Image courtesy NASA/CXC/CfA/R.Kraft et al., MPIfR/ESO/APEX/A.Weiss et al. and ESO/WFI
Published April 9, 2010
In turn, all the black holes found so far in our universe—from the microscopic to the supermassive—may be doorways into alternate realities.
According to a mind-bending new theory, a black hole is actually a tunnel between universes—a type of wormhole. The matter the black hole attracts doesn't collapse into a single point, as has been predicted, but rather gushes out a "white hole" at the other end of the black one, the theory goes.
In a recent paper published in the journal Physics Letters B, Indiana University physicist Nikodem Poplawski presents new mathematical models of the spiraling motion of matter falling into a black hole. His equations suggest such wormholes are viable alternatives to the "space-time singularities" that Albert Einstein predicted to be at the centers of black holes.
According to Einstein's equations for general relativity, singularities are created whenever matter in a given region gets too dense, as would happen at the ultradense heart of a black hole.
Einstein's theory suggests singularities take up no space, are infinitely dense, and are infinitely hot—a concept supported by numerous lines of indirect evidence but still so outlandish that many scientists find it hard to accept.
If Poplawski is correct, they may no longer have to.
According to the new equations, the matter black holes absorb and seemingly destroy is actually expelled and becomes the building blocks for galaxies, stars, and planets in another reality.
Wormholes Solve Big Bang Mystery?
The notion of black holes as wormholes could explain certain mysteries in modern cosmology, Poplawski said.
For example, the big bang theory says the universe started as a singularity. But scientists have no satisfying explanation for how such a singularity might have formed in the first place.
If our universe was birthed by a white hole instead of a singularity, Poplawski said, "it would solve this problem of black hole singularities and also the big bang singularity."
Wormholes might also explain gamma ray bursts, the second most powerful explosions in the universe after the big bang.
Gamma ray bursts occur at the fringes of the known universe. They appear to be associated with supernovae, or star explosions, in faraway galaxies, but their exact sources are a mystery. (Related: "Gamma-Ray Burst Caused Mass Extinction?")
Poplawski proposes that the bursts may be discharges of matter from alternate universes. The matter, he says, might be escaping into our universe through supermassive black holes—wormholes—at the hearts of those galaxies, though it's not clear how that would be possible.
"It's kind of a crazy idea, but who knows?" he said. (Related: "Are Wormholes Tunnels for Time Travel?")
There is at least one way to test Poplawski's theory: Some of our universe's black holes rotate, and if our universe was born inside a similarly revolving black hole, then our universe should have inherited the parent object's rotation.
If future experiments reveal that our universe appears to rotate in a preferred direction, it would be indirect evidence supporting his wormhole theory, Poplawski said.
Wormholes Are "Exotic Matter" Makers?
The wormhole theory may also help explain why certain features of our universe deviate from what theory predicts, according to physicists.
Based on the standard model of physics, after the big bang the curvature of the universe should have increased over time so that now—13.7 billion years later—we should seem to be sitting on the surface of a closed, spherical universe.
But observations show the universe appears flat in all directions.
What's more, data on light from the very early universe show that everything just after the big bang was a fairly uniform temperature.
That would mean that the farthest objects we see on opposite horizons of the universe were once close enough to interact and come to equilibrium, like molecules of gas in a sealed chamber.
Again, observations don't match predictions, because the objects farthest from each other in the known universe are so far apart that the time it would take to travel between them at the speed of light exceeds the age of the universe.
To explain the discrepancies, astronomers devised the concept of inflation.
Inflation states that shortly after the universe was created, it experienced a rapid growth spurt during which space itself expanded at faster-than-light speeds. The expansion stretched the universe from a size smaller than an atom to astronomical proportions in a fraction of a second.
The universe therefore appears flat, because the sphere we're sitting on is extremely large from our viewpoint—just as the sphere of Earth seems flat to someone standing in a field.
Inflation also explains how objects so far away from each other might have once been close enough to interact.
But—assuming inflation is real—astronomers have always been at pains to explain what caused it. That's where the new wormhole theory comes in.
According to Poplawski, some theories of inflation say the event was caused by "exotic matter," a theoretical substance that differs from normal matter, in part because it is repelled rather than attracted by gravity.
