Apr 25, 2015 04:24 PM
http://fqxi.org/community/articles/display/201
EXCERPT: You’d have to go to extremes to carry out an experiment on a black hole: the nearest is thousands of light years away, and it’s not clear if you could ever get much information out of one. That’s a shame for physicists who would love to get their hands on one because it’s an arena in which gravity and quantum physics face off. But Sorin Paraoanu, a quantum physicist at the Aalto University School of Science in Finland, has come up with a way to custom-build a toy environment in his lab to test what happens when these two fundamental descriptions of reality collide. If Paraoanu succeeds, the result will be like "a lego game for theorists working on unifying gravity and quantum physics," he says.
[...] Doing any experiments in this regime is very difficult [...] One solution is to create an analog for gravity that is more powerful, and bends space-time more, than gravity itself. This ensures that the gravity analog will come into conflict with quantum rules in situations far less extreme than a black hole—involving less energy and a larger space. Paraoanu plans to do this using a "metamaterial" made from a chain of superconducting quantum interference devices (SQUIDs), each of which can be fine-tuned to precisely control how the material’s refractive index changes along its length. This is mathematically equivalent to changing the speed of light through the material or, in the context of building a gravity analog, changing the curvature of spacetime that light moves through. "In these analog systems we can be more efficient than real gravity," says Paraoanu. "We can bend spacetime as if we were near a black hole." Some popular models of quantum gravity propose that spacetime itself isn’t one classical continuum, but instead made up of quantized bits and pieces—and Paraoanu’s setup should be able to explore this notion....
EXCERPT: You’d have to go to extremes to carry out an experiment on a black hole: the nearest is thousands of light years away, and it’s not clear if you could ever get much information out of one. That’s a shame for physicists who would love to get their hands on one because it’s an arena in which gravity and quantum physics face off. But Sorin Paraoanu, a quantum physicist at the Aalto University School of Science in Finland, has come up with a way to custom-build a toy environment in his lab to test what happens when these two fundamental descriptions of reality collide. If Paraoanu succeeds, the result will be like "a lego game for theorists working on unifying gravity and quantum physics," he says.
[...] Doing any experiments in this regime is very difficult [...] One solution is to create an analog for gravity that is more powerful, and bends space-time more, than gravity itself. This ensures that the gravity analog will come into conflict with quantum rules in situations far less extreme than a black hole—involving less energy and a larger space. Paraoanu plans to do this using a "metamaterial" made from a chain of superconducting quantum interference devices (SQUIDs), each of which can be fine-tuned to precisely control how the material’s refractive index changes along its length. This is mathematically equivalent to changing the speed of light through the material or, in the context of building a gravity analog, changing the curvature of spacetime that light moves through. "In these analog systems we can be more efficient than real gravity," says Paraoanu. "We can bend spacetime as if we were near a black hole." Some popular models of quantum gravity propose that spacetime itself isn’t one classical continuum, but instead made up of quantized bits and pieces—and Paraoanu’s setup should be able to explore this notion....