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Dark energy DOES exist and it's increasingly driving our universe apart, scientists claim. By Daily Mail Reporter Updated: 17:14 GMT, 20 May 2011 Dark energy is driving our universe apart at accelerating speeds, according to a five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time. The study offers new support for the favoured theory of how dark energy works - as a constant force, uniformly affecting the universe and propelling its runaway expansion. Its findings are based on results from Nasa's space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

Scientists measured the separations between pairs of galaxies and observed that dark energy (represented by purple grid) is a smooth, uniform force that dominates over the effects of gravity (green grid) But they contradict an alternate theory, where gravity, not dark energy, is the force pushing space apart. 'The results tell us that dark energy is a cosmological constant, as Einstein proposed.

Is the Universe Infinite? The Great Dark Cosmic Side Coincidence. [Earthlit Moon: Dorst/Druckmüller] One of the biggest mysteries — and wonders — in the known Universe flies over our heads every day. Or night, to be more precise. Alas, few human beings ever come to realize these questions even exist, much less ponder about them. Although often quoted polls suggest some people are still in the Middle Ages, most do know that planets are more or less spherical and revolve around the Sun.

Or at least that they are not just points of light on a celestial bowl over a Flat Earth. Now, then why does we always see the same Moon? One of the first images of the far side of the Moon, captured on 1959 The simple answer is that the Moon’s rotation period coincides with its orbital one, which in turn means that the time it takes for the Moon to turn around itself is the same as it takes for it to fly around Earth. Science does have an answer for it, and it involves the most traditional of the forces.

Neat, huh? The Great Cosmic Coincidence Or… not. Amoon. The Universe - Solved. Enigma: Black Holes Glow with a Hot Ring of Light. Stephen Hawkings great discovery was that the mysterious regions in space we call black holes radiate heat through quantum effects. Hawking has said that "black holes are not really black after all: they glow like a hot body, and the smaller they are, the more they glow. " Hawking's famous theory says that the temperature of a black hole varies inversely to its mass. The mathematician Louis Crane proposed a scifi-like scenario back in 1994 that billions of years in the future, after all the stars have burned out, that small black holes could be created to generate heat and guarantee survival of the species.

Confirming Hawking's theory, Tim Johannsen and Dimitrios Psaltis at the University of Arizona in Tucson calculate that black holes ought to be surrounded by a ring of light that comes from photons that have become trapped in a circular orbit about the black hole, just outside the event horizon, which are then scattered by gas and dust falling into the hole. NASA discovers brand new force of nature.

Could the Universe Be A Giant Quantum Computer? MIT scientist Seth Lloyd proposes that information is a quantifiable physical value, as much as mass or motion -that any physical system--a river, you, the universe--is a quantum mechanical computer. Lloyd has calculated that "a computer made up of all the energy in the entire known universe (that is, within the visible “horizon” of forty-two billion light-years) can store about 1092 bits of information and can perform 10105 computations/second.

" The universe itself is a quantum computer, he says, and it has made a mind-boggling 10122 computations since the Big Bang (for that part of the universe within the “horizon”). In Year Million: Science at the Far Edge of Knowledge, Leading and up-and-coming scientists and science writers cast their minds one million years into the future to imagine the fate of the human and/or extraterrestrial galaxy. First attempted by H. G. Lloyd has proposed that a black hole could serve as a quantum computer and data storage bank. 10 Strange Things About The Universe.

Space The universe can be a very strange place. While groundbreaking ideas such as quantum theory, relativity and even the Earth going around the Sun might be commonly accepted now, science still continues to show that the universe contains things you might find it difficult to believe, and even more difficult to get your head around. Theoretically, the lowest temperature that can be achieved is absolute zero, exactly ? 273.15°C, where the motion of all particles stops completely. One of the properties of a negative-energy vacuum is that light actually travels faster in it than it does in a normal vacuum, something that may one day allow people to travel faster than the speed of light in a kind of negative-energy vacuum bubble. One prediction of Einstein’s theory of general relativity is that when a large object moves, it drags the space-time around it, causing nearby objects to be pulled along as well.

