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.
Meanwhile, up in Hanover, New Hampshire a bold team of researchers
at Dartmouth College propose a new way of creating a reproduction black
hole in the laboratory on a much-tinier scale than their celestial
counterparts. The new method to create a tiny quantum sized black hole
would allow researchers to better understand what physicist Stephen
Hawking proposed more than 35 years ago: black holes are not totally
void of activity; they emit photons, which is now known as Hawking
radiation.
“Hawking famously showed that black holes radiate
energy according to a thermal spectrum,” said Paul Nation, an author on
the paper and a graduate student at Dartmouth. “His calculations relied
on assumptions about the physics of ultra-high energies and quantum
gravity. Because we can’t yet take measurements from real black holes,
we need a way to recreate this phenomenon in the lab in order to study
it, to validate it.”
The researchers showed that a magnetic
field-pulsed microwave transmission line containing an array of
superconducting quantum interference devices, or SQUIDs, not only
reproduces physics analogous to that of a radiating black hole, but
does so in a system where the high energy and quantum mechanical
properties are well understood and can be directly controlled in the
laboratory.
“We can also manipulate the strength of the applied
magnetic field so that the SQUID array can be used to probe black hole
radiation beyond what was considered by Hawking,” said Miles Blencowe,
another author on the paper and a professor of physics and astronomy at
Dartmouth.
“In addition to being able to study analogue quantum
gravity effects, the new, SQUID-based proposal may be a more
straightforward method to detect the Hawking radiation,” says Blencowe.
Posted by Casey Kazan.
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Source: http://www.dartmouth.edu/~news/releases/2009/08/21a.html
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