8 ms·
Fascinating: "10^(10^50) years: Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease." [1] [1] https://en.wikipedia.
by netgusto 8y ago
Fascinating: "10^(10^50) years: Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease." [1]
[1] https://en.wikipedia.org/wiki/Boltzmann_brain https://en.wikipedia.org/wiki/Boltzmann_brain
> [...] a Boltzmann brain is a self-aware entity that arises due to extremely rare random fluctuations out of a state of thermodynamic equilibrium. [...]
- oorza 8y agoIncoming Galactus
- tzahola 8y agoNow calculate the probability of the current Universe arising spontaneously from vacuum.
- eanzenberg 8y ago1
- cpburns2009 8y agoThis feels anecdotal rather than an actual calculation.
- TrainedMonkey 8y agoAssuming that time moves forward, probability of all events that have already happened is 1. Probability of all events that could have happened, but did not 0. There is an interesting parallel that could be made to quantum states collapsing. Given that the question asks about 'current' universe arising spontaneously from vacuum the probability is 1 because that has already happened. The more interesting question, what is the probability of a new universe similar to our own arising. To the best of our knowledge (which for this type of extrapolation is admittedly flimsy) this is also 1, this just takes a very long time. The expected time it would take (10^10^10^56) is specified on the last row on the "Future of the Earth, the Solar System and the Universe" table.
- taneq 8y ago> Given that the question asks about 'current' universe arising spontaneously from vacuum the probability is 1 because that has already happened. Well, we don't know that. Whatever 'came before' (if that even makes sense) probably wasn't a vacuum with the same rules as we see now.
- pc86 8y ago> Probability of all events that could have happened, but did not 0. Only if you meant "could have happened, but did not, and now for some reason can no longer happen." "All events that could have happened, but did not" would reasonably encompass every event with 1 > P > 0, wouldn't it?
- TrainedMonkey 8y agoWhat I specifically meant is that to best of our knowledge past is deterministic, but future is not.
- Florin_Andrei 8y agoIt's the only case where anecdotal evidence is acceptable. Actually, no. That would be the existence of my own consciousness. Just mine. Not yours. That's it.
- PhasmaFelis 8y agoI am hardly a mathematician, so I'm probably missing something, but I think it makes sense? I believe it's well-established that elementary particles can spontaneously generate through quantum fluctuation. Assuming that this process is uniformly distributed, the probability per unit time of any given structure self-generating is nonzero (if fantastically small). Over a long enough timescale, the probability of any possible event occurring approaches one. If time is infinite, the probability is one. What am I missing?
- cpburns2009 8y agoI meant it more tongue-in-cheek than as a real critique. That being said, such a strong statement should have some backing other than anecdotal evidence I agree with. I'm assuming @eanzenberg said the answer is "1" because our universe clearly exists (from my perspective at least). I'd expect the formula to be similar in nature to the Drake equation [1]. However, I'm neither a mathematician nor a physicist. [1]: https://en.wikipedia.org/wiki/Drake_equation https://en.wikipedia.org/wiki/Drake_equation
- netgusto 8y agoGenius.
- ende 8y agoPlease show your work.
- deleted 8y ago[deleted]
- eximius 8y ago
- OscarCunningham 8y agoThey mean probability per second.
- pjc50 8y agoTime is believed to be inside the universe, not outside it; assuming the conventional understanding of spacetime is correct.
- f2f 8y agoit's there at the bottom: 10^10^10^56 "Around this vast timeframe, quantum tunnelling in any isolated patch of the vacuum could generate, via inflation, new Big Bangs giving birth to new universes [...] this is also the time required for a quantum-tunnelled and quantum fluctuation-generated Big Bang to produce a new universe identical to our own, assuming that every new universe contained at least the same number of subatomic particles and obeyed laws of physics within the range predicted by string theory."
- Florin_Andrei 8y agoFun fact: most Boltzmann brains pass out in a matter of seconds, then die, and there's nothing they can do about that.
- AgentME 8y agoMaybe some Boltzmann brains start out with rich fulfilling memories. And then a later (or earlier) Boltzmann brain happens to exist with a continuation of those memories. (Now I realize I'm just reciting a plot point from the excellent book Permutation City...)
- baddox 8y agoAnd likewise, maybe others start out in a state of unimaginable agony with a long memory of the same.
- vinceguidry 8y agoDoes self-awareness presume the existence of emotion? I feel like Boltzman wouldn't have bothered to assert self-awareness if he'd had a real knowledge of the various gradations of consciousness and just how rare they are, even on Earth.
- majos 8y agoAs a dude-do-you-ever-think sidenote, this sort of thing keeps me from getting excited about any type of virtual reality that does anything with our brains. How do I know it won't simulate 10 years of torture, then at the end replace that memory with 10 minutes of an edenic golden field, so when I actually unplug all I have is a nice remembered experience that I'd like (incorrectly) to try again?
- Florin_Andrei 8y agoWell, growing up you have no guarantee your life is going to be 100% sunshine-and-bunnies, and indeed it rarely is. And yet you live.
- andbberger 8y agoThat is __severely__ underestimating the true probability - it considers only random thermal fluctuations. But the universe is really powered by processes that dissipate energy across a gradient to fuel a structured, very low entropy state. The math is the same as calculating the probability that the glass you just broke will spontaneously jump back onto the table and reassemble itself. Which is a standard introductory example in thermodynamics... but you add self-awareness and suddenly this rather mundane thing is spooky and amazing. You should be far more interested in what's happening when you boil a pot of water and convection rolls spontaneously form.
- drewblaisdell 8y ago> You should be far more interested in what's happening when you boil a pot of water and convection rolls spontaneously form. Serious question: why?
- andbberger 8y agohttps://news.ycombinator.com/item?id=17390042 https://news.ycombinator.com/item?id=17390042
- Symmetry 8y agothe universe is really powered by processes that dissipate energy across a gradient to fuel a structured, very low entropy state. By 10^(10^50) years that'll be long over.
- DoctorOetker 8y agowhich is exactly his point...
- Symmetry 8y agoRe-reading the post: no I don't think I can reasonably interpret it so that that was his point.
- 8y ago
- mihaifm 8y agoJust spent some good hours reading about Boltzmann brain related stuff...it's indeed a fascinating topic. The most interesting part is the related Boltzmann brain paradox: we are far more likely to be isolated brains randomly popping out of chaos and imagining a universe, than actually living in a real universe.