Keyword: steadystate
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Artist’s impression of the bright, very early active galactic nucleus that was found by Bañados and his colleagues, which has fundamental implications for black hole growth in the earliest billion or so years of cosmic history. Credit: NSF/AUI/NSF NRAO/B. Saxton ======================================================================================= Astronomers have spotted a young, blazing black hole that was already growing at a furious pace just one billion years after the Big Bang. This rare discovery provides a key to understanding how supermassive black holes formed in the universe’s earliest days. Astronomers have identified a crucial clue in understanding how supermassive black holes grew so quickly in the...
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Observations suggest that galaxies are moving apart at a higher rate than scientists have long expected. Many now wonder if the standard model of cosmology can fully explain what’s going on. Dan Scolnic is an associate professor of physics at Duke University. He and his team led a new study, published in the Astrophysical Journal Letters, that strengthens the case for a mismatch between data and predictions. Century of tracking
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The universe is expanding faster and faster, but not all scientists agree that dark energy is the cause. Perhaps, instead, our universe keeps colliding with and absorbing smaller 'baby universes,' a new theoretical study suggests. Our universe is expanding at an ever-accelerating rate — a phenomenon that all theories of cosmology agree upon but none can fully explain. Now, a new theoretical study offers an intriguing solution: Perhaps our universe is expanding because it keeps colliding with and absorbing "baby" parallel universes. Studies of the cosmic microwave background, the afterglow of the Big Bang, have revealed that our universe is...
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The Hubble tension grows: new data shows the Universe’s expansion defies current physics models, suggesting our understanding of cosmology may need a major overhaul. Credit: SciTechDaily.com New research confirms the Universe is expanding faster than theoretical models predict, intensifying the Hubble tension. Using precise measurements of the Coma cluster, scientists recalibrated the cosmic distance ladder, suggesting flaws in existing cosmological models. Expanding Universe: A Startling Discovery The Universe appears to be expanding faster than expected — faster than theoretical models predict and beyond what our current understanding of physics can explain. New measurements have confirmed earlier, highly debated results showing...
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Dismantling the belief in a static universe, Edwin Hubble's revolutionary observations in the 1920s laid the groundwork for our understanding of a continually expanding cosmos. However, we must seek to reconcile this theory with observations that are consistent with a non-expanding universe, writes Tim Anderson. You have been taught that the universe began with a Big Bang, a hot, dense period about 13.8 billion years ago. And the reason we believe this to be true is because the universe is expanding and, therefore, was smaller in the past. The Cosmic Microwave Background is the smoking gun for the Big Bang,...
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The Big Rip: New Theory Ends Universe by Shredding EverythingBy Robert Roy BrittSenior Science Writerposted: 12:04 pm ET06 March 2003 A rather harrowing new theory about the death of the universe paints a picture of "phantom energy" ripping apart galaxies, stars, planets and eventually every speck of matter in a fantastical end to time.Scientifically it is just about the most repulsive notion ever conceived.The speculative but serious cosmology is described as a "pretty fantastic possibility" even by its lead author, Robert Caldwell of Dartmouth University. It explains one possible outcome for solid astronomical observations made in the late 1990s...
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In a nutshell: * Astronomers studying the nearby Coma galaxy cluster have found new evidence that the universe is expanding about 9% faster than predicted by our current physics models – a discrepancy known as the Hubble tension. This finding strengthens concerns that our fundamental understanding of cosmic evolution may need revision. * The research team measured precise distances to 13 supernovae within the Coma cluster, determining it lies about 98.5 million light-years from Earth – significantly closer than the 111.8 million light-years predicted by models based on observations of the early universe. This difference is too large to be...
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There’s a crisis brewing in the cosmos. Measurements over the past few years of the distances and velocities of faraway galaxies don’t agree with the increasingly controversial “standard model” of the cosmos that has prevailed for the past two decades. Astronomers think that a 9 percent discrepancy in the value of a long-sought number called the Hubble Constant, which describes how fast the universe is expanding, might be revealing something new and astounding about the universe. The cosmos has been expanding for 13.8 billion years and its present rate of expansion, known as the Hubble constant, gives the time elapsed...
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It’s an idea straight out of the schoolyard: that you might one day accidentally count so high that you break the laws of math. A new preprint (that has not yet been peer-reviewed) seems to have done just that, however – and it could have huge ramifications for how we ought to understand infinity. It’s fitting that such a baffling result would have come from set theory: it’s an area with a reputation for being abstract and often counter-intuitive; it has its own esoteric alphabet and language; and it’s famous for results that seem either too basic to have even...
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The hot Big Bang is often touted as the beginning of the Universe. But there's one piece of evidence we can't ignore that shows otherwise. The notion of the Big Bang goes back nearly 100 years, when the first evidence for the expanding Universe appeared. If the Universe is expanding and cooling today, that implies a past that was smaller, denser, and hotter. In our imaginations, we can extrapolate back to arbitrarily small sizes, high densities, and hot temperatures: all the way to a singularity, where all of the Universe’s matter and energy was condensed in a single point. For...
