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Posted by Trayan
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Source: NewScientist
Учени успяха да надминат скоростта на светлината!
IT'S a speed record that is supposed to be impossible to break. Yet two physicists are now claiming they have propelled photons faster than the speed of light.
This would be in direct violation of a key tenet of Einstein's special
theory of relativity that states that nothing, under any circumstance,
can exceed the speed of light.
Günter Nimtz and Alfons
Stahlhofen of the University of Koblenz, Germany, have been exploring a
phenomenon in quantum optics called photon tunnelling, which occurs
when a particle slips across an apparently uncrossable barrier. The
pair say they have now tunnelled photons "instantaneously" across a
barrier of various sizes, from a few millimetres up to a metre. Their
conclusion is that the photons traverse the barrier much faster than
the speed of light.
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Posted by chshkt
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Lene Hau has already shaken scientists' beliefs about the nature of
things. Albert Einstein and just about every other physicist insisted
that light travels 186,000 miles a second in free space, and that it
can't be speeded-up or slowed down. But in 1998, Hau, for the first
time in history, slowed light to 38 miles an hour, about the speed of
rush-hour traffic.
Two years later, she brought light to a complete halt in a cloud of
ultracold atoms. Next, she restarted the stalled light without changing
any of its characteristics, and sent it on its way. These highly
successful experiments brought her a tenured professorship at Harvard
University and a $500,000 MacArthur Foundation award to spend as she
pleased.
Now Mallinckrodt Professor of Physics and of Applied Physics, Hau
has done it again. She and her team made a light pulse disappear from
one cold cloud then retrieved it from another cloud nearby. In the
process, light was converted into matter then back into light. For the
first time in history, this gives science a way to control light with
matter and vice versa.
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Posted by Julia
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 According to the Standard Model of particles and forces, the Higgs mechanism gives mass to particles. Measuring the mass of the top quark and the mass of the W boson, scientists can restrict the allowable mass range of the not-yet-observed Higgs boson. (Image courtesy of Fermilab)
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University of Toronto researchers are now closer to answering contemporary physics' most pressing question: where is the missing particle that gives matter mass, known as Higgs-boson? The breakthrough comes after researchers discovered that the mass of another subatomic particle -- the W boson -- is slightly heavier than previous measurements, pointing them in a new direction...
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