Event horizon tester

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From: http://www.telegraph.co.uk/earth/main.jhtm...scispace113.xml

Quote:Device mimics black hole event horizon

By Roger Highfield, Science Editor
Last Updated: 6:01pm GMT 13/02/2008

A team of researchers in Scotland has been able to boldly go where science fiction writers have only dreamt of visiting - inside the maw of a black hole, to crack some of the deepest mysteries of the cosmos.
# Nobel prize from a black hole?

Black holes, the remains of collapsed stars, are the most extraordinary objects in the universe, where the pull of gravity is so intense that light is sucked in if it strays beyond a boundary called the event horizon.

The device will enable Stephen Hawking's event horizon theories to be tested
The device will enable Stephen Hawking's event horizon theories to be tested

Now it seems these horizons can be mimicked using a table-top device that harnesses lasers to create an artificial black hole, according to a study by Prof Ulf Leonhardt of the University of St Andrews that could help win a Nobel prize for the world's best known physicist, Prof Stephen Hawking.

At St Andrews, Prof Leonhardt works on what are called quantum catastrophes, where so-called "singularities" can be created where the laws of wave physics are in danger of breaking down. Black holes are also singularities, where the pull of gravity is so intense that even light is sucked in.

The professor told the recent the Cosmology Meets Condensed Matter meeting in London that his team accomplished the feat of simulating key features of a black hole by firing lasers down an optical fibre, exploiting how different wavelengths of light move at different speeds within the fibre.

His team first shot a relatively slow moving laser pulse through the fibre, and then sent a faster "probe wave" chasing after it.
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The slower light pulse distorts the optical properties of the fibre, forcing the speedy probe wave to slow down dramatically when it catches up so it becomes trapped and can never overtake the pulse's leading edge, so that it acts in just the same way as a black hole event horizon, beyond which light cannot escape.

And the measurements by Prof Leonhardt, Dr Chris Kuklewicz and Dr Friedrich Koenig at St Andrews, with Dr Thomas Philbin of the University of Erlangen, agree with the predictions of cosmologists, who have already worked out exactly how light should change frequency as it approaches an event horizon - from both the outside or the inside of a black hole.

Prof Hawking's chance of winning the Nobel prize has improved markedly because this device makes it possible to test his theories, which make specific predictions about the event horizon - the rim of a black hole.

"We show by theoretical calculations that such a system is capable of probing the quantum effects of horizons, in particular Hawking radiation," say the St Andrews team in a preprint of their paper.

Prof Hawking predicts that radiation would be given off at the horizon of black holes so that they would evaporate. In his book, The Universe in a Nutshell, the Cambridge University physicist said that only smaller black holes give off enough "Hawking radiation" to be detectable and there do not seem to be many of them around. "That is a pity. If one were discovered, I would get a Nobel prize."

Prof Ray Rivers at Imperial College London tells New Scientist: "They've done some clever stuff to give us a chance of seeing Hawking radiation for the first time."

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