If you ever fell into a black hole, your body would likely get ripped into shreds and ‘spaghettified’.
At least that’s the theory put forward by most physicists today.
But a new study is challenging that claim by suggesting there may be some black holes that you could survive – although doing so may put you into a strange reality.
These black holes would destroy your past life and trap you in a parallel universe with an infinite number of possible futures.
This is because the universe on the other side would not be governed by the rules of cause and effect that apply in ours.
As a result you could ‘live forever’, researchers claim.
A mathematician made the discovery after crunching the numbers on a particular type of black hole with an electrical charge, called a Reissner-Nordström-de Sitter black holes (artist’s impression)
A mathematician from the University of California, Berkeley, made the discovery after crunching the numbers on a particular type of black hole with an electrical charge.
In the real world, your past determines your future and this determinism rules the laws of physics.
This means that the physical laws of the universe do not allow for more than one possible future.
If a scientist knew exactly how the universe began, they could theoretically calculate what will happen for the rest of time and all of space.
UC Berkeley postdoctoral fellow Peter Hintz found that, for something known as ‘Reissner-Nordström-de Sitter’ black holes, this determinism does not apply.
If a space traveller were able to venture into one of these relatively benign black holes, they may be able to survive the experience.
This would give them passage from our deterministic world into a non-deterministic black hole and, in theory, out the other side.
If they were able to avoid the black hole’s infinitely dense singularity, they could emerge into another universe on the other side.
If a space traveller were able to venture into one of these relatively benign black holes, they may be able to survive the experience. The graphic shows a space-time diagram of the gravitational collapse of a charged spherical star to form a charged black hole
What would happen next is unknown, as in a non-deterministic universe the relationship between cause and effect would no longer exist.
Any and every outcome of everything that is, was and will be possible could exist at the same time.
This strange phenomenon is a quirk of Albert Einstein’s general theory of relativity which, for the past century, has been the standard model used to explain the way gravity works.
‘Normally in physics, initial conditions and the laws of physics are supposed to fully determine what happens to any physical system,’ said Robert Mann, Professor of physics and applied mathematics at the University of Waterloo, Canada, who was not involved with the study.
WHAT ARE BLACK HOLES?
Black holes are strange objects in the universe that get their name from the fact that nothing can escape their gravity, not even light.
If you venture too close and cross the so-called event horizon, the point from which no light can escape, you will also be trapped or destroyed.
For small black holes, you would never survive such a close approach anyway.
The tidal forces close to the event horizon are enough to stretch any matter until it’s just a string of atoms, in a process physicists call ‘spaghettification’.
But for large black holes, like the supermassive objects at the cores of galaxies like the Milky Way, which weigh tens of millions if not billions of times the mass of a star, crossing the event horizon would be uneventful.
Because it should be possible to survive the transition from our world to the black hole world, physicists and mathematicians have long wondered what that world would look like.
They have turned to Einstein’s equations of general relativity to predict the world inside a black hole.
These equations work well until an observer reaches the centre or singularity, where, in theoretical calculations, the curvature of space-time becomes infinite.
‘However general relativity doesn’t have this feature, curiously enough.
‘If I give you an initial distribution of matter and energy over the entire universe, the equations of general relativity in general will not predict the entire future of the space-time.’
Professor Hintz studied a specific type of non-rotating black hole, which have a so-called Cauchy horizon within their event horizon.
WHAT IS EINSTEIN’S GENERAL THEORY OF RELATIVITY?
Albert Einstein (pictured) published his General Theory of Relativity in 1915
In 1905, Albert Einstein determined that the laws of physics are the same for all non-accelerating observers, and that the speed of light in a vacuum was independent of the motion of all observers – known as the theory of special relativity.
This groundbreaking work introduced a new framework for all of physics, and proposed new concepts of space and time.
He then spent 10 years trying to include acceleration in the theory, finally publishing his theory of general relativity in 1915.
This determined that massive objects cause a distortion in space-time, which is felt as gravity.
At its simplest, it can be thought of as a giant rubber sheet with a bowling ball in the centre.
Pictured is the original historical documents related to Einstein’s prediction of the existence of gravitational waves, shown at the Hebrew university in Jerusalem
As the ball warps the sheet, a planet bends the fabric of space-time, creating the force that we feel as gravity.
Any object that comes near to the body falls towards it because of the effect.
Einstein predicted that if two massive bodies came together it would create such a huge ripple in space time that it should be detectable on Earth.
It was most recently demonstrated in the hit film film Interstellar.
In a segment that saw the crew visit a planet which fell within the gravitational grasp of a huge black hole, the event caused time to slow down massively.
Crew members on the planet barely aged while those on the ship were decades older on their return.
Black holes (artists’s impression) are thought to be regions of space so dense that they trap or even destroy all matter, but a new study suggests that visiting one might just be possible. Experts theorised that crossing the threshold of one is not as impossible as was thought
The Cauchy horizon is the spot where determinism breaks down, where the past no longer determines the future.
Physicists have argued that no observer could ever pass through the Cauchy horizon point because they would be annihilated.
As an observer approaches the Cauchy horizon time slows down, since clocks tick slower in a strong gravitational field, they argue.
As light, gravitational waves and anything else encountering the black hole fall inevitably toward the Cauchy horizon, an observer also falling inward would eventually see all this energy barrelling in on them at the same time.
In effect, all the energy the black hole sees over the lifetime of the universe would hit the Cauchy horizon at the same time, blasting into oblivion any observer who made it that far.
Dr Hintz’s calculations uncovered an exception to this rule with Reissner-Nordström-de Sitter black holes.
In a written statement, he said: ‘No physicist is going to travel into a black hole and measure it. This is a math question.
‘But from that point of view, this makes Einstein’s equations mathematically more interesting.
‘This is a question one can really only study mathematically, but it has physical, almost philosophical implications, which makes it very cool.
The downside to this voyage is that it would destroy your past life and trap you in a parallel universe with an infinite number of possible futures. This image show’s an artist’s impression of a black hole scientists expect to observe in 2018
‘There are some exact solutions of Einstein’s equations that are perfectly smooth, with no kinks, no tidal forces going to infinity, where everything is perfectly well behaved up to this Cauchy horizon and beyond. After that, all bets are off.’
Dr Hintz’s equations only work because the universe is expanding at an increasing rate.
Because space-time is being increasingly pulled apart, much of the universe on the other side of the black hole will not affect it at all.
As energy can’t travel faster than the speed of light, only matter and energy which is within the black hole’s observable horizon will be pulled in over its lifetime.
In this scenario, the expansion of the universe would counteract the amplification caused by time dilation inside the black hole that would appear to cause all matter to hit the observer in one go.
For certain situations, such as inReissner-Nordström-de Sitter black holes, this stretching of space-time would cancel the time dilation entirely, allowing a traveller to pass through unharmed.
The full findings of the study were published in the journal Physical Review Letters.