Mark Megahan
Everyone knows about black holes but there are theoretical white ones which nobody knows how to find. Astrophysicists spend their entire lives trying to unscrew the inscrutable and when the math doesn’t add up the way they expect it to, it really drives them nuts. The elusive unicorn they’re chasing would look a lot like a mini-big bang. If another universe did a gnab gib crunch, our universe could have been blasted out the other side in a new dimension. That’s what the numbers suggest.
Mirror image white holes
Einstein said white holes should be as common as black ones but he never mentioned either one. Both are buried as solutions based on his equations.
Theoretical physicist Carlo Rovelli at the Centre de Physique Théorique in France is working on something like a looking-glass universe in the mirror of this one. Both varieties should be opposite faces of the same coin.
White holes, astronomers note, are camouflaged because “a white hole looks exactly like a black hole. It has mass. It might spin. A ring of dust and gas could gather around the event horizon.”
While both of them have a point of no return boundary surrounding their bubble of space-time, the white variety will burp.
The problem, which makes white holes so hard to find, is that unlike the black variety, which stick around and keep getting bigger, these are more like a popping pimple. Everything comes out all at once. It then hangs around in space, but not for long.
“It’s only in the moment when things come out that you can say, ‘ah, this is a white hole,‘” Professor Rovelli explains. “Any outgoing matter would collide with the matter in orbit, and the system would collapse into a black hole.”
Black hole reversed in time
If you were to video a black hole then run the film backwards, it would show a white hole in action. The event horizon on a black hole is the “sphere of no return.” For white holes, that same boundary is one where nothing is ever getting in.
“Space-time’s most exclusive club.” Karl Schwarzschild was the one who did all the math, back in 1916 only a year after Albert Einstein unleashed Relativity on the world.
It wasn’t until 1960 when mathematician Martin David Kruskal “extended Schwarzchild’s black hole description.” He noticed that buried in the equations was a lurking monster.
“His new picture contained a reflection of the black hole singularity, although he didn’t realized its significance at the time.” Nobody started talking about black holes until Stephen Hawking came around and that’s when the mirror-image twin picked up the name white hole.
While he keeps inching closer to a solution, it remains just beyond his grasp. “How does a black hole die? We don’t know. How is a white hole born? Maybe a white hole is the death of black hole,” Rovelli shrugs. “The two questions join nicely, but you have to violate the general relativity equations in the passage from one to the other.”
He keeps hunting white holes because “the Big Bang’s explosion of matter and energy looks like potential white hole behavior.” To Hal Haggard, a theoretical physicist at Bard College in New York, “the geometry is very similar in the two cases. Even to the point of being mathematically identical at times.“
