Planets, maybe even advanced life, could theoretically exist inside a black hole according to a new theory, reports the Discovery.
The idea, by physicist Professor Vyacheslav Dokuchaev from the Institute for Nuclear Research of the Russian Academy of Sciences in Moscow, appears to go against the common belief that black holes are giant gravity wells gobbling up anything that gets too close.
Dokuchaev says that some black holes have a complex internal structure that allows photons, particles and planets to orbit a central singularity, according to one scientist. A singularity is the region in a black hole when space and time become infinite.
In his paper, written for the journal Journal of Cosmology and Astroparticle Physics, he claims that at the centre of certain black holes, and under the right conditions, is an area where the fabric of space and time exists once more.
A black hole is surrounded by the event horizon, a region beyond which objects need to travel faster than the speed of light to escape the black hole. Because nothing can theoretically travel faster than the speed of light, nothing escapes once it’s passed the event horizon.
In his paper, Dokuchaev studies hypothetical orbits in the area between the event horizon and the singularity to understand their dynamics.
He says while conventional orbits wouldn’t be possible, there are some places where particles and planets could have stable though unusual spiral orbits.
Dokuchaev calculates, such a planet would be brightly illuminated by the singularity and by photons trapped in the same orbit. He even speculates that these conditions could prove self-sufficient for alien life.
“This planet might even support a complex chemistry rich enough to allow life to evolve”, says Dokuchaev. “Advanced civilisations may live safely inside the black hole without being visible from the outside”.
Dokuchaev admits such a civilisation would have to cope with extraordinary conditions including huge tidal forces and massive energy densities as photons become trapped. And he admits there’s also the problem of causality violations, where the rules of space-time don’t apply.
Astronomer Dr David Floyd from the Australian Astronomical Observatory and the University of Melbourne says even if the theory is correct, it would be impossible to know what is occurring beyond the event horizon of a black hole.
“At this point – and perhaps forever – we’re restricted to making untestable assertions,” says Floyd. “As far as we know, matter would go into free fall, that is, it would all fall into this tiny infinitesimal point at the centre which forms the singularity.”
Floyd says one shortcoming of the paper is that it assumes radiation has no impact on orbits inside the black hole. “It wouldn’t take much to produce drag which would slow down the orbits described in Dokuchaev paper, causing them to collapse onto the singularity”.
But Floyd admits it opens up some interesting philosophical questions. “Given the number of black holes in the universe – lots – one might infer that life is inevitable inside at least one of them if there really are stable orbits,” he says. “Maybe there are entire universes inside black holes.”
Earlier this year, scientists discovered that the black hole M87 is almost twice as big as had previously been thought. It was observed in M87, by far the largest and most distant galaxy some 50 million light years away.
Researchers said that it may have formed as a result of hundreds of smaller black holes merging into one at some point in the past. As a point of comparison, the black hole at the centre of the Milky Way is 1,000 times smaller. [via Daily Mail (UK), ABC News (AU) and Discovery]