Stephen Hawking Reith lecture: Mini black holes could provide world electricity demand
Stephen Hawking has said that mini black
holes could potentially provide enough energy to supply the world's electricity
demands – but could also destroy the planet. He made these comments as part of
the BBC's Reith lectures. The special series on black holes looks at the
physicist's ideas about these collapsed stars from which nothing can escape.
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Stephen Hawking |
In the latest talk – a full transcript of
which can be found here – Hawking said that 'mini' black holes, with the same
mass of a mountain, would give off enough electricity to power the planet.
"There
could be much smaller mini black holes with the mass of say, a mountain,"
he said. "A mountain-sized black hole would give off X-rays and gamma
rays, at a rate of about 10 million megawatts, enough to power the world's
electricity supply. It wouldn't be easy however, to harness a mini black hole.
You couldn't keep it in a power station, because it would drop through the
floor and end up at the centre of the Earth. If we had such a black hole, about
the only way to keep hold of it would be to have it in orbit around the Earth.
People have searched for mini black holes of this mass, but have so far not
found any. This is a pity, because if they had I would have got a Nobel Prize."
However, all is not lost, he said. Some
theories say we could a mini black hole on Earth with the extra dimensions of
space-time – where the universe we experience is a four-dimensional surface in
a 10-dimensional space, for example. He said the film Interstellar provided a
picture of this – the extra dimensions would not be visible because light would
not propagate through them. This suggests that we only see the four dimensions
of our universe.
"Gravity,
however, would affect the extra dimensions and would be much stronger than in
our universe. This would make it much easier to form a little black hole in the
extra dimensions. It might be possible to observe this at the LHC, the Large
Hadron Collider, at CERN in Switzerland. This consists of a circular tunnel, 27
kilometres [16.8 miles] long. Two beams of particles travel round this tunnel
in opposite directions, and are made to collide. Some of the collisions might
create micro black holes. These would radiate particles in a pattern that would
be easy to recognise. So I might get a Nobel Prize after all."
