Jo Marchant, consultant
How do you get rid of a black hole that's threatening to gobble the Earth? It could be as simple as popping it in a box and shooting it into space.
A handful of doomsayers have argued that the Large Hadron Collider particle accelerator at CERN
near Geneva, currently gearing up to start smashing protons
together this autumn, could produce Earth-destroying black holes
. Their concerns
were the main reason that the experiment's switch-on last year became the most widely-covered news story since pretty much ever.Physicists have dismissed the possibility
. But if it did happen (and there's a much
smaller chance than Walter Wagner hilariously gave it on the Daily Show
) there would be no need to panic: there is a plan to save us.
First, a bit of background. Certain theories involving the existence of extra dimensions do suggest that tiny black holes
could spring from the LHC's high-energy collisions, but it would take
the violation of some well-accepted physics principles for them to last
for more than the smallest fraction of a second.
physicists argue, cosmic rays strike particles in the Earth's
atmosphere all the time at higher energies than will be generated in
the LHC. The Earth is clearly still here, so either these collisions
don't make black holes, or if black holes are created, they're harmless.
are almost certainly right. But the whole point of the LHC is to
discover new physics, so it's impossible to rule out effects that
physicists haven't thought of. And the comparison with cosmic rays
isn't strictly analogous. Any black holes created by cosmic ray
collisions would be travelling at close to the speed of light, so
they'd zip straight through the Earth and out the other side before
they had the chance to cause any trouble. Any black holes produced by
the LHC would have close to zero momentum, so if they were stable,
they'd hang around much longer.
The chance of the LHC causing
any such problems is still incredibly tiny - we're more likely to all
be destroyed by an asteroid tomorrow. But that hasn't stopped a particle physicist
I was chatting to the other day from formulating a plan.
First, he pointed out that we'd have
plenty of time to act - the amount of energy produced in one of the
LHC's collisions would create a black hole with a
gravitational pull no more scary than that of an orange - not enough to suck any appreciable
matter towards it, so it would grow extremely slowly.
black holes can carry a charge, depending on the particles they gobble
up. So physicists could give the rogue hole a negative charge by firing
electrons at it from a cathode ray tube. Then they could trap it within
a box lined with negatively charged metal plates - the
negatively-charged black hole would be repelled by the negatively-charged walls, leaving it suspended inside. Making sure the
box otherwise contained a vacuum would stop the black hole from eating
any particles and getting any bigger. Then you could just load the box
onto a rocket, and shoot it out of the solar system.
that would be a pretty expensive mission to get rid of something that
would likely take billions of years to grow to Earth-swallowing size.
But why spoil the fun? With the CERN-based storyline
of Angels and Demons
already drawing mass audiences to the box office, black-hole catching
sounds like the perfect plot for Hollywood's next physics blockbuster.
(Image: The centre of the Milky Way, thought to be home to a black hole. Credit: Q D Wang et al / UMass Amherst / CXC / NASA)