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2019-12-09: The Doomsday Argument

  • 15:07: That means it's also possible to produce a closed, positively curved bubble universe within an infinite inflating multiverse.

2019-11-11: Does Life Need a Multiverse to Exist?

  • 12:04: ... Linde’s eternal inflation is perhaps the most popular - bubble universes forming in a larger exponentially expanding spacetime, and in each ...

2019-09-30: How Many Universes Are There?

  • 00:06: But just how many bubble universes does the eternally inflating multiverse contain?
  • 00:34: But in the eternal inflation picture, ours is just one among uncountable bubble universes.
  • 02:18: Some questions spring to mind: - I mean, besides “What?!?” For example, how many bubble universes can be made this way?
  • 02:52: ... challenge question I asked you to calculate the RELATIVE number of new bubble universes that formed in one second compared to the previous ...
  • 03:05: We assumed that there’s a fixed but unknown probability that a bubble universe will form in any given volume of inflating space.
  • 03:21: So the rate at which that volume is increasing is the same as the rate at which bubble universes multiply.
  • 04:44: And our number of new bubble universes should multiply by the same insane factor each second.
  • 05:33: Here’s another one: do all of these bubble universes the same laws of physics, or could they be wildly different from each other?
  • 06:43: Here’s a possible explanation: what different bubble universes can end up with different vacuum energies?
  • 06:51: ... vacuum energies like ours might be extremely rare, but there are so many bubble universes that at least some will have a low enough cosmological constant for life ...
  • 11:29: He proposes that there may be something off in the logic of weighing up probabilities over bubble universes.
  • 14:43: Alexander has been traveling the bubble universes for many years, supporting local youtube space shows where he finds them.

2019-08-26: How To Become an Astrophysicist + Challenge Question!

  • 08:59: ... process goes on forever but inflation also has a beginning. So how many bubble universes exist ...
  • 10:46: ... new universe forming in any given volume of space So every second many bubble universes are forming across the great sir Eternally, inflating space-time and ...

2019-08-19: What Happened Before the Big Bang?

  • 09:06: ... a fractal structure of infinitely expanding space in dispersed with bubble universes of all different ...

2019-08-06: What Caused the Big Bang?

  • 12:49: eternally - Only stopping in patches where a bubble universe forms. And once started, inflation should produce infinite such universes.

2019-07-18: Did Time Start at the Big Bang?

  • 09:52: ... We'll get to the nitty-gritty of that with its inflow tongs and bubble universes real soon There are also various cyclic universe options the first ...

2019-03-06: The Impossibility of Perpetual Motion Machines

  • 11:13: ... outlandish goes to Epsilon Centauri, whose machine requires an entire bubble universe with closed, pac-man borders, trapping the ever-accelerating ...

2017-06-21: Anti-Matter and Quantum Relativity

  • 13:12: ... username asks whether colliding universes in the bubble universe scenario means that we redefine "universe" to be the bounded ...
  • 13:34: But this bubble universe idea does suggest a greater universe beyond our bubble.
  • 13:50: Galdo145 asks whether bubble universes with different vacuum energies would convert to the lower energy state after colliding?

2017-06-07: Supervoids vs Colliding Universes!

  • 09:22: This can happen spontaneously anywhere in the greater inflating space time, resulting in bubble universes.
  • 09:37: But regardless, in an infinitely inflating space time, collisions between bubble universes are eventually expected.
  • 09:45: So what happens when two bubble universes collide?

2016-10-12: Black Holes from the Dawn of Time

  • 03:21: For example, the collapse of cosmic string moves and the collision of bubble universes?

2015-09-30: What Happens At The Edge Of The Universe?

  • 07:22: Now, bubble universes may be finite in size regardless of internal geometry.
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