Physicists have been working on an experiment in the laboratory that has to do with black holes. The experiment has confirmed that a prediction the late Stephen Haking made about black holes was correct. The black hole that the team created in their lab isn’t the same sort seen in space.
Black holes in space have such immense gravity that light can’t escape. The lab-made black hole was built using something called a Bose-Einstein condensate and its point of no return doesn’t prevent light from escaping, rather it prevents sound from escaping.
The Hawking theory that the team says its experiment verifies is called Hawking radiation. The team says that Hawking realized when trying to apply physical laws governing heat to black holes, the black hole must emit radiation from its surface. The challenge is that astronomers can’t see a black hole close enough to prove or disprove the theory. That impossibility has led scientists to create black hole analogs in labs.
This was done by trapping 8,000 rubidium atoms in a focused laser beam to create an elongated Bose-Einstein condensate. This is a system of ultra-cold atoms where strange quantum physical phenomena are visible on larger scales and are often used for this sort of experiment. A second laser increases the potential energy on one side of the condensate. A sharp transition separates the denser area, which is considered to be the outside of the black hole, and the less dense area is considered to be the inside of the black hole.
In one region of the experiment, sound is faster than the speed of the flow of the rubidium atoms, but on the other, the speed of sound is slower allowing the sound waves to only travel away from the sharp transition. This is how light behaves in a black hole. The team found that inside the event horizon of their lab-created black hole, the signal of Hawking radiation was a correlation between the sound waves both outside and inside of their black hole. One of the researchers says as he sees it, Hawking was correct.