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2022-04-20: Does the Universe Create Itself?

  • 17:08: ... physics. In a way that’s right. If the universe is a black or a white hole then it formed by a different process than the black holes that we’ve ...

2022-03-30: Could The Universe Be Inside A Black Hole?

  • 06:05: It’s a white hole, and it’s a valid a solution to the Einstein equations.
  • 06:13: ... past, space-like singularity of the white hole is surrounded by an event horizon that is the opposite to a black hole ...
  • 06:35: But there’s still an “outside” in which the white hole appears as a bright, localized point in space.
  • 06:48: On the other hand, anyone inside the white hole wouldn't know that.
  • 06:59: At first glance, despite the similarities the interior of the white hole looks nothing like our universe.
  • 07:06: Now the white hole was “discovered” by messing around with the coordinates of the OG black hole solution by Karl Schwarzschild.
  • 07:22: The interior of this type of white hole looks nothing like our universe.
  • 08:05: But there is actually a way to fit an FLRW metric inside a black or white hole so that those inside it couldn’t tell the difference.
  • 09:43: If it works for the black hole then it should work for the white hole.
  • 09:47: Just flip the timel axis and you have a white hole containing a bubble of expanding space that looks much like our universe.
  • 09:55: If such a white hole was big enough, it could look exactly like our universe.
  • 10:14: There’s also the idea that universes are born as white holes produced after the collapse of a black hole.
  • 10:27: ... rather bounce back outward to create a new spacetimes from the resulting white hole - which itself creates new black holes, ...
  • 10:48: ... from the cosmic microwave background - then the line between the white hole and black hole becomes ...
  • 11:08: ... you lump all of this together - a very specific construction for white holes to make them look like our universe from within, and Hawking’s argument ...
  • 11:27: Or a white hole?

2022-03-23: Where Is The Center of The Universe?

  • 10:53: We might ask whether the Big Bang is a reverse black hole - also called a white hole.

2021-09-21: How Electron Spin Makes Matter Possible

  • 16:27: ... were just discovered and there was speculation that they might be white holes. So I came along only a little after, I imagine those were giddy exciting ...

2020-06-22: Building Black Holes in a Lab

  • 05:01: ... is in the opposite direction to the waves this is actually an analog white hole. Other experiments use a carefully-shaped hole in a tank to create a ...

2020-05-18: Mapping the Multiverse

  • 09:45: It leads to what looks like a white hole.
  • 09:49: Now we saw that in the Schwarzschild solution, a white hole exists in the past of a purely hypothetical eternal non-rotating black hole.
  • 10:00: The Kerr black hole also has a white hole in the past, but it has one in the future too.
  • 10:18: You caught a glimpse of the entire history of that universe the moment you crossed into the white hole.
  • 10:25: That white hole will eject you as forcibly as the black hole pulled you down.
  • 10:49: If you try to head back to the white hole, you won’t find it - you’ll only find a new black hole that lies in its future.

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 04:50: ... universe. The black hole also has a mirror reflection that we call the white hole. ...

2020-03-31: What’s On The Other Side Of A Black Hole?

  • 06:15: ... looks just like the black hole - but with time reversed. This is the white hole, and we’ve this before - but perhaps we’ll get a little more insight into ...
  • 09:39: ... where opinion is divided. Some think that the parallel universe AND the white hole are just coordinate reflections of the regular universe and black hole - ...
  • 09:55: ... depends on how that reflection works. Perhaps you emerge from the past “white hole” traveling forward in time, or from the future black hole but traveling ...
  • 10:35: ... parallel universe and white hole are needed in the map of the eternal Schwarzschild black hole in order ...

2019-01-24: The Crisis in Cosmology

  • 17:01: ...should transform it into a white hole.

2017-09-13: Neutron Stars Collide in New LIGO Signal?

  • 14:47: Regarding our episode on white holes, a few of you wanted some clarification of a point I made.
  • 14:53: I said that the Big Bang is mathematically similar to a white hole, except that it doesn't possess a singularity.
  • 15:13: Now, we can imagine both the white hole and the earliest instant of the Big Bang as possessing infinite or at least extremely high density.
  • 15:21: But for the Big Bang, that density is everywhere, not concentrated at a single point, as in the case of the white hole.

2017-08-30: White Holes

  • 00:14: In fact, it's the black hole's mirror twin-- the white hole.
  • 01:18: One such entity is the white hole.
  • 01:21: A white hole is the opposite of a black hole in a very literal mathematical sense.
  • 01:41: That makes a white hole a region of outward flowing space time.
  • 01:51: Nothing outside a white hole can ever enter, and everything inside must be ejected.
  • 01:56: Not even light can leave a black hole, hence the whole black thing, but light can only leave a white hole.
  • 02:12: ... before everyone gets too excited, white holes are probably a figment of mathematical imagination, but they're a ...
  • 02:26: White holes first emerged in the very earliest mathematical description of black holes.
  • 07:51: So far, this region fits perfectly the description of a white hole.
  • 07:56: The eternal black hole of the past technically is a white hole.
  • 08:06: One, light rays exiting that past white hole can never reach us.
  • 08:34: Even though this type of white hole isn't observable, some physicists have taken the description very seriously.
  • 08:41: The math describing the white hole is a perfectly good use of the Schwarzschild metric.
  • 09:01: So can new white holes actually form?
  • 09:12: ... although it's possible to build a white hole in general relativity, there are other laws of physics that the universe ...
  • 09:46: ... rare entropy dip could lead to an effective reversal of time and a white hole could ...
  • 10:09: We actually did talk about a case where a random drop in entropy lead to something very much like a white hole in this episode.
  • 10:18: ... it happens, the Big Bang looks-- mathematically, at least-- much like a white hole. ...
  • 10:43: The difference between the Big Bang and a white hole is that the former possesses no singularity.
  • 10:57: It's been proposed that, when a black hole forms, a white hole forms on the opposite side.
  • 11:04: Energy entering the black hole exits the white hole.
  • 11:08: ... Lee Smolin takes it a step further to suggest that the resulting white hole is the Big Bang of a new baby universe and that, in fact, our universe ...
  • 11:32: The past white hole was revealed when we traced the eternal black hole backwards in time.

2017-01-19: The Phantom Singularity

  • 12:36: ... our Patreon Google Hangout where he pretty much obliterated the entire white hole hypothesis by correctly pointing out that if they existed in any great ...

2016-12-08: What Happens at the Event Horizon?

  • 11:04: And down here we have what we call a white hole.
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