Keyword: stringtheory
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In the night sky, far south of the equator, there’s a curious collection of faint constellations embedded in the tapestry of stars. They do not bear the names of myths and legends, because the ancient Greeks couldn’t see them from the Northern Hemisphere. These constellations were charted later, in the mid-18th century, by a French astronomer who sailed south ... And just like a cluttered attic, this corner of sky has been hiding something truly remarkable. Astronomers have discovered a black hole in one of the constellations, the suitably named Telescopium. At just 1,000 light-years away, the black hole is...
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Experimenting with a magnetic field almost 1M times stronger than that of the Earth, researchers in the Scholes Group were able to modify the optoelectronic properties of model nonmagnetic organic chromophores. The modifications, according to the paper, arise from the induction of ring currents in the aromatic molecules. Aromatic ring currents can be understood as the proposal that electrons delocalized by aromaticity will move circularly when a magnetic field is applied perpendicular to the aromatic plane, typically nudging chemical shifts of nearby atoms in NMR spectroscopy. For the experiment, researchers chose a model aromatic chromophore called a phthalocyanine, which has...
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Work on this event is very preliminary, with astronomers madly scrambling to analyse the swathes of data. But many seem in agreement that it could finally point to the source of fast radio bursts (FRBs). "This sort of, in most people's minds, settles the origin of FRBs as coming from magnetars," astronomer Shrinivas Kulkarni of Caltech, and member of one of the teams, the STARE2 survey that also detected the radio signal, told ScienceAlert. Fast radio bursts are one of the most fascinating mysteries in the cosmos. They are extremely powerful radio signals from deep space, galaxies millions of light-years...
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What is the fundamental nature of reality? Is space-time — the four-dimensional fabric of our universe — ultimately smooth at the tiniest of scales, or something else? It seems impossible to measure, but with the power of advanced telescopes peering through billions of light-years of distance, researchers are beginning to look down. Deep down.
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New findings suggest laws of nature 'downright weird,' not as constant as previously thought by Lachlan Gilbert, University of New South Wales Scientists examining the light from one of the furthermost quasars in the universe were astonished to find fluctuations in the electromagnetic force. Credit: Shutterstock Not only does a universal constant seem annoyingly inconstant at the outer fringes of the cosmos, it occurs in only one direction, which is downright weird. Those looking forward to a day when science's Grand Unifying Theory of Everything could be worn on a t-shirt may have to wait a little longer as astrophysicists...
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Black holes are most often discussed in terms of their mass, but how much volume do these hefty, invisible objects actually have? Lurking at the center of the Milky Way is a gargantuan black hole that tips the scales at several million times the mass of the Sun. Like all black holes, this supermassive monster — called Sagittarius A* — devours anything that falls too close, including light. However, consuming material is just one way these monsters grow to truly astronomical sizes, reaching mindboggling weights. Although astronomers often talk about black holes as being gigantic objects, it’s important to remember...
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Credit: Skolkovo Institute of Science and Technology The search for coveted high-temperature superconductors is going to get easier with a new 'law within a law' discovered by Skoltech and MIPT researchers and their colleagues, who figured out a link between an element's position in the Periodic Table and its potential to form a high-temperature superconducting hydride. The new paper is published in the journal Current Opinion in Solid State & Materials Science. The research was supported by the Russian Science Foundation. Superconducting materials, with zero resistance and thus no dissipation of energy to heat, would be extremely useful for...
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Researchers pushing the limits of magnets as a means to create faster electronics published their proof of concept findings today, April 10, in the journal Science. . . . The team exploring methods for creating machines that operate at trillions of cycles per second includes the University of California, Santa Cruz and Riverside, Ohio State University, Oakland University (Michigan) and New York University, among others. Today's computers rely on ferromagnets (the same kind that stick to your refrigerator) to align the binary 1s and 0s that process and store information. Anti-ferromagnets are much more powerful, but their natural state, displaying...
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The image of a black hole has a bright ring of emission surrounding a "shadow" cast by the black hole. This ring is composed of a stack of increasingly sharp subrings that correspond to the number of orbits that photons took around the black hole before reaching the observer. Credit: George Wong (UIUC) and Michael Johnson (CfA) _________________________________________________________________________________ Last April, the Event Horizon Telescope (EHT) sparked international excitement when it unveiled the first image of a black hole. Today, a team of researchers have published new calculations that predict a striking and intricate substructure within black hole images from extreme...
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The dynamics of electrons change ever so slightly on each interaction with a photon. Physicists at ETH Zurich have now measured such interplay in its arguably purest form—by recording the attosecond-scale time delays associated with one-photon transitions in an unbound electron. The photoelectric effect, whereby photons impinging on matter cause the emission of electrons, is one of the quintessential effects of quantum mechanics. Einstein famously explained the key mechanism underlying the phenomenon in 1905, earning him the 1921 Nobel Prize in Physics. He built on a concept introduced five years earlier by Max Planck: Electromagnetic energy is absorbed and emitted...