Relativity of Simultaneity This is similar to arranging tiles evenly on a floor. January 6, 2011 - Fermi's Large Area Telescope Sees Surprising Flares in Crab Nebula. Menlo Park, Calif. —The Crab Nebula, one of our best-known and most stable neighbors in the winter sky, is shocking scientists with its propensity for fireworks—gamma-ray flares set off by the most energetic particles ever traced to a specific astronomical object. The discovery, reported today by scientists working with two orbiting telescopes, is leading researchers to rethink their ideas of how cosmic particles are accelerated. "We were dumbfounded," said Roger Blandford, who directs the Kavli Institute for Particle Astrophysics and Cosmology, jointly located at the Department of Energy's SLAC National Accelerator Laboratory and Stanford University. "It's an emblematic object," he said. The Crab Nebula, also known as M1, was the first astronomical object catalogued in 1771 by Charles Messier.

"It's a big deal historically," Blandford continued, "and we're making an amazing discovery about it. " Epic Discovery: Ancient Light from a Massive Black Hole Reveals New, Unknown History of Universe. Cambridge University astronomers have discovered the 'missing link' in the evolution of the universe following the Big Bang, it was claimed today.

For years scientists have known nothing about the 'dark ages' of space - a period between the Big Bang 13.7billion years ago and the creation of the first stars. But newly captured light emitted from a massive black hole has allowed scientists to peer into this unknown portion of the history of the universe. Astronomers discovered remnants of the first stars and evidence of the aftermath of an exploding star, which was a staggering 25 times larger than the sun.

Professor Max Pettini, of Cambridge's Institute of Astronomy, believes the discovery of these gases could help reveal the origins of the universe. "We have effectively been able to peer into the Dark Ages using the light emitted from a quasar. The light provides a backdrop against which any gas cloud in its path can be measured. So Close, yet So Far | Physical Review Focus. +Enlarge image Todd Mason, Mason Productions Inc. /LSST Corp. Observations of cosmic microwaves from 380,000 years after the big bang have been essential to modern cosmology, but cosmic neutrinos should carry information on the state of the universe when it was less than a second old. In the 23 October Physical Review Letters, a team points out a curious and hitherto ignored fact about these relic neutrinos: because of their masses, they travel more slowly than light does and actually originate from a much nearer region of the universe than the cosmic microwaves.

Although detecting cosmic neutrinos is still a long way off (if it’s possible at all), the work clarifies the type of information that, in theory at least, could be gleaned from relic neutrinos. Just after the big bang, the universe was a hot, seething soup of elementary particles constantly interacting with one another. –Michelangelo D'Agostino. An Ancient Subatomic Signature Extends Across the Universe: Relic Particles 10 Billion Light-Years in Length Discovered. An ancient subatomic signature extends across the universe. It seems that some subatomic particles, invisible and untouchable effects of the very creation of reality, might exist simultaneously across all of space.

"Relic" neutrinos, like the relic photons that make up the cosmic microwave background, are leftovers from the hot, dense early universe that prevailed 13.7 billion years ago. But over the lifetime of the cosmos, these relic neutrinos have been stretched out by the expansion of the universe, enlarging the range in which each neutrino can exist. Of course there's a little bit of physics involved when you talk about particles pouring out of the beginning of time. Neutrinos are tiny, almost undetectable neutral particles which stream through pretty much everything, ever. Over one hundred trillion have passed through you while reading this sentence.

The second part of this crash-course in cosmologically relevant physics is quantum theory. Scientists glimpse 'dark flow' lurking beyond the edge of the universe. There are already two giant cosmic mysteries, sources of hard-to-account for anti-gravity and gravity, called dark energy and dark matter, respectively, which are ubiquitous in the universe. In honour of this, and because the flow cannot be accounted for by the observed distribution of matter in the universe, the Nasa team that found the cosmic drift calls it "dark flow".

The find was made using data from Nasa's Wilkinson Microwave Anisotropy Probe (WMAP), which maps out changes (anisotropy) in the microwave (heat) radiation left over from the Big Bang 13.7 billion years ago, when the universe was born. This energy can be used to chart galaxy movements by measuring a minute shift of the microwave background's temperature, which astronomers call the "kinematic Sunyaev-Zel'dovich (SZ) effect. " The Nasa team, with colleagues at the University of California, Davis, University of Salamanca, Spain, and University of Hawaii, used this effect to track 700 clusters. The Universes of Max Tegmark. Is the Universe Actually Made of Math? | Math. Novikov self-consistency principle. The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity (solutions containing what are known as closed timelike curves).