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Goodbye Big Bang, hello black hole? A new theory of the universe's creation Enlarge Artist’s conception of the event horizon of a black hole. Credit: Victor de Schwanberg/Science Photo Library Could the famed "Big Bang" theory need a revision? A group of theoretical physicists suppose the birth of the universe could have happened after a four-dimensional star collapsed into a black hole and ejected debris. Before getting into their findings, let's just preface this by saying nobody knows anything for sure. Humans obviously weren't around at the time the universe began. The standard theory is that the universe grew from...
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The new role that quantum information plays in gravity sets the scene for a dramatic unification of ideas in physics One of the hottest new ideas in physics is that gravity is an emergent phenomena; that it somehow arises from the complex interaction of simpler things. A few month's ago, Erik Verlinde at the the University of Amsterdam put forward one such idea which has taken the world of physics by storm. Verlinde suggested that gravity is merely a manifestation of entropy in the Universe. His idea is based on the second law of thermodynamics, that entropy always increases over...
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The James Webb Space Telescope (Credit: NASA) The James Webb Space Telescope has confirmed controversial Hubble Telescope measurements that seemingly contradict the standard model of cosmology, giving rise to what is known as the ‘Hubble Tension,’ according to new findings involving the most extensive study of the universe’s expansion ever conducted. Confirmation of the decades-long Hubble Tension, which reveals that the universe is expanding faster than cosmological models predict, has sent astrophysicists back to the drawing board in search of previously unknown physics that could account for the measurements, potentially rewriting the standard model. “The discrepancy between the observed expansion...
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Baffled by the expansion of the universe? You're not alone. Even astronomers frequently get it wrong. The expansion of the universe may be the most important fact we have ever discovered about our origins. You would not be reading this article if the universe had not expanded. Human beings would not exist. Cold molecular things such as life-forms and terrestrial planets could not have come into existence unless the universe, starting from a hot big bang, had expanded and cooled. The formation of all the structures in the universe, from galaxies and stars to planets and Scientific American articles, has...
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A new Einstein cross is discovered March 18, 2019, Instituto de Astrofísica de Canarias The newly discovered Einstein Cross J2211-3050. An elliptical galaxy (the yellow object) is acting as a lens, producing the four blue objects (marked ABCD) that are the images of a galaxy about 3 times more distant. With GTC it was possible to isolate and disperse the light of objects ABC, demonstrating that they belong to the same light source. Credit: Hubble Space Telescope Credit: Instituto de Astrofísica de Canarias This study, which has combined images from the Hubble Space Telescope with spectroscopic observations from the GTC,...
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Whirlpool Galaxy, photographed by the Webb Space Telescope. Photo: NASA ESA Webb / A Adamo ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Introduction by Asia Times Science Editor Jonathan Tennenbaum In September Eric Lerner created a sensation with his Asia Times article, “Saying goodbye to the Big Bang,” arguing that the Big Bang theory is contradicted by an overwhelming mass of astronomical evidence accumulated over decades, including recent data from NASA’s James Webb Space Telescope. Eric Lerner ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The data forced even a pair of hitherto staunch advocates of the Big Bang, the well-known astrophysicists Adam Frank and Marcelo Gleiser, to admit that something must be...
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SYDNEY (Reuters) - A team of Australian scientists has proposed that the speed of light may not be a constant, a revolutionary idea that could unseat one of the most cherished laws of modern physics -- Einstein's theory of relativity. The team, led by theoretical physicist Paul Davies of Sydney's Macquarie University, say it is possible that the speed of light has slowed over billions of years. If so, physicists will have to rethink many of their basic ideas about the laws of the universe. "That means giving up the theory of relativity and E=mc squared and all that sort...
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1 The placebo effect DON'T try this at home. Several times a day, for several days, you induce pain in someone. You control the pain with morphine until the final day of the experiment, when you replace the morphine with saline solution. Guess what? The saline takes the pain away. This is the placebo effect: somehow, sometimes, a whole lot of nothing can be very powerful. Except it's not quite nothing. When Fabrizio Benedetti of the University of Turin in Italy carried out the above experiment, he added a final twist by adding naloxone, a drug that blocks the effects...
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A supermassive black hole sits inside the galaxy Centaurus A, seen in an artist's conception. Like part of a cosmic Russian doll, our universe may be nested inside a black hole that is itself part of a larger universe.In turn, all the black holes found so far in our universe—from the microscopic to the supermassive—may be doorways into alternate realities.According to a mind-bending new theory, a black hole is actually a tunnel between universes—a type of wormhole. The matter the black hole attracts doesn't collapse into a single point, as has been predicted, but rather gushes out a "white hole"...
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Cambridge physicist Stephen Hawking and his CERN colleague Thomas Hertog have proposed a radical new approach to understanding the universe that studies it from the "top down" rather than the "bottom up" as in traditional models. The approach acknowledges that the universe did not have just one unique beginning and history but a multitude of different beginnings and histories, and that it has experienced them all. But because most of these other alternative histories disappeared very early after the Big Bang to leave behind the universe we observe today, the best way to understand the past, they say, is to...
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