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2021-11-17: Are Black Holes Actually Fuzzballs?

  • 01:48: Black holes should have an enormous number of so-called microstates - hidden configurations - and this translates to an enormous entropy.
  • 01:58: ... that black holes “have no hairs” to describe the absence of observable microstates in a black hole, which, on the surface, seems to contradict his black ...
  • 06:37: ... guys found a way to count the microstates on the horizon- the number of possible configurations of stringy ...
  • 07:13: ... a compelling reason to think that string theory might explain where the microstates of black holes ...
  • 01:48: Black holes should have an enormous number of so-called microstates - hidden configurations - and this translates to an enormous entropy.

2018-07-25: Reversing Entropy with Maxwell's Demon

  • 02:52: There are only a few configurations that look like this, which means knowing the macrostate almost tells you the exact microstate.
  • 09:26: ... entropy of the universe must increase, and yet knowing the microstate of a system, no matter how thermodynamically mixed, allows you to ...
  • 01:31: ... defined by the number of possible configurations of particles-- or microstates in physics-speak-- that could produce the same observed set of ...
  • 02:29: ... are around 10 to the power of 108 possible microstates that give you this smoothly distributed macrostate, and you'd need close ...
  • 04:26: ... average thermodynamic properties are the same everywhere, are just weird microstates among the many microstates of a very high entropy ...
  • 11:49: ... out there, the ergodic hypothesis is basically the assumption that all microstates are equally probable over long periods of ...
  • 12:13: If different microstates can have different probabilities, then you need to include those probabilities in your equation for entropy.
  • 13:08: Zombie Blood would like us to walk through the math used in calculating the number of possible microstates on the Go board.

2018-07-18: The Misunderstood Nature of Entropy

  • 04:29: We call this the microstate.
  • 05:18: So if you look at the system at some random point in time, it'll be in a completely random microstate chosen from all possible microstates.
  • 05:41: Every possible specific arrangement is considered a microstate, while the overall shape of the distribution would be the macrostate.
  • 06:09: That microstate is a factor of 2 times 10 to the power of 107 less likely than one of the many smoothly mixed microstates.
  • 06:49: And instead of particles being distributed through position space, a microstate is really defined by how energy is distributed through phase space.
  • 08:04: ... look highly ordered but are still consistent with their high-entropy microstate. ...
  • 08:59: ... increase in entropy, simply because at any future time, it's current microstate will most likely be one of the more common types of ...
  • 09:12: ... each Go stone and place it on a particular spot to construct a special microstate or to use a vacuum pump and a glass wall to move all of the air to one ...
  • 05:18: So if you look at the system at some random point in time, it'll be in a completely random microstate chosen from all possible microstates.
  • 04:45: For a given macrostate, all microstates consistent with its thermodynamic properties are equally likely.
  • 04:52: ... some macrostates, there are lots of different microstates or arrangements of particles that lead to roughly the same thermodynamic ...
  • 05:06: ... a system to do its own thing, it'll eventually try out all possible microstates that are possible given the laws of ...
  • 05:18: So if you look at the system at some random point in time, it'll be in a completely random microstate chosen from all possible microstates.
  • 05:29: Well, probably the one that's consistent with the most microstates.
  • 05:59: Some microstates are weird though, and they give different macrostates because they're different average distributions.
  • 06:09: That microstate is a factor of 2 times 10 to the power of 107 less likely than one of the many smoothly mixed microstates.
  • 07:47: ... equation tells us that entropy is the logarithm of the number of microstates consistent with the current macrostate times the Boltzmann ...
  • 08:04: ... the way, there are certain special microstates, special arrangements of particles that look highly ordered but are still ...
  • 08:49: So the macrostate that defines thermodynamic equilibrium is, by definition, the one with the most microstates, which also means the maximum entropy.
  • 09:24: In both cases, you are reducing the number of accessible microstates which, by definition, must reduce entropy.
  • 10:45: ... future, but for now, please be careful to keep your number of accessible microstates low, avoid thermal equilibrium, and keep being that brilliant macrostate ...
  • 04:45: For a given macrostate, all microstates consistent with its thermodynamic properties are equally likely.
  • 07:47: ... equation tells us that entropy is the logarithm of the number of microstates consistent with the current macrostate times the Boltzmann ...
  • 10:45: ... future, but for now, please be careful to keep your number of accessible microstates low, avoid thermal equilibrium, and keep being that brilliant macrostate that ...
  • 08:04: ... the way, there are certain special microstates, special arrangements of particles that look highly ordered but are still ...
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