Two new papers say everything we knew about black holes was wrong.
Black holes are undoubtedly weird enough to imagine but two
recent papers say we don’t understand how they work at all. They go against the
previous theories that predicted the center of a black hole to feature a point
of infinite density called a singularity. Instead, say the new papers, matter
might be sucked into black holes and spat out later in the future somewhere
else across the Universe.
Black holes are undoubtedly weird enough to imagine but two
recent papers say we don’t understand how they work at all. They go against the
previous theories that predicted the center of a black hole to feature a point
of infinite density called a singularity. Instead, say the new papers, matter
might be sucked into black holes and spat out later in the future somewhere
else across the Universe.
The papers were authored by the team of Abhay Ashtekar andJavier Olmedo at Pennsylvania State University and Parampreet Singh at
Louisiana State University, who applied the theory of loop quantum gravity to
black holes to find that they do not have singularities in the middle.
Loop quantum gravity describes the fabric of spacetime as “a
lattice of spin networks, which evolve over time,” explains University of Notre
Dame physics professor Don Lincoln, who is also the senior scientist at the
Fermi National Accelerator Laboratory. More specifically, loop quantum gravity
maintains that “spacetime is quantized, with a smallest possible unit or piece
of space and time, beyond which spacetime cannot be subdivided further,” says
Lincoln.
The scientists calculated that the strong curving of
spacetime near a black hole’s center results in the spacetime actually
extending into an area in the future structured like a white hole, which is
like a black hole in reverse, spurting matter out rather than pulling it in.
Another way to think about this is that because time near
the center of a black hole is very slowed down (due to confronting the
strongest gravitational field in the Universe), matter that falls into a black
hole doesn’t actually disappear – but gets shot back out around the universe
some time later. So if you fast-forwarded way into the future, you’d find this
black hole pushing the matter out.
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Artist rendering of the black-to-white-hole transition.
Credit: Ashtekar, Olmedo, and Singh. |
While these ideas are not easily testable, “it is not
implausible that empirical observations could support this scenario,” says Carlo
Rovelli from the Center of Theoretical Physics at the Aix-Marseille University
and Toulon University in Marseille, France, upon reviewing the new research.
Don Lincoln also points out that one possibility is that the
observed phenomenon of “fast radio bursts” could could be explained as a
signature of a black hole transforming into a white hole. Similarly telling
could be the detection of very high energy cosmic rays in the Earth’s
atmosphere.