Researchers propose new way to reproduce a black hole
August 21, 2009(PhysOrg.com) -- Despite their popularity in the science fiction genre, there is much to be learned about black holes, the mysterious regions in space once thought to be absent of light. In a paper published in the August 20 issue of Physical Review Letters Dartmouth researchers 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."
In this paper, the researchers show 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. The paper states, "Thus, in principle, this setup enables the exploration of analogue quantum gravitational effects."
"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.
This is not the first proposed imitation black hole, says Nation. Other proposed analogue schemes have considered using supersonic fluid flows, ultracold bose-einstein condensates and nonlinear fiber optic cables. However, the predicted Hawking radiation in these schemes is incredibly weak or otherwise masked by commonplace radiation due to unavoidable heating of the device, making the Hawking radiation very difficult to detect. "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.
More information: Phys. Rev. Lett. 103, 087004 (2009); DOI: 10.1103/PhysRevLett.103.087004
Source: Dartmouth College
1hour ago
Agreed.
Perhaps there's a technological solution on a quantum scale by which we can "tag" the matter-antimatter pair as it comes into existence, but I don't see it being a reality in the near future.
Funny we havnt heard much of the LHC lately perhaps they too now realise the danger.
It's like taking a million tons of TNT and setting it off and expecting to get the equivalent effect of a 1MT nuclear weapon going off in order to see what kind of radiation the TNT is emitting. You would probably turn around and say, "Wow, we always thought that nuclear weapons gave off lots of high energy radiation and particles, but this TNT explosion shows that they don't."
The collision energies produced by the LHC will be less than the energies of cosmic rays which have been colliding inside the Earth for billions of years. So if black holes are produced by such energies, they are too short-lived to matter.
HOWEVER... one has to wonder about LHC version 2.0 -- or 10.0. It is inevitable that humans will one day be capable of creating black holes large enough to eat matter faster than they evaporate. It should be interesting to see what will happen then. Humans have yet to resist creating anything which it is within our power to create ("some other country would just create it first!"). But perhaps technologies will also be developed to detect and eject black holes which accidentally fall into the Earth before they can do too much damage.
Assuming it's accidental.
To generate a tenth of a gee using flat deck plating would require the plating to have a density of about 240 metric tonnes per square centimeter.
If you collided with any normal spaceships, I doubt you'd even feel a bump. :-)
black holes were never thought to be "absent of light", there was a speculation that light could not escape their gravitational field.
but who needs editors, right?
Sounds like using a fluorescent lamp or even LED as an analogue for measuring the radiation of an incadescent lamp.
Those micro "black holes" will be created by smashing a few particles together, not by squashing a small star's worth of matter down infinitely. The "black holes" evaporate within microseconds, there is absolutely no chance of them destroying the world. I think the worst fear with the LHC is that they may never get the darn thing working..
Also - do you think these physicists would actually put the planet in danger by creating an actual black hole that could eat the planet? These guys base their entire lives on math and logic. They wouldn't create something that was extremely dangerous "just to see what happens".
...And don't bring up the Atomic Bomb. That was different.
'Twould be a safe ship, though, wouldn't it? All you little guys better never get in the way of my ship! :-)
"Clink!"
"Captain! Did you hear something?"
"It was probably nothing... As you were... Continue on course, all ahead full."