Based on his equations, Poplawski thinks such exotic matter might have been created when some of the first massive stars collapsed and became wormholes.
"There may be some relationship between the exotic matter that forms wormholes and the exotic matter that triggered inflation," he said.
Wormhole Equations an "Actual Solution"
The new model isn't the first to propose that other universes exist inside black holes. Damien Easson, a theoretical physicist at Arizona State University, has made the speculation in previous studies.
"What is new here is an actual wormhole solution in general relativity that acts as the passage from the exterior black hole to the new interior universe," said Easson, who was not involved in the new study.
"In our paper, we just speculated that such a solution could exist, but Poplawski has found an actual solution," said Easson, referring to Poplawski's equations.
Nevertheless, the idea is still very speculative, Easson said in an email.
"Is the idea possible? Yes. Is the scenario likely? I have no idea. But it is certainly an interesting possibility."
Future work in quantum gravity—the study of gravity at the subatomic level—could refine the equations and potentially support or disprove Poplawski's theory, Easson said.
Wormhole Theory No Breakthrough
Overall, the wormhole theory is interesting, but not a breakthrough in explaining the origins of our universe, said Andreas Albrecht, a physicist at the University of California, Davis, who was also not involved in the new study.
By saying our universe was created by a gush of matter from a parent universe, the theory simply shifts the original creation event into an alternate reality.
In other words, it doesn't explain how the parent universe came to be or why it has the properties it has—properties our universe presumably inherited.
"There're really some pressing problems we're trying to solve, and it's not clear that any of this is offering a way forward with that," he said.
Still, Albrecht doesn't find the idea of universe-bridging wormholes any stranger than the idea of black hole singularities, and he cautions against dismissing the new theory just because it sounds a little out there.
"Everything people ask in this business is pretty weird," he said. "You can't say the less weird [idea] is going to win, because that's not the way it's been, by any means."
One big problem... If the energy being amassed at the point of entry (or theoretical point of existence) of the black hole is so great that it collapses the energy into itself, then that energy may not be destroyed as much as equalized as all of the elements of energy are combined. Although we may not have only positive and negative to contend with, the multitude of other forces (lets call them neutral and maelstrom) that enter and combine with the known energy elements commingle and coalesce into another form of that energy at a different level. I contend that at that point, it does become another level (level up) of energy, and is for the most part, stored until there is and imbalance. And, until that imbalance evens out or catastrophically falls to one side, the black hole drags into itself all things possible to either a point of rebalance or the event horizon of something catastrophic, it releases the gamma bursts.
My summation is that the ‘black hole’ is nothing more than a gas tank, and until it reaches a critical mass of this leveled up material, it keeps filling up.
I believe that both Mr.Marlow and Mr. Wang are correct to some degree.
Mr. Marlow points out that the escape velocity might be somewhat constant to c, that itself could be a coincidence... but then again, it is not exact (nor will it ever be as the energy diverted and portioned off from entering the black hole would cause a dispensation to the black hole and the alternate universe at an unfair equation [we don't know the veriables]), so it therefore is only something close to c and not true to being a parent speed, only something relative.
Mr. Wang is even closer if you think about your shower drain taking in too much water, once the optimum volume has occurred, you get a back pressure (or lack of vacuum) and for a moment, an equilibrium, which allows a gamma burst to occur as the burst is too much for the black hole to contain.
Take 200 billion galaxies in the universe with 200 billion suns each and you get a mass of the universe of about 8x10^52 kg. Take that mass and a radius of 1.3x10^26 m (14 b.l.y.) and you get an escape velocity equal to something close to c. If the escape velocity really is c this mean that our own universe is a black hole and other black holes should be the same as ours - another universe.
Although this is an interesting theory there is a slight problem to it. (Two in fact) There can not be an object that sucks in everything, yet does not release anything. The worm-hole solves that rather nicely. However, if a worm-hole were to ever exist, it would have a very high chance of being unstable and would implode on itself with a slight disturbance, such as the disturbance of matter flowing though it. Another way to solve the matter of not releasing any energy would be the fact that a white-hole (the complete opposite of a black hole) existed. However, a white-hole would be almost impossible to create as black-holes are almost impossible to destroy.
Sorry if I had any outdated info or incorrect. It's been a while.
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