Respected physicist Stephen Hawking has just dropped a major bombshell: There may be no such thing as black holes as we know them.
This belief would be eagerly dismissed should it have come from anyone else, but when Hawking speaks out on the matter, it may open the door to a serious debate.
Where does Hawking's belief come from? In a paper posted online, Hawking dismisses the idea of an event horizon. Event horizons are the point beyond which nothing can escape being trapped in a black hole, including light.
Hawking told Nature,
“There is no escape from a black hole in classical theory." However, quantum theory, "enables energy and information to escape from a black hole". But an alternative to the theory isn't exactly easy to mesh out. Hawking admits that theorists are trying to reconcile gravity and with other "fundamental forces of nature".
Okay, so there are no event horizons and black holes as we understand them are way off. What are the alternatives?
Hawking in his paper proposed the existence of "apparent horizons". Unlike an event horizon, an apparent horizon does hold onto energy, but it eventually releases it.
The decision to re-examine black holes and event horizons was caused by the so-called black hole/firewall paradox. a mind bending conundrum introduced by Joseph Polchinski of the Kavli Institute and his team. They made calculations that suggested that if a person were to encounter and be sucked into a black hole, rather than merely being stretched like "a string of spaghetti" the individual would pass through a firewall and be burned to a crisp. This was a case of a scenario agreeing with quantum mechanics but disagreeing with Einstein's theory of relativity.
Hawking's alternative suggests that there is no event horizon around a black hole, therefore nothing to "catch fire". But some wonder that even with the omission of an event horizon would be enough to make the various aspects of quantum physics agree in this particular scenario.
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