of the Royal Astronomical Society. In their work, the researchers investigated open star clusters. These are formed when thousands of stars are born within a short time in a huge gas cloud. As they "ignite," the galactic newcomers blow away the remnants...

A new conjecture in physics challenges the leading “theory of everything.”On June 25, Timm Wrase awoke in Vienna and groggily scrolled through an online repository of newly posted physics papers. One title startled him into full consciousness. The paper, by the prominent string theorist Cumrun Vafa of Harvard and his collaborators, conjectured a simple formula dictating which kinds of universes are allowed to exist and which are forbidden, according to string theory. The leading candidate for a “theory of everything” weaving the force of gravity together with quantum physics, string theory defines all matter and forces as vibrations of tiny...

A rendering of the entangled atoms within the interferometer. Credit: Steven Burrows, Thompson Group/JILA A team of researchers at JILA has for the first time successfully combined two of the “spookiest” features of quantum mechanics to make a better quantum sensor: entanglement between atoms and delocalization of atoms. JILA is a physical science research institute operated by the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder. For the first time, scientists have successfully combined two of the “spookiest” features of quantum mechanics to make a better quantum sensor: entanglement between atoms and delocalization of atoms....

One of the earliest realizations in the history of quantum mechanics is that matter has a wave-like property. Other physicists soon confirmed ...electrons scattered off a thin foil before landing on a target. The way the electrons scattered was more characteristic of a wave than a particle. What, exactly, is a wave of matter? Schrödinger...developed his famous equation to describe the behavior of those waves... But Schrödinger's idea flew in the face of more experimental tests. For example, even though an electron acted like a wave midflight, when it reached a target, it landed as a single, compact particle, so...

When a massive star collapsed in the Cassiopeia constellation, it generated a supernova explosion with some of the fastest shockwaves in the Milky Way. These speedy shock waves are one of the reasons the Cassiopeia A (Cas A) supernova remnant was chosen to be our Imaging X-ray Polarimetry Explorer’s (IXPE) first observed object. This composite image, made of data from IXPE, the Chandra Observatory, and the Hubble Telescope, shows Cas A. IXPE’s investigation of Cas A from Jan. 11 to Jan. 29, 2022, added crucial information about the behavior of exploded stars’ magnetic fields: scientists found that the magnetic fields...

Astronomers have published a major finding: A black hole has been "burping" out energy from a small star it was observed shredding in 2018, after two years in which it didn't eject any such material. How unusual is this? "Super unusual," Yvette Cendes, an astronomer at the Center for Astrophysics, Harvard and Smithsonian and lead author of the paper, tells NPR. "We've never really seen this before to this degree." Researchers made the discovery when they used a powerful radio telescope facility — the Very Large Array in New Mexico – to check in on some two dozen black holes...

Strange Long-Lasting Pulse of High-Energy Radiation Swept Over Earth Record Breaking Gamma Ray Burst Astronomers think GRB 221009A represents the birth of a new black hole formed within the heart of a collapsing star. In this illustration, the black hole drives powerful jets of particles traveling near the speed of light. The jets pierce through the star, emitting X-rays and gamma rays as they stream into space. Credit: NASA/Swift/Cruz deWildeNASA’s Swift and Fermi Missions Detect Exceptional Cosmic BlastAn unusually bright and long-lasting pulse of high-energy radiation swept over Earth Sunday, October 9, captivating astronomers around the world. The intense emission...

Periodically, these gravitational behemoths will devoir stars and other objects in their vicinity, releasing tremendous amounts of light and radiation. In October 2018, astronomers witnessed one such event when observing a black hole in a galaxy located 665 million light-years from Earth....another team from the Harvard & Smithsonian Center for Astrophysics noticed something unprecedented when they examined the same black hole three years later. As they explained in a recent study, the black hole was shining very brightly because it was ejecting...leftover material from the star at half the speed of light. [T]he team observed the outburst while revisiting data...

Quantum computers have the potential to outperform classical computers on several complex tasks, yet many challenges will need to be overcome before they reach their full potential. In the meantime, physicists and computer scientists have been trying to realistically estimate the capabilities that quantum computing technologies will exhibit in the near future. Quantum simulations—realizations of quantum systems manifested using programmable simulation devices—have proved particularly valuable for determining the near-term potential of quantum computers. One approach that can be investigated using quantum simulations is quantum annealing, an optimization process based on engineered quantum fluctuations. The quantum simulation of the 1D Ising...

an illustration of the boundaries of the solar system. The planetary system sits inside a glowing bubble, with a large blue bubble wrapped around it. bright lights resembling comets, possibly representative of cosmic rays, are unable to penetrate An illustration showing the Solar System inside the heliosphere, with the termination shock and heliopause represented by two bubbles, one inside the other. (NASA) The bubble of space encasing the Solar System might be wrinkled, at least sometimes. Data from a spacecraft orbiting Earth has revealed ripple structures in the termination shock and heliopause: shifting regions of space that mark one of...