The principle asserts that if an event exists that would give rise to a paradox, or to any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes. History of the principle[edit] Physicists have long been aware that there are solutions to the theory of general relativity which contain closed timelike curves, or CTCs—see for example the Gödel metric.

Novikov discussed the possibility of CTCs in books written in 1975 and 1983, offering the opinion that only self-consistent trips back in time would be permitted. Time loop logic[edit] Wheeler–Feynman absorber theory. The Wheeler–Feynman absorber theory (also called the Wheeler–Feynman time-symmetric theory) is an interpretation of electrodynamics derived from the assumption that the solutions of the electromagnetic field equations must be invariant under time-reversal symmetry, as are the field equations themselves. Indeed, there is no apparent reason for the time-reversal symmetry breaking which singles out a preferential time direction and thus makes a distinction between past and future.

A time-reversal invariant theory is more logical and elegant. Another key principle, resulting from this interpretation and reminiscent of Mach's principle due to Tetrode, is that elementary particles are not self-interacting. This immediately removes the problem of self-energies. This theory is named after its originators, the late physicists Richard Feynman and John Archibald Wheeler. T-symmetry and causality[edit] and point , which will arrive at point at the instant (here Then they observed that, if the relation T. Rotation.pdf (application/pdf Object) Comoving distance. Comoving coordinates[edit] While general relativity allows one to formulate the laws of physics using arbitrary coordinates, some coordinate choices are more natural (easier to work with).

Comoving coordinates are an example of such a natural coordinate choice. They assign constant spatial coordinate values to observers who perceive the universe as isotropic. Such observers are called "comoving" observers because they move along with the Hubble flow. A comoving observer is the only observer that will perceive the universe, including the cosmic microwave background radiation, to be isotropic. Non-comoving observers will see regions of the sky systematically blue-shifted or red-shifted. Thus isotropy, particularly isotropy of the cosmic microwave background radiation, defines a special local frame of reference called the comoving frame.

Most large lumps of matter, such as galaxies, are nearly comoving, so that their peculiar velocities (owing to gravitational attraction) are low. by where and. Intelligent Design of the Universe? or non-designed Multiverse? Physics Letters B : The holographic dark energy in non-flat Brans–Dicke cosmology. Black Hole Computers. Decoding the universe: how the new ... The Ultimate Laptop: A Black Hole. New York Times, September 5, 2000 By GEORGE JOHNSON For all the corporate enthusiasm over the unveiling of each new generation of computer chip (last month Intel announced that its Pentium 4 would be packed with 42 million transistors performing as many as 8.4 billion operations per second), consumers may be more apt to feel a sense of dread.

Once again the expensive desktop computers and laptops they were so proud of have become outmoded, destined to join the scrap piles of unsalable equipment accumulating in closets everywhere. Moore's law, which holds that computing power doubles approximately every 18 months, sometimes seems less a blessing than a curse. But the law cannot hold forever, and Dr. Seth Lloyd, an associate professor of mechanical engineering at the Massachusetts Institute of Technology, offers hope that the end is in sight. In a paper in the current issue of Nature, Dr. If that sounds like a rather dangerous device to hold on one's lap -- "Opening the lid," Dr. Thomas J. Black_Hole_Computers.pdf (application/pdf Object) Sun Professor Brian Cox on the highest energy explosion ever seen. Supersymmetry, Extra Dimensions and the Origin of Mass.

The Universe: Beyond the Big Bang. Why Our Universe Must Have Been Born Inside a Black Hole. “Accordingly, our own Universe may be the interior of a black hole existing in another universe.” So concludes Nikodem Poplawski at Indiana University in a remarkable paper about the nature of space and the origin of time. The idea that new universes can be created inside black holes and that our own may have originated in this way has been the raw fodder of science fiction for many years. But a proper scientific derivation of the notion has never emerged.

Today Poplawski provides such a derivation. He says the idea that black holes are the cosmic mothers of new universes is a natural consequence of a simple new assumption about the nature of spacetime. Poplawski points out that the standard derivation of general relativity takes no account of the intrinsic momentum of spin half particles. This predicts that particles with half integer spin should interact, generating a tiny repulsive force called torsion. That’s interesting for a number of reasons. This is a Big Bang type event.