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'Time Crystals' Could Upend Physicists' Theory of Time

'Time Crystals' Could Upend Physicists' Theory of Time
Physicists plan to create a “time crystal” — a theoretical object that moves in a repeating pattern without using energy — inside a device called an ion trap. Image: Hartmut Häffner In February 2012, the Nobel Prize-winning physicist Frank Wilczek decided to go public with a strange and, he worried, somewhat embarrassing idea. Impossible as it seemed, Wilczek had developed an apparent proof of “time crystals” — physical structures that move in a repeating pattern, like minute hands rounding clocks, without expending energy or ever winding down. Unlike clocks or any other known objects, time crystals derive their movement not from stored energy but from a break in the symmetry of time, enabling a special form of perpetual motion. “Most research in physics is continuations of things that have gone before,” said Wilczek, a professor at the Massachusetts Institute of Technology. Wilczek’s idea met with a muted response from physicists. A Crazy Concept The Big Test

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The Incredible Dark Matter Mystery: Why Astronomers Say it is Missing in Action Astronomers have a problem. Whenever they study the large scale structure of the universe, it soon becomes clear that the amount of visible matter cannot possibly generate enough gravity to hold together the structures they can see. Things like galaxy clusters and even galaxies themselves ought to fly apart given the amount of ordinary matter they contain. Something else must be holding these things together. So astronomers have dreamt up the idea of dark matter—mysterious, invisible and non-interacting stuff that fills the universe, generating the gravity necessary to hold everything together.

Controversially, Physicist Argues Time Is Real NEW YORK — Is time real, or the ultimate illusion? Most physicists would say the latter, but Lee Smolin challenges this orthodoxy in his new book, "Time Reborn" (Houghton Mifflin Harcourt, April 2013), which he discussed here Wednesday (April 24) at the Rubin Museum of Art. In a conversation with Duke University neuroscientist Warren Meck, theoretical physicist Smolin, who's based at Canada's Perimeter Institute for Theoretical Physics, argued for the controversial idea that time is real. "Time is paramount," he said, "and the experience we all have of reality being in the present moment is not an illusion, but the deepest clue we have to the fundamental nature of reality." [Album: The World's Most Beautiful Equations] Smolin said he hadn't come to this concept lightly.

Snobbish photons forced to pair up and get heavy Ordinarily, photons—particles of light—don't interact with each other. They interfere, but that's a characteristic that doesn't alter their wavelength or cause them to attract or repel. However, if photons can be induced to interact, it could open up a wide number of applications in quantum computing and optical materials. This sort of radical change can't happen under ordinary circumstances but is possible in special environments. Researchers fabricated just such a medium and produced photons that simultaneously act as though they are massive and mutually attractive. The key to this weird behavior involved passing light through a cold diffuse gas with strong inter-atomic interactions, properties that are usually exclusive but which can be induced in some circumstances.

Quantum Entanglement Could Stretch Across Time In the weird world of quantum physics, two linked particles can share a single fate, even when they’re miles apart. Now, two physicists have mathematically described how this spooky effect, called entanglement, could also bind particles across time. If their proposal can be tested, it could help process information in quantum computers and test physicists’ basic understanding of the universe. “You can send your quantum state into the future without traversing the middle time,” said quantum physicist S. Jay Olson of Australia’s University of Queensland, lead author of the new study. In ordinary entanglement, two particles (usually electrons or photons) are so intimately bound that they share one quantum state — spin, momentum and a host of other variables — between them.

A temperature below absolute zero Atoms at negative absolute temperature are the hottest systems in the world January 04, 2013 What is normal to most people in winter has so far been impossible in physics: a minus temperature. On the Celsius scale minus temperatures are only surprising in summer. 111, 033601 (2013): Stopped Light and Image Storage by Electromagnetically Induced Transparency up to the Regime of One Minute The maximal storage duration is an important benchmark for memories. In quantized media, storage times are typically limited due to stochastic interactions with the environment. Also, optical memories based on electromagnetically induced transparency (EIT) suffer strongly from such decoherent effects. External magnetic control fields may reduce decoherence and increase EIT storage times considerably but also lead to complicated multilevel structures.

Physicists Unveil World's Most Precise Clock (And a Twin to Compare It Against) Clocks are one of the enabling technologies of the modern world. Without highly accurate clocks, the global positioning system would not function correctly, neither would it be possible to synchronise networks over vast distances. And physicists rely on clocks to test the fundamental laws of the universe to ever deeper levels. So having more accurate and reliable clocks is an important goal. Today, Andrew Ludlow at the National Institute of Standards and Technology in Boulder and a few buddies unveil the two most accurate clocks ever built.

Tying Light in Knots [Slide Show] Knots can help unravel some knotty (sorry!) situations. The mathematical study of knotted shapes has proved constructive for many branches of physics, from understanding how fluids flow to developing quantum computers. Now physicists have found that light itself can be knotted by discovering a new set of solutions to the famous Maxwell equations of electromagnetism. In the 1860s Scottish physicist James Clerk Maxwell wrote down a series of equations describing how electric and magnetic fields form and change.

Controversial quantum computer aces entanglement tests - physics-math - 08 March 2013 Read full article Continue reading page |1|2 Editorial: "Quantum computers leap into the real world" A few days ago, I held a quantum computer in my hand – or did I? The niobium wafers I saw are the guts of the only commercially available quantum computer, but whether their calculations truly harness the weird world of quantum mechanics has provoked heated debate.