Data from a spacecraft orbiting Earth has revealed ripple structures in the termination shock and heliopause: shifting regions of space that mark one of the boundaries between the space inside the Solar System, and...interstellar space. ...Sun affects the space around it...solar wind, a constant supersonic flow of ionized plasma. It blows out past the planets and the Kuiper Belt, eventually petering out in the great emptiness between the stars. The point at which this flow falls below the speed at which sound waves can travel through the diffuse interstallar medium is called the termination shock, and the point at which...

Three scientists jointly won this year's Nobel Prize in physics on Tuesday for their work on quantum information science that has significant applications, for example in the field of encryption. Alain Aspect, John F. Clauser and Anton Zeilinger were cited by the Royal Swedish Academy of Sciences for discovering the way that particles known as photons can be linked, or "entangled," with each other even when they are separated by large distances. "Quantum information science is a vibrant and rapidly developing field," said Eva Olsson, a member of the Nobel committee. "It has broad and potential implications in areas such...

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.

In 2020, Ranga Dias, a physicist at the University of Rochester, and his colleagues published a sensational result in Nature, featured on its cover. They claimed to have discovered a room-temperature superconductor: a material in which electric current flows frictionlessly without any need for special cooling systems. Although it was just a speck of carbon, sulfur, and hydrogen forged under extreme pressures, the hope was that someday the material would lead to variants that would enable lossless electricity grids and inexpensive magnets for MRI machines, maglev railways, atom smashers, and fusion reactors. On Monday Nature retracted the study, citing data...

The discovery is a step towards much more accessible superconductivity. It may be possible to develop superconductors that operate at room temperature with further knowledge of the relationship between spin liquids and superconductivity, which would transform our daily lives. Superconductors offer enormous technical and economic promise for applications such as high-speed hovertrains, MRI machines, efficient power lines, quantum computing, and other technologies. However, their usefulness is limited since superconductivity requires extremely low temperatures. It is highly challenging to integrate them with modern technology because of this demanding and costly requirement. The electrical resistance of a superconductor has a specific critical...

For even a modest number of electrons and cutting-edge computational approaches, the problem requires serious computing power. That's because when electrons interact, their fates can become quantum mechanically entangled: Even once they're far apart on different lattice sites, the two electrons can't be treated individually, so physicists must deal with all the electrons at once rather than one at a time. With more electrons, more entanglements crop up, making the computational challenge exponentially harder. One way of studying a quantum system is by using what's called a renormalization group. That's a mathematical apparatus physicists use to look at how the...

The object, named FRB 20201124A, was detected with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China and described in a new paper led by astronomer Heng Xu of Peking University in China. So far most evidence points to a magnetar – a neutron star with extraordinarily strong magnetic fields – as a source of FRB emissions like this. If FRB 20201124A is indeed from one of these wild cosmic beasts, it's looking like an unusual specimen. Polarization refers to the orientation of light waves in three-dimensional space. By examining how much that orientation has changed since the light departed...

Sun-like star co-orbiting with black hole Gaia BH1 is a Sun-like star co-orbiting with a black hole estimated at 10 times the Sun's mass. (ESO/L. Calcada) In 1916, Karl Schwarzchild theorized the existence of black holes as a resolution to Einstein's field equations for his Theory of General Relativity. By the mid-20th century, astronomers began detecting black holes for the first time using indirect methods, which consisted of observing their effects on surrounding objects and space. Since the 1980s, scientists have studied supermassive black holes (SMBHs), which reside at the center of most massive galaxies in the Universe. And by...

We know that colliding two particles in empty space can sometimes cause additional particles to emerge. There are even theories that a strong enough electromagnetic field could create matter and antimatter out of nothing itself. Big Think reports, in early 2022, a group of researchers created strong enough electric fields in their laboratory to level the unique properties of a material known as graphene. With these fields, the researchers were able to enable the spontaneous creation of particle-antiparticle pairs from nothing at all. This proved that creating matter from nothing is indeed possible, a theory first proposed by Julian Schwinger,...

The Microscope satellite, a CNES mission with ESA cooperation to test the universality of freefall. The equivalence principle states that all objects should fall freely under gravity at the same rate, independent of their mass and composition, and is the founding principle of General Relativity, Albert Einstein’s theory of gravity. This principle has been tested by experiments on the ground, confirming with an accuracy of 1013 that objects with different characteristics experience the same acceleration from Earth’s gravity. By taking the experiment into space, Microscope will extend the range of measurements to an accuracy of 1015, enabling scientists to...