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Comment author: Viliam 29 May 2016 07:58:05PM 0 points [-]

Well, if you get some mathematics explaining why universe destruction results in exactly the numbers known from quantum physics, then maybe it gets interested.

Sorry, I have no specific path to follow, other than to first study quantum physics on its own (all the equations with the complex numbers etc.) before inventing your own theory of why it is what it is. First get to know what, then speculate about why. Otherwise you are at risk of getting quantum physics wrong, and then inventing reasons for your wrong understanding of the quantum physics, which is a lose/lose situation (either you can't find a good explanation, or you succeed to find an "explanation" for something that is actually not true). If you get familiar with the standard university-level quantum physics, then your hypotheses get the chance to be actually useful.

Making a wrong hypothesis is the inevitable risk, but seeing people waste energy inventing explanations for something that is not true, that's quite sad. (I am now thinking on one long lecture I attended at Mensa, where a guy "disproved theory of relativity" by proposing a theory that was obviously wrong for trivial reasons; it actually predicted that particles would move quite differently parallel to some absolute space axes x,y,z than diagonally. Since there are no obvious "straight" and "diagonal" directions in our universe, his hypothesis was completely wrong regardless of whether Einstein was right or wrong about some technical detail.)

Comment author: PeterCoin 07 August 2016 06:00:27AM 0 points [-]

So yeah. the gold standard is. of course. scientific prediction. My idea is very far away from such a thing! I actually do have some background in quantum mechanics (I have a physics minor :P) and at one point actually did have some understanding of Hamiltonian Operators and eigenstates and bra-ket notation. However that's a far cry from the sort of needed mathematics to really understand the implications of what I'm talking about (this is why they say a little knowledge is a dangerous thing)! What I do have is enough knowledge to tentatively pose that my idea doesn't contradict what we've actually seen in experiments (so I don't think it's trivially wrong).

I'm not too worried about proposing a possible explanation first then asking what it can explain. That may seem like a backwards way of doing things, but it might be a way to approach problems from a different angle. My guess is (having not read much scientific biography it's hard to say) there were probably some scientists who developed the key ideas of their breakthroughs prior to completing formal training in their field. Besides, it's a lot more effort for me to learn all this stuff then to just ask the question on on Internet forum!

I'm also not worried about becoming that Mensan. That dude put too much emotional stakes into being right about that. He is completely emotionally invested in the correctness of his idea and his own brilliance over Einstein. I'm keenly aware of the fact that I'm just some dude throwing some half-baked idea onto an Internet forum. I'm not at all worried if people think it's crazy or wrong. And I'm not worried if it is wrong! What worries me more is if people don't think it's worth the time of day or is completely uninteresting. That would make me sad but not hugely sad, just kinda sorta sad. My contention is merely the idea is interesting enough to take somewhat seriously.

Comment author: PeterCoin 29 May 2016 08:14:26AM 0 points [-]

I'm confused here: You seem to be analyzing a troubleshooting process. How exactly did the troubleshooting process fail? I can see that there's some criticisms of what was done. But I don't see how this troubleshooting process resulted in disaster.

Comment author: gilch 06 January 2016 08:52:29PM *  1 point [-]

Has this ever been seriously considered? (I’ve done some homework but undoubtedly not enough).

This idea is hardly new here. See Simulation, Consciousness, Existence by Hans Moravec, Permutation City by Greg Egan, and the Quantum Physics Sequence by our own Yudkowsky (especially the Many Worlds parts with the Ebborians, starting with Where Physics Meets Experience) and Robin Hanson's mangled worlds, which might help to explain some of the odd probabilities we find in quantum mechanics.

Comment author: PeterCoin 29 May 2016 07:16:48AM 0 points [-]

These are some very good links. I'm still digesting them. Thank you!

I've at least gave them all a once over (with the exception of Permutation City which awesome as it looks suffers from my general failure to incorporate fiction into my life) but definitely need to dig deeper. There's so much cool stuff out there that I'm still scratching the surface on.

Hans Moravec's Mind Children, I think comes closest to my argument. but stops short of stating that quantum suicide type scenarios might skew our understanding of physical law.

Anyways I'm just curious as to what else you've seen in a similar vein.

Comment author: Viliam 24 May 2016 07:26:27AM 0 points [-]

An obvious target is the counterintuitive statistics that make quantum mechanics so spooky.

Please don't go this way, this is an obvious dead end. Trying to explain something you don't understand by proposing even weirder hypothesis with completely unpredictable consequences... yeah, it's tempting, but you could equally say that "maybe magic is real... and that would explain the double-slit experiment". It kinda would, but only because it could explain literally everything.

Comment author: PeterCoin 29 May 2016 04:56:56AM 0 points [-]

I get the sort of unrestrained woolly thinking that comes from a diet of too much insight porn and an overtrusting one's own ideas. Let me assure you that I don't particularly trust my suspicion here. My aim is to see if it is a good idea or not and if it is a good idea see how far it goes. I figure if someone can provide an extremely compelling argument as to why it's not true then that itself would probably be pretty interesting!

On the subject of quantum mechanics my intent is not to explain a mystery with another mystery fill it with secret sauce and revel in the mysticism. I detest such a thing. Since my idea rests on a specific properties of the "true" interpretation of quantum mechanics (one where our experience of time branches) I sort of view partaking in that fight as a necessary endeavour.

