Lubos Motl already discussed this in this blog. if we were Boltzmann brains we wouldn’t expect to see any consistency in physical laws, moments would happen at random. Of course there would be a a very low measure subset of boltmann brains that perceived there to be our physical laws, but its far more likely that the physical laws exist.
There were recent article which showed flaw in this reasoning https://arxiv.org/abs/1702.00850
and I agree with the flaw: BB can’t make coherent opinions about randomness of its environment, so the fact that we think that it is not random doesn’t prove that it is not random.
But if we are BB—we are in fact some consequent lines of BBs, which could be called similar observer moments. Such similarity exclude randomens, but it is a property of a line.
Simplified example: imagine there is infinitely many random numbers. In these numbers exists a line goverened by some rule, like 1,10,100,1000,10 000 etc. Such line will always have next number for it inside the pile of numbers (this is so called Dust theory in nutshell). If each number is decribing observer-moment, in all BBs there will be sequences of observer-moments which corresponding to some rule.
More over, for any crazy BB there will be a line which explains it. As a result we get the world almost similar to normal.
The idea needs longer explanation so I hope on understanding here and I am not trying to prove anything
I understand what you are saying. But I think you cannot reasonably speak of BBs in that way. I think BB is just a skeptical scenario, that is, a situation where everything we believe is false or might be false. And BB has the same problems that all situations like that have. Consider a different skeptical scenario: a brain in a vat.
Suppose you ask the person who is a brain in a vat, “Are you a brain in a vat?” He will say no, and he will be right. Because when he says “brain” he is referring to things in his simulated world, and when he says “vat,” he is referring to things in his simulated world. And he is not a simulated brain in a simulated vat, even though those are the only kind he can talk about.
He is a brain in a vat only from an overarching viewpoint which he does not actually have: if you want to ask him about it, you should say, “Is it possible that you are something like a brain in something like a vat?” And then he will say, “Of course, anything is possible with such vague qualifications. But I am not the kind of brain I know about, in the kind of vat I know about.” And he will be right.
The same thing is true about BBs. If you look at BBs in the world you are talking about, moments of them say things like “I will wake up tomorrow.” And even though according to our viewpoint they are just moments that will cease to be, they are talking about the continuous series that you called a normal life. So they are right that they will wake up, just like the brain in the vat is right when it says “I am not a brain in a vat.” So they say “We are not BBs”, and they are right. They are BBs only from an overarching point of view that they do not have.
So what that means for us: we are definitely not BBs. But there could be some overarching metaphysical point of view, which we do not actually have, where we would be something like BBs (like the brain in the vat says it might be something like a brain in a vat.)
Yea Carroll has rather the obsession with Boltzmanns brains. Both sides have vaild arguments if we were living in a boltzmann brain dominated universe random observations would be more likely but no amount of measuring would prove that you weren’t a boltzmann brain.
Of course Carroll repeatedly tries to use this to argue agaist a universe dominated by boltzmann brains, but it does no such thing all it means is that he WANTS the universe not to be dominated by boltzmann brains because if it is then his life work was a waste of time :P
I actually read that paper and he actually says that we should reject BB dominated univereses on the basis that they don’t allow physicists to make predicitions, man that guy is an idiot
Lubos Motl already discussed this in this blog. if we were Boltzmann brains we wouldn’t expect to see any consistency in physical laws, moments would happen at random. Of course there would be a a very low measure subset of boltmann brains that perceived there to be our physical laws, but its far more likely that the physical laws exist.
There were recent article which showed flaw in this reasoning https://arxiv.org/abs/1702.00850 and I agree with the flaw: BB can’t make coherent opinions about randomness of its environment, so the fact that we think that it is not random doesn’t prove that it is not random.
But if we are BB—we are in fact some consequent lines of BBs, which could be called similar observer moments. Such similarity exclude randomens, but it is a property of a line.
Simplified example: imagine there is infinitely many random numbers. In these numbers exists a line goverened by some rule, like 1,10,100,1000,10 000 etc. Such line will always have next number for it inside the pile of numbers (this is so called Dust theory in nutshell). If each number is decribing observer-moment, in all BBs there will be sequences of observer-moments which corresponding to some rule.
More over, for any crazy BB there will be a line which explains it. As a result we get the world almost similar to normal.
The idea needs longer explanation so I hope on understanding here and I am not trying to prove anything
I understand what you are saying. But I think you cannot reasonably speak of BBs in that way. I think BB is just a skeptical scenario, that is, a situation where everything we believe is false or might be false. And BB has the same problems that all situations like that have. Consider a different skeptical scenario: a brain in a vat.
Suppose you ask the person who is a brain in a vat, “Are you a brain in a vat?” He will say no, and he will be right. Because when he says “brain” he is referring to things in his simulated world, and when he says “vat,” he is referring to things in his simulated world. And he is not a simulated brain in a simulated vat, even though those are the only kind he can talk about.
He is a brain in a vat only from an overarching viewpoint which he does not actually have: if you want to ask him about it, you should say, “Is it possible that you are something like a brain in something like a vat?” And then he will say, “Of course, anything is possible with such vague qualifications. But I am not the kind of brain I know about, in the kind of vat I know about.” And he will be right.
The same thing is true about BBs. If you look at BBs in the world you are talking about, moments of them say things like “I will wake up tomorrow.” And even though according to our viewpoint they are just moments that will cease to be, they are talking about the continuous series that you called a normal life. So they are right that they will wake up, just like the brain in the vat is right when it says “I am not a brain in a vat.” So they say “We are not BBs”, and they are right. They are BBs only from an overarching point of view that they do not have.
So what that means for us: we are definitely not BBs. But there could be some overarching metaphysical point of view, which we do not actually have, where we would be something like BBs (like the brain in the vat says it might be something like a brain in a vat.)
Interesting thoughts, thanks. Surely we are not BBs in our model of the world, but on some meta level we could be them.
Yea Carroll has rather the obsession with Boltzmanns brains. Both sides have vaild arguments if we were living in a boltzmann brain dominated universe random observations would be more likely but no amount of measuring would prove that you weren’t a boltzmann brain.
Of course Carroll repeatedly tries to use this to argue agaist a universe dominated by boltzmann brains, but it does no such thing all it means is that he WANTS the universe not to be dominated by boltzmann brains because if it is then his life work was a waste of time :P
I actually read that paper and he actually says that we should reject BB dominated univereses on the basis that they don’t allow physicists to make predicitions, man that guy is an idiot