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  • Longtime viewers of this channel know that we talk about black holes a lot.

  • We just can’t seem to get enough of them.

  • We give them so much attention but today were going to talk about their bizarro twins, white

  • holes.

  • Basically, a white hole is the hypothetical opposite of a black hole.

  • Now I’d bet that you know what a black hole is, but hey, they still have to explain seat

  • belts every time you fly on an airplane, so buckle up because after the refresher were

  • going on a wild ride.

  • Black holes are regions of space where so much mass is packed together so densely it

  • forms what’s called a singularity, and nothing can move fast enough to escape its gravitational

  • pull.

  • Not even the fastest thing in the universe, light, can escape its clutches.

  • But you knew that right?

  • Everybody knows what a black hole isexcept that nobody knows what a black hole is, not

  • exactly anyway.

  • Because of that pesky fact that light can’t escape, we can’t see what’s going on inside

  • a black hole.

  • So we have to rely on theories and equations to deduce what’s happening at the center

  • of the event horizon, and that has been a major sticking point in physics.

  • There are two competing explanations to describe black holes.

  • One of them is Einstein’s theory of general relativity, where the mass of a black hole

  • bends spacetime so much that it becomes one single point of infinite density.

  • On the other hand, according to quantum mechanics there can’t be an infinitely small point.

  • It can be very very small, but not infinitely so.

  • And this irreconcilable difference is one of the greatest debates in physics, since

  • general relativity is our best description of gravity, while quantum mechanics has been

  • called the most successful theory ever.

  • But some physicists believe white holes could  square these two predictions and reveal what’s

  • happening inside a black hole.

  • The equations of general relativity allow for the possibility of white holes, all you

  • have to do is set the mass of the singularity to zero and everything gets turned on its

  • ear.

  • Instead of a cosmic vacuum that sucks up everything that strays too close, you get a… whatever

  • the opposite of a vacuum is?

  • I’m not good with metaphors, but the point is all it can do is spew stuff out.

  • But then the question is, how do you get a singularity, a point of infinite density remember,

  • with no mass?

  • And how does a massless singularity spit anything out?

  • Because of that head scratcher white holes have long been written off as a mathematical

  • quirk but not something that can happen in reality.

  • However, quantum mechanics allows for someadjustmentsto the solutions of the

  • equations of general relativity, and with those adjustments, the interior of a black

  • hole could transform into a white hole.

  • One physicist describes it as though the curved spacetime of the black hole itself is bouncing

  • out again, and this rebound opens up some tantalizing possibilities.

  • Since a black hole might transform into a white hole, that means things falling into

  • it may come out again.

  • This would solve another issue quantum physics has with black holes because in quantum physics

  • information cannot be destroyed.

  • Granted, whatever came out of a white hole would be a very mangled version of its former

  • self, but nonetheless, information about what it was would not be deleted from the universe.

  • It sounds like a wormhole, but instead of traveling through space, the object would

  • travel through time.

  • General relativity tells us that time moves more slowly near massive objects, so to an

  • object falling into the black hole it would seem like very little time is passing, but

  • to an outside observer, it would take ages to pop out again on the rebound.

  • Just how far into the future it travels depends on the size of the black hole, with big holes

  • taking quadrillions of times the age of the universe to transition.

  • But small black holes that formed just after the chaos of the Big Bang may have already

  • converted.

  • They would be invisible because they’d be smaller than the wavelength of light, but

  • have the mass of about a millionth of a gram.

  • White hole proponents say this could make them an attractive candidate for dark matter.

  • Yeah, the upsides of white holes just keep getting better and better.

  • I told you it would be a wild ride but here is where it comes to an end.

  • I have to remind you that white holes are still purely hypothetical.

  • The math checks out and the reasons to hunt for them are numerous, but at this stage they

  • remain a very unexplored corner of physics.

  • Then again, there was a time when the same could be said about black holes.

  • Were just going to need a few physicists dedicated enough to the idea of white holes

  • to keep searching for them.

  • That or a few brave volunteers to jump into a black hole. huh?

  • Who’s going with me, huh?

  • Anyone?...Anyone?

  • White holes may form faster when the black holes are less massive, but black holes themselves

  • can merge and get bigger.

  • There’s a debate whether the very biggest supermassive black holes can come together

  • and for more on that check out my video here.

  • Alright, so I mean it. Who's jumping in with me huh?!

  • Who's going in the nearest black hole?!

  • Let us know down in the comments below. Be sure to subscribe to Seeker,

  • and I will see you next time.

Longtime viewers of this channel know that we talk about black holes a lot.

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