My imediate aim is much more focused. I'm specifically referring to the counterintuitive nature of probability in situations like Bell's theorem. There is a strong link in mathematical structure between Bell's and conditional probability which has its own famous counterintuitive probability puzzle (The Monty Hall Porblem). I believe the possibility of universe destroying events can exhibit the same sort counterintuitive subjective experiences. However I have yet to really flesh it out in a more rigorous way.

I apologize if that last paragraph comes off a bit as word salad. Part of why it's hard to explain is because probability in a branching-time scenario is sort of an illusion. In MWI a quantum coin flip both heads and tails are actually observed. The perception of a 50/50 chance is "merely" a subjective experience. Which means you have to be very deliberate about what you're talking about; it gets tricky to talk clearly about it.

Anyways what excites me more is when you said "please don't go this way" you sort of imply that there's another way that you find to be better. I'd really like to know your thoughts as to where you'd like to see it go. I fully expect to go down paths where completely reasonable people will ask "what the hell is that dude thinking? and I fully expect to sometimes ask myself later "what the hell was I thinking?"

"Those are my principles, and if you don't like them... well, I have others." - Groucho Marx

Comment author: Viliam 24 March 2016 07:43:26AM 2 points [-]

If this hypothesis ("99% of universes get destroyed every microsecond, but we don't notice because of anthropic principle") would be true, the question is what exactly are those universe-destroying events, and whether something can increase or decrease their probability.

Because if the probability of the universe-destroying event depends on some factor X, then we couldn't observe the destruction of universe per se, but we could imagine statistically weird behavior of X. For example, if we flip a coin, and the outcome of head means that universe gets destroyed with 99% probability, but the outcome of tails means that universe gets destroyed with 99.9% probability, from our point of view it would seem like an imbalanced coin where the head falls about ten times more likely than tails.

Problem is, we wouldn't necessarily perceive this as "statistically weird", but rather as completely normal, because that's how it always was. From our point of view, it would be just another law of physics: "If you flip a coin, the outcome is head ten times more likely than tails; that's how the coins behave, duh".

So maybe at this moment we could start suspecting any fact about our universe, or any law of physics, as a statistical artifact of the "fragile universe hypothesis".

Something like: "Why do neutrinos have such a small mass?" "Maybe there is a reason why the mass has to be non-zero, but maybe also more massive neutrinos generate universe-destroying events more frequently, which is why we find ourselves in a universe with neutrinos having small mass."

Or: "Why is universe expanding?" "Each collision of particles has a non-zero probability of generating a universe-destroying event, and this is why we are more likely to find ourselves in a universe where the frequency of collisions is decreasing; i.e. an explanding universe."

Comment author: PeterCoin 24 May 2016 07:01:53AM *  0 points [-]

This is exactly the suspicion I have. The "real" physical laws could be quite different from the "experienced" physical laws. If this idea is correct physicists are only getting a small piece of the story of how the universe really operates.

It seems to me that this sort of behavior could (with sufficient refinement) provide an account for some of the more bizarre aspects of physical law. An obvious target is the counterintuitive statistics that make quantum mechanics so spooky.

It would also be place where physicsists could stuff their physics - extra degrees of freedom to explain the regularities we observe in nature. Perhaps instead of tiny curled dimensions of string theory we can stuff some of that physics into the details of a sort of subatomic brinksmanship.

(sometimes I wonder [not too seriously] if this could explain why certain things aren't - why we don't see dark matter, or where there are no free quarks or magnetic monopoles - maybe when they crop up the world as we know it ceases to be)

A pernicious difficulty is tying our experience of probability to what is actually going on. Ultimately some sort of self-selection accounting must occur. This is where we come up against sleeping beauty type problems and need to question some strongly held intuitions.

And that's where I start getting confused (not that there aren't other confusing aspects to this)!

I generally take that confusion to be a good sign. If there wasn't some dangerous conceptual waters everyone would wade in. What I don't see any real no go as to why the universe couldn't be this way.

Comment author: PeterCoin 09 September 2015 01:35:44AM *  0 points [-]

Median expected behavior is simple which makes it easy to calculate.

As an electrical engineer when I design circuits I start off by assuming that all my parts behave exactly as rated. If a resistor says it's 220+10% Ohms then I use 220 for my initial calculations. Assuming median behavior works wonderfully in telling me what my circuit probably will do.

In fact that's good enough info for me to base my design decision on for a lot of purposes (given a quick verification of functionality, of course).

But what about that 10%? What if it might matter? One thing I do is called worst case analysis https://en.wikipedia.org/wiki/Tolerance_analysis#Worst-case

This is the exact opposite of what you're proposing! I look for the cases where everything is off by the greatest amount possible and in the way that combines to form the worst possible outcome. If my circuit has 2 220+10% ohm resistors I'll consider the cases where both are 242ohms, both are 198ohms and even the bizarre cases where one is 198ohms and the other 242ohms. I do that because if I know my circuit will function under those circumstances, then only when the resistors are out of tolerance (and I can blame someone else) there's a problem.

In my view, average expected utility is the true metric. But there are circumstances where it's easier and cheaper to ignore the utility of anything other than the median case, and there are circumstances where it's easier and cheaper to ignore the utility of anything other than the worst cases.

Comment author: Squark 29 August 2015 07:13:02PM *  1 point [-]

I'm digging into this a little bit, but I'm not following your reasoning. UDT from what I see doesn't mandate the procedure you outline. (perhaps you can show an article where it does) I also don't see how which decision theory is best should play a strong role here.

Unfortunately a lot of the knowledge on UDT