I am new to this forum even though I have read a lot on the subject of boltzmann's brains and have come to a terrifying conclusion, the classic argument which for example Sean Carroll used, "The cognitive instability" (https://arxiv.org/abs/1702.00850), is not enough to dispel the doubt, his argument states that if thanks to scientific observations I come to the conclusion that at 99% I should be a Boltzmann brain, then follows that my perceptions are more likely to be random and therefore inconsistent, one falls into a contradiction where if it is true that I am a Boltzmann brain then it does not sense to think so because all the observations that led me to think of it are problably wrong because they are random.

This makes sense for heaven's sake, but there are several problems. The first is that one could argue that a Boltzmann brain could not even survive, it would die immediately from lack of oxygen, blood and nutrients. The second is that it would not be able to form in the sense that, being the Boltzmann brains slowly form (same link above of Sean Carroll), the "meat" of the brain would freeze or should decaying for lack of vital support.

Now, a digression, I did not understand how exactly boltzmann's brains are formed, on Wikipedia, they cite 2: by quantum fluctuation and via nucleation, Sean Carroll cites 3: Vacuum fluctuations, Measurement-induced fluctuations, Boltzmann fluctuations. Now there is a problem, I don't understand too much about physics, if please someone can explain to me at least those from Wikipedia, from what I "understand" is that in quantum fluctuations, the object appears already fully formed, while for those on nucleation, are slowly formed with the accidental union of atoms, although I'm not sure because Wikipedia mentions strange concepts such as de Sitter's cosmological horizon. A question that follows is: particles and atoms in a vacuum can really unite to form macroscopic objects such as a brain, a stone, a computer, etc.. without energy (like in endoergonic reactions), so it seems strange to me that atoms in a vacuum can be connected at random. It would seem even more strange to me if atoms such as carbon and nitrogen for example, but any pair of atoms with different atomic numbers, can join together to form a heavier element, for example: hydrogen + hydrogen = helium, as occurs in nuclear fusion. It seems strange to me that it can happen in a vacuum without great energy.

When I realized that on its own it is impossible (I think) for a Boltzmann brain to survive, an idea came to my mind. Being that eternity or nearly so, (if the proton does not decay, it is estimated that before the "heat death" will pass 1010120, source: https: //en.m.wikipedia.org/wiki/Future_of_an_expanding_universe) it is very long as time, also form other objects, such as computers, and being that in a possibly infinite period, the most likely events will occur more frequently, computers will be formed , most will have a meaningless code, but there will be a small part of them that will have a meaningful code and that another fraction of this, will want to form human brains (because an entire human needs more nourishment) and simulating an external world in their mind. That's a tiny part of computer, but compared to the only one I'm supposed to be living on Earth, there are a lot more that are going to be living in the distant future, how likely are I to be in the only life on earth?

Now, there are several obstacles that these computers have to face in order to do such a thing, I will divide them into 5 themes:


2)particles to create a human mind

3)Computing power needed

4)Computer knowledge

5)Errors in the simulation

1)a computer could take energy from Hawking radiation from a black hole, a neutron star or a star of iron (iron beads that are formed in the distant future, see link: https://en.m.wikipedia.org/ wiki / Future_of_an_expanding_universesince blacks holes will rule for more time, so I assume that they take energy from there, maybe a black hole rather small that releases more energy.

2)a computer could travel for a long time and a lot of space, collecting atoms and then combine them and create a brain, would not be as impossible because there is no friction being empty space, so it would take a small initial boost and a small to dodge blacks holes or objects dangerous

3)since the fluctuations that form smaller objects are more probable, a traditional computer is to be excluded given the size of our universe, we would need a quantum computer that would require 615 qubits to simulate our universe(https://medium.com/data-driven-fiction/how-many-bits-to-simulate-the-universe-f60489f5ddce), and being the temperature already close to absolute zero, you don't even need a cooling system, so the size is very modest

4)here (fortunately) you have the greatest problems, being a computer created by chance, the more coherent information it has, the less likely it is, so it could form with "only" the knowledge necessary to form a human brain and keep it alive for a moment (in this so if really the most probable scenario is this and I am clearly not dead then we can say a priori that for some reason these computers will not form, without testing it with experiments), even if an AI could also be created that understands and is able to deduce through attempts and study of the remaining matter, how to create a human brain (a small percentage will do so, albeit in quantities larger than the one human life) and how to keep it alive and make them live a life in a simulated world. Now, I don't know which of the two will happen more often