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Nine hundred million years after the Big Bang, in the epoch of our universe's earliest galaxies, there was already a black hole 1 billion times the size of our sun. That black hole sucked in huge quantities of ionized gas, forming a galactic engine — known as a blazar — that blasted a superhot jet of bright matter into space. On Earth, we can still detect the light from that explosion more than 12 billion years later. Astronomers had previously discovered evidence of primeval supermassive black holes in slightly younger "radio-loud active galactic nuclei," or RL AGNs. RL AGNs are...
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The news: Honeywell, a US company best known for its home thermostats, has announced that it has built the world’s most powerful quantum computer. While all eyes were on IBM and Google, which last year knocked heads over quantum supremacy, Honeywell has been working quietly on quantum tech that it plans to make available to clients via the internet in the next three months. How it works: Most quantum computers, including those being developed by IBM and Google, are built around superconducting qubits, which use supercooled circuits. Honeywell’s quantum computer uses a different technology, called ion traps, which hold ions—the...
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Freeman J. Dyson, a mathematical prodigy who left his mark on subatomic physics before turning to messier subjects like Earth’s environmental future and the morality of war, died on Friday at a hospital near Princeton, N.J. He was 96. His daughter Mia Dyson confirmed the death. As a young graduate student at Cornell in 1949, Dr. Dyson wrote a landmark paper — worthy, some colleagues thought, of a Nobel Prize — that deepened the understanding of how light interacts with matter to produce the palpable world. The theory the paper advanced, called quantum electrodynamics, or QED, ranks among the great...
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String theory is perhaps the most controversial big idea in all of science today. On the one hand, it's a mathematically compelling framework that offers the potential to unify the Standard Model with General Relativity, providing a quantum description of gravity and providing deep insights into how we conceive of the entire Universe. On the other hand, its predictions are all over the map, untestable in practice, and require an enormous set of assumptions that are unsupported by an iota of scientific evidence. For perhaps the last 35 years, string theory has been the dominant idea in theoretical particle physics,...
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"We are sidestepping all of the scientific challenges that have held fusion energy back for more than half a century," says the director of an Australian company that claims its hydrogen-boron fusion technology is already working a billion times better than expected.
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The way the fabric of space and time swirls in a cosmic whirlpool around a dead star has confirmed yet another prediction from Einstein's theory of general relativity, a new study finds. That prediction is a phenomenon known as frame dragging, or the Lense-Thirring effect. It states that space-time will churn around a massive, rotating body. For example, imagine Earth were submerged in honey. As the planet rotated, the honey around it would swirl — and the same holds true with space-time. Satellite experiments have detected frame dragging in the gravitational field of rotating Earth, but the effect is extraordinarily...
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Prof Claudia de Rham’s ‘massive gravity’ theory could explain why universe expansion is accelerating Cosmologists don’t enter their profession to tackle the easy questions, but there is one paradox that has reached staggering proportions. Since the big bang, the universe has been expanding, but the known laws of physics suggest that the inward tug of gravity should be slowing down this expansion. In reality, though, the universe is ballooning at an accelerating rate. Scientists have come up with a name – dark energy – for the mysterious agent that is allowing the cosmos to expand so rapidly and which is...
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The death of this reigning physics paradigm, the Standard Model, has been predicted for decades. There are hints of its problems in the physics we already have. Strange results from laboratory experiments suggest flickers of ghostly new species of neutrinos beyond the three described in the Standard Model. And the universe seems full of dark matter that no particle in the Standard Model can explain. But recent tantalizing evidence might one day tie those vague strands of data together: Three times since 2016, ultra-high-energy particles have blasted up through the ice of Antarctica, setting off detectors in the Antarctic Impulsive...
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Scientists have captured the first ever footage of atoms bonding at a scale around half a million times smaller than the width of a human hair. Using advanced microscopy methods, the team of UK and German researchers captured the breaking of a chemical bond between two rhenium atoms. The video shows the two atoms to the left of the footage, between 0.1 and 0.3 nanometres, appearing as black blobs as they bond and break. Atoms are ‘the building blocks of the world’ and the matter around us is made up of layers and layers of atoms – unless they’re a...
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Gravitational waves are caused by calamitous events in the Universe. Neutron stars that finally merge after circling each other for a long time can create them, and so can two black holes that collide with each other. But sometimes there's a burst of gravitational waves that doesn't have a clear cause. One such burst was detected by LIGO/VIRGO on January 14, and it came from the same region of sky that hosts the star Betelgeuse. Yeah, Betelgeuse, aka Alpha Orionis. The star that has been exhibiting some dimming behaviour recently, and is expected to go supernova at some point in...
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