Monocle
Member
Great minds think alike.
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New Scientist: "String theory may limit space brain threat"
- Thread starter twobear
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Well damn, misread it then.
The construction of this still stinks of handwaving then. A brain popping into existence in space would instantly die, lacking conditions to function. If you go about filling in those conditions, though, you might as well be starting an entirely new universe.
Rygar 8 Bit
Jaguar 64-bit
if spore was right about anything then yes the universe is filled with sentient ding dongs
Thug Waffle
Member
I hope this doesn't mean we'll have to deal with renegade Q beings.
The Smoking Bun
Banned
Space brains should be enemies in the next Halo...
Both of you came up with that at the exact same time. Gafman Boner Brain.
Neuromancer
Member
Doesn't the fact that we exist at all prove that we won the war against the space brains in the future?
The point, if I understand it, is that we take our observation of the universe to be basically typical for an observer. But if the spacebrain is real, they exist in basically infinite quantities in the far-future, high-entropy universe. That means that how we observe the universe now is actually the universe in an incredibly special state i.e. we are incredibly atypical observers. But cosmological theories often depend on our being typical observers. So if the spacebrains are real, theories that assume we are typical observers would be highly problematic.
No, they are waiting for us to reach a technological trigger point. Probably an all-electric SUV that people actually like the look of. As long as it doesn't have gullwing doors we might escape their notice.
So what if we're outnumbered by disembodied brains, we're already vastly outnumbered by space bacteria. By this logic, is the space bacteria secretly laughing at our crude understanding of the universe too? And if so, does that make experiences based on human perception less valid? I'm sure the universe has lots of aspects that humans are unable to perceive. I'm equally sure that the universe has lots of aspects that space bacteria, or space brains, are unable to perceive. Maybe theoretical physicists should spend more time studying how to better perceive the universe, and less time dreaming up theories based on nothing at all.
I think some people are misunderstanding the reason Boltzmann brains are supposed to be a problem. It's not that they're going to encroach on our territory and eat us or some such. IIRC it's more akin to Bostrom's simulation argument.
The simulation argument goes something like this:
-assume that simulations are possible (simulations meaning a whole universe and population of sentient beings that are wholly contained in a computer)
-assume further that simulations within simulations are possible (inside a simulated universe, someone builds a simulated computer and runs a simulated simulation on it)
-once our technology advances enough, there will be lots of different people running these simulations
-oh look, there are now some mind-bogglingly vast number of simulated universes out there
-if there are, it is vastly more likely that we are one of the simulated universes than that we're the lone original universe.
The Boltzmann brain argument is similar:
-I believe myself to be a consciousness experiencing the planet Earth in the year 2013 etc
-One possible explanation for that is that I am a physical brain in a physical body on the planet Earth at that time
-Another possible explanation is that I'm a Boltzmann brain, a randomly arising configuration of particles that happens to correspond exactly to a physical brain on the planet Earth at that time, thus giving rise to an identical experience
-If there are in fact Boltzmann brains, and they do outnumber us (in the future, presumably), then it's more likely that I'm a Boltzmann brain than a physical brain in a physical body
Someone correct me if I'm remembering this wrong.
The simulation argument goes something like this:
-assume that simulations are possible (simulations meaning a whole universe and population of sentient beings that are wholly contained in a computer)
-assume further that simulations within simulations are possible (inside a simulated universe, someone builds a simulated computer and runs a simulated simulation on it)
-once our technology advances enough, there will be lots of different people running these simulations
-oh look, there are now some mind-bogglingly vast number of simulated universes out there
-if there are, it is vastly more likely that we are one of the simulated universes than that we're the lone original universe.
The Boltzmann brain argument is similar:
-I believe myself to be a consciousness experiencing the planet Earth in the year 2013 etc
-One possible explanation for that is that I am a physical brain in a physical body on the planet Earth at that time
-Another possible explanation is that I'm a Boltzmann brain, a randomly arising configuration of particles that happens to correspond exactly to a physical brain on the planet Earth at that time, thus giving rise to an identical experience
-If there are in fact Boltzmann brains, and they do outnumber us (in the future, presumably), then it's more likely that I'm a Boltzmann brain than a physical brain in a physical body
Someone correct me if I'm remembering this wrong.
And all this is a threat exactly because we so hate the idea that our current understanding of the universe we exist in might not only be the only one, but not even the most "valid" one. Oh the horrors!
I love the implications of this.
This was my exact reaction to reading this.
DragonGirl
Member
I'm not exactly worried about an invasion of brains or anything else like it. If all things are possible, then impossibility is one of the possible scenarios. So, regardless of time scales, I'm pretty sure it's possible that space brains are impossible.
I'm wondering why the number of observers is more important than the vantage of those observations.
you're blowing my mind
I dont get what 'typical observer' means.
And I dont understand how space brains just form from nothing. And if the universe continually expands and everything moves away from one another, doesn't that decrease the chances of things coming together?
This makes ZERO and less sense to me.
Monocle
Member
Welcome to philosophy, where everything is possible and nobody knows anything.
so space dicks basically?
Ok, this makes sense, but it's ultimately philosophical and on the same level as being in the Matrix or God willing the universe into existence yesterday.
Going back to my previous point of instant spacebrain death, though, if we're in a child universe that exists just to support our brains, then it not being the parent universe isn't really a big deal.
This theory encompasses anything...including full humans and chairs
Good lord that scares me
The Technomancer
card-carrying scientician
Vacuum energy and all that awesome stuff. Random particles pop into and out of existence at every moment. Theoretically given infinite time any possible configuration of particles will form.
Sure, but you can still rank relative probabilities of spontaneous existence based on complexity.
Sho_Nuff82
Member
$40k a year for this?
Alright, but I'm still not understanding how their existence, or possible existence, matters at all. Does it matter that they're brains? Would spontaneous Ferrari Testarossas be an equal problem? Why does the number of them matter? What does any of this have to do with how we see things?
Okay, well, think of it in terms of being in a very very large field with a single daisy in it. If you pick a random location in the field, the chance of it being within 1cm of the daisy is very small, because the number of locations in the field that aren't within 1cm of the daisy is much larger. A 'typical' location will not be within 1cm of the daisy, and locations within 1cm of the daisy are 'atypical'.
The same is true for our observations of the universe. Cosmologists sometimes reason by assuming that we are typical observers in the universe—this is often called the Copernican Principle. But if the majority of observers in the universe are Boltzmann brains, then we are not typical observers, because we happen to live in a comparatively low entropy period whereas they will overwhelmingly exist in the high entropy, stable period at the end of the universe, where time no longer has a direction.
Because in quantum mechanics, all physically possible events have a non-zero chance of occurring. So for instance, you could find an electron in the nucleus of an atom because it has a non-zero chance of being there. You could also find it on the other size of the universe.
Moreover, in quantum field theory particles can be created from a quantum field. So there's a nonzero chance that a configuration of particles identical to a human brain will be spontaneously created out of background fields in space. Or at least, that's the idea.
Lost Fragment
Obsessed with 4chan
Well if this theory is true, it means that somewhere, a trillion years in the future, you'll be reborn again and live your life exactly as you did here and now.
With infinite time the population of these entities is infinite
The Technomancer
card-carrying scientician
Sure, but I could have sworn I had my mind blown a few years back by the idea that two things could both be infinite but not equal. I think it was specifically in terms of unequal probabilities as well.
The simpler entites would have larger infinite populations
The Technomancer
card-carrying scientician
Right, thats my point. I think we agree?
Yes, there are infinities of different sizes. The cardinality of the real numbers is larger than the cardinality of the integers, for instance.
This isn't the best example given that the probability of an s orbital electron being in the nucleus is considerable.
Trojita
Rapid Response Threadmaker
Fenderputty
Banned
We both must like cartoon rabbits!
Monocle
Member
Yep, space dicks.
How are these spacebrains typical observers? Why do they get that label? Why aren't rocks typical observers? What does it mean to 'observe' in this context? If these brains cant survive, then what does it matter?
And what sort of cosmological principles wouldn't work anymore? What assumptions are being made that would be ruined by the existence of theoretical spacebrains later on?
I dont think I'm going to be able to wrap my head around this.
Space dicks
with the universe, likely is likely enough and likely enough for 1 is likely enough for 1 billion.
The brain bit isn't literal. Just, a spontaneous form of consciousness. It's not unheard of.
don't be bitter.
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