Your memories are almost certainly false

[RexAllen]

Rule Britannia already addressed those links perfectly adequately. I saw no need to repeat his post.

Right. That's because you're apparently not very smart. He's 23. Youthful exuberance. I'm not sure what your excuse is.

The Poincaré Recurrence Theorem applies only to volume-preserving systems. The universe certainly does not fall under this category so it does not apply in this case.

This is where you should have read the references in the first link, where they explicitly discuss how an expanding universe resurrects the Boltzmann brain problem due to de Sitter radiation coming from the cosmological horizon.

I told you. Read the effing links.

Your ignorance I can take. Your arrogance is starting to get old.

[fordo]

bookmarking from time to time i get bored and like to read obtuse nonsence, it slows down my suicidal impulses,continue

[Azathoth]

Would you be another incarnation of the guy who posted all the text walls of Tipler nonsense perhaps?

[RuleBritannia]

RexAllen I'll look out for you when they announce next years Nobel Prize winners, I probably won't see you though 'cause you're clearly an idiot.

[Azathoth]

oh and,

[RexAllen]

RexAllen I'll look out for you when they announce next years Nobel Prize winners, I probably won't see you though 'cause you're clearly an idiot.

If your previous posts hadn't been so lame as to indicate mental deficiency, that might have stung.

Again, none of the ideas presented are mine. All the information is in the links provided.

Some advice:

"Fat, drunk and stupid is no way to go through life, son."

[RexAllen]

Would you be another incarnation of the guy who posted all the text walls of Tipler nonsense perhaps?

Nope. That was a different crackpot.

[RexAllen]

BTW, Sean Carroll's From Eternity to Here is very good.

Particularly this chapter:

http://blogs.discovermagazine.com/cosmi ... apter-ten/

After the amusing diversions of the last chapter, here we resume again the main thread of argument. In Chapter Eight we talked a bit about the “reversibility objection” of Lohschmidt to Boltzmann’s attempts to derive the Second Law from kinetic theory in the 1870’s; now we pick up the historical thread in the 1890’s, when a similar controversy broke out over Zermelo’s “recurrence objection.” The underlying ideas are similar, but people have become a bit more sophisticated over the ensuing 20 years, and the arguments have become a bit more pointed. More importantly, they are still haunting us today.

One of the fun things about this chapter is the extent to which it is driven by direct quotations from great thinkers — Boltzmann, of course, but also Poincare, Nietzsche, Lucretius, Eddington, Feynman. That’s because the arguments they were making seem perfectly relevant to our present concerns, which isn’t always the case. Boltzmann tried very hard to defend his derivation of the Second Law, but by now it had sunk in that some additional ingredient was going to be needed — here we’re calling it the Past Hypothesis, but certainly you need something. He was driven to float the idea that the universe we see around us (which, to him, would have been our galaxy) was not representative of the wider whole, but was simply a local fluctuation away from equilibrium. It’s very educational to learn that ideas like “the multiverse” and “the anthropic principle” aren’t recent inventions of a new generation of postmodern physicists, but in fact have been part of respectable scientific discourse for over a century.

It’s in this chapter that we get to bring up the haunting idea of Boltzmann Brains — observers that fluctuate randomly out of thermal equilibrium, rather than arising naturally in the course of a gradual increase of entropy over billions of years. I tried my best to explain how such monstrosities would be the correct prediction of a model of an eternal universe with thermal fluctuations, but certainly are not observers like ourselves, which lets us conclude that that’s not the kind of world we live in. Hopefully the arguments made sense. One question people often ask is “how do we know we’re not Boltzmann Brains?” The realistic answer is that we can never prove that we’re not; but there is no reliable chain of argument that could ever convince us that we are, so the only sensible way to act is as if we are not. That’s the kind of radical foundational uncertainty that has been with us since Descartes, but most of us manage to get through the day without being overwhelmed by existential anxiety.

[RuleBritannia]

RexAllen I'll look out for you when they announce next years Nobel Prize winners, I probably won't see you though 'cause you're clearly an idiot.

If your previous posts hadn't been so lame as to indicate mental deficiency, that might have stung.

Again, none of the ideas presented are mine. All the information is in the links provided.

Some advice:

"Fat, drunk and stupid is no way to go through life, son."

Good one.

[FBM]

RexAllen I'll look out for you when they announce next years Nobel Prize winners, I probably won't see you though 'cause you're clearly an idiot.

MOD NOTE:

RuleBritannia, this is clearly unacceptable.

Edit: I read further back and found where rex had insulted XC first, calling him "arrogant" and "ignorant" and the like. Neither of these responses are appropriate in this kind of discussion.
END MOD NOTE:

[Twiglet]

RexAllen - The consequences of the second law of thermodynamics Feynmann was discussing in the ratchet and pawl experiment were about whether it is possible to decrease entropy by extracting work from heat, and he proved that it isn't.

That doesn't have anything to do with whether it's possible for an ordered system (like a living organism) to maintain it's order at the expense of creating more disorder elsewhere. That's not a violation of the second law of thermodynamics, in fact, it is entirely consistent with it.

[Xamonas Chegwé]

Allow me to address a rather large elephant in this room.

Rex. You have started two similar threads now and in both of these you attempt to use established science, mainly physics, to establish the theory that the universe that we perceive is almost certainly illusory. In short, you are trying to provide a scientific proof for solipsism. Would that be fair?

The problem is that the physics that you are hoping to use to establish your theory only apply in the universe is as we perceive it. In other words, prove your theory and the proof is immediately invalid!

Solipsism belongs in the realm of speculation. By its very nature, it cannot be disproved scientifically. It is nothing but an interesting mental diversion - until we wake up one morning in a tank in the Matrix.




Allow me now to address the concept of the Bolzmann Brain a little more fully.

The idea (as I understand your usage of the concept) is that a completely random universe is capable of throwing up any combination of particles and that, given infinite time, some of these combinations will be conscious entities possessing what they believe to be memories and sensory input from an outside universe - however, the probability is almost infinitely more likely that this data will be false.

This is interesting as a mental exercise but I can see flaws on a lot of levels.

Firstly, it would require a universe capable of continuously producing arrangements of particles of the required complexity such that consciousness could occur within that arrangement. Our universe (as understood by modern physics) is not capable of producing all combinations of particles. For example, it is not capable of creating any arrangement in which there is less overall entropy than any previous arrangement. It is not certain, therefore, that it is capable of producing any such conscious entity randomly - the principles of natural selection of self-replicating molecules leading to the required complexity are another matter entirely, as is the implanted memories coming from genuine sensory input.

Secondly, even if such entities could arise randomly in this universe, the energy in the universe is finite and its net entropy is constantly increasing. This means that there will come a point where no localised system of the required complexity can arise - hence, there is not an infinite duration within which the universe can 'try out' many different random brains.

Thirdly, even should there be a huge amount of randomly created brains out there, with randomly created memories, the odds are (as you quite rightly claim) almost infinitely against any one of them having true knowledge of the nature of their universe. However, the odds are also almost infinitely against them having any coherent and consistent knowledge of their universe at all, however true or false it might be! The only safe bet as to how such an internally consistent and coherent set of knowledge could find itself lodged in a brain is that that brain actually experienced those things by some method.

My first and second points make it almost infinitely unlikely that a universe such as ours could throw up a Boltzmann Brain. The theory would therefore require a different kind of universe altogether, hence returning to my earlier point - it is pointless using human physics to argue the case.

My third shows that, if we are living inside the Matrix, we should be seeing a lot more glitches!

[Azathoth]

Would you be another incarnation of the guy who posted all the text walls of Tipler nonsense perhaps?

Nope. That was a different crackpot.

OK, so you you are just playing devil's advocate for this silliness then. Carry on

[RexAllen]

RexAllen - The consequences of the second law of thermodynamics Feynmann was discussing in the ratchet and pawl experiment were about whether it is possible to decrease entropy by extracting work from heat, and he proved that it isn't.

That doesn't have anything to do with whether it's possible for an ordered system (like a living organism) to maintain it's order at the expense of creating more disorder elsewhere. That's not a violation of the second law of thermodynamics, in fact, it is entirely consistent with it.

I'm not sure what you're referring to. I never said that living organisms are violations of the second law.

To summarize the thread thus far:

The claim was made, by Xamonas that the situation described in the OP violates the second law of dynamics.

I (correctly) pointed out that it doesn't, because it is effectively the same situation as the brownian ratchet, just scaled up. Statistical fluctuations from thermal equilibrium will occur. Larger fluctuations are just much more rare. Extremely large fluctuations are not impossible, they're just extremely rare.

The fact that orderly fluctuations away from thermal equilibrium occur is *not* a violation of the second law because you can't use this fact to do any useful work.

Also, RuleBritannia said some irrelevant stuff and got dinged by the moderator. Kids these days. What are you gonna do?

[Twiglet]

You can extract useful work by increasing entropy. That's what living systems do. It has nothing to do with fluctuations of the type that occur in Brownian motion.