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Explaining Stephen Hawking's New Theory On Black Holes

Graphic image of a black hole and a normal star.
Jerry Orosz
Graphic image of a black hole and a normal star.
Explaining Stephen Hawking's New Theory On Black Holes

Stephen Hawking, a pioneer in our modern understanding of black-holes, revised his theory on what happens when a star explodes and collapses on itself in a provocative paper published last week.

Jerry Orosz, an associate professor of astronomy at San Diego State University, explains how Hawking's new theory, if true, changes what we know about black holes.

"A black hole is a region of space where the density of matter is so high that nothing escapes, not even light and so the gravitational pull is just too strong for anything to get out," Orosz said.


He said lately physicists have been trying to merge the theory of quantum mechanics with the theory of general relativity.

Based on new calculations of particle on the edge of a black hole, Hawking said in the PBS documentary "Hawking", "Some particles could escape the black hole, which seemed to make a mockery of the known laws of physics."

At the heart of this new theory, Orosz said, is an imaginary boundary called the event horizon.

"It's the boundary beyond which you cannot escape," Orosz said. "If you're outside the event horizon, in principle you can escape if you go fast enough and once you cross the event horizon you're stuck."

Orosz said Hawking's new theory suggests some matter might be able to escape the event horizon.


"There might be some possibility the matter can be hanging around what he calls sort of an apparent horizon just inside," Orosz said. "And the information can eventually get out but possibly not in a useful form."

Orosz said, understanding black holes is important because they represent the "most extreme states of gravity."

"Understand those and you've really made progress," he said.

Orosz said, determining whether Hawking's theory is correct will be a difficult question to answer.

"At least in the very near future," he said.