Black holes might one day reverse course, turning into 'white holes' and start spewing out matter, according to scientists.
New papers published last week have attempted to figure out what goes on at the centre of a black hole. According to Albert Einstein's Theory of General Relativity, the centre of a black hole is a singularity - a point with no mass and infinite density.
"These predictions are not realistic because they disregard quantum effects," said Carlo Rovelli of the French Centre of Theoretical Physics.
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So using a new theory called loop quantum gravity - which combines Einstein's theories with quantum mechanics - scientists have tried to figure out what's actually going on.
According to the new papers, published in journals Physical Review Letters and Physical Review D, matter that falls into a black hole bounces right back out. It's just taking a very, very long time, because the extreme gravitational field at the centre of a black hole slows time right down.
"Because of the huge time distortion allowed by relativity, the time for the process to happen can be short - microseconds - when measured from inside the hole but long - billions of years - when measured from the outside," said Dr Rovelli.
One day, the scientists predict, everything that fell in will come back out.
"A white hole is the time-reversed image of a black hole: in it, matter can only move outwards."
At this point it's just a theory - but Dr Rovelli says it's one that would fill a number of holes in our current understanding of the universe.