5)I think errors occur but they will still be hidden from the computer I have thought of different solutions, but none of them seem convincing to me, and you have to understand one thing, you have to understand what is the most likely situation that will happen in which a brain that lives, at least for a short time. I greatly fear, I'm terrified because I think that the situation most likely expected that I survive long in a simulation because if a computer is able to form a brain and keep me alive, then it means that it is already very intelligent, and therefore will deceive me completely, because if the computer was more "stupid", it would not even survive and form me and make me in Life for a moment.

however the solutions I found are: 1) due to quantum tunneling, all the baryon matter will become iron and furthermore there will not be enough energetic photons to form matter through the pair production, in this way at least for one way of formation by mixing particles a chance, it won't be possible, I don't know about quantum fluctuations. 2) particles do not join in vacuum (reason explained better above). 3) it is more likely that a computer will be formed that only knows how to do what is necessary to create a human brain and make it survive for a short time than a computer that understands the universe and also manages to deduce more or less what happened in the distant past . 4) if the goal of the computer is to simulate, I don't think it wants me to find myself in a horrible life that will surely lower my life span and therefore simulate for less time. It could at least, I don't know, create a brain less predisposed to anxiety and a society that feeds it less. 5) the protons decane and therefore the universe goes into thermal death first, so even if boltzmann computers are created, they will not have the energy to maintain a human brain. 6) maybe there's something I'm forgetting that prevents all this.

I know I wrote a long text but I really afraid, please if you can answer me at least something, thanks


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Everything you know about physics and formation of clusters of matter is just part of the false-history that the Boltzmann brain experiences.  For purposes of the thought experiment, assume the least convenient universe - pure randomness.  It just so happened that your entire set of memories came into being, experienced this millisecond, and then will dissolve.  

Behind this is the idea that there is no perception of the actual present.  Each unit of experience (minimum time-slice) is entirely memories, plus inputs at least a few hundred milliseconds old.  The next time-slice is connected by our perceptions, but in a BB, there would be no next time-slice, just the one.

how would it survive even for a second or just form without dying first?

It doesn't survive.  It exists just long enough for you to have one atomic moment of experience, then dissolves.  Continuity, causality, and movement through time is an illusion caused by happenstance of the memories that are part of this ephemeral random configuration.
okay, but unfortunately we can't help but to talk with our human categories, so do you think it should appear for a moment and then dissolve?
Well the Boltzman Brain idea is deep into the Solopsistic corner of simulation-like hypotheses, so "we" is just as unproven as anything else in my instantaneous experience of memory.   My point is that the concept doesn't require continuity or persistence.  Experience feels continuous, but as far as anyone can tell, that mechanism is via memory and brain-state.  And brain-state does not imply that the only way to get that state is via a sequence of changes - perhaps it comes into being instantaneously by luck (or by some agency that's irrelevant to the thought experiment). 

I get the sense that you should enjoy learning more physics, and shouldn't worry about Boltzmann brains again until you at least have a physics-based intuition for whether we expect Boltmann brains or the decay of iron stars to come first.

Still, some links that might interest you:





Thanks for the answer! I have read all the links even if I did not understand much of the first one, of the second I understood that quantum fluctuations do not occur, even if, as I say in the post, I did not understand if the particles in the vacuum can be combined to create macroscopic objects, and what does "via nucleation" mean. Thanks anyway

Your issue is not Boltzmann brains at all. It's basic rationality: noticing your own confusion and therefore giving very low weight to your own confused arguments (and fears). There are many many scary things one can imagine, and Boltzmann brains are not even in the top 100. At this point, don't worry about physics, start with the basics.

I know I'm scared, but so put it in a nutshell, what am I wrong in my arguments?

You are not even wrong. You basilisked yourself, as intelligent people are prone to do. You privileged one specific super-low-probability fear (being a Boltzmann brain) over a multitude of much more realistic scary scenarios (like that you are in a coma, drugged, high, hallucinating etc). Once scared, your mind is focused on this one scenario that it randomly picked from a long list. The one once privileged in these parts of the internet was being tortured through acausal trade or something. If you have OCD tendencies, as would be my guess, then letting go of what your brain latched on is really hard, and requires learning coping techniques that have a lot to do with psychology, and nothing with physics.

In what sense that I'm not even wrong? and why do boltzmann's brains have a very low probability? anyway i know i have ocd tendencies but it's really hard to live with
Maybe "not even wrong" is not the best way to put it. Still, I think you would do well to focus on learning to avoid self-basilisking due to OCD or potentially other neurodivergent issues, rather than asking why any particular fear is unfounded. I am not a doctor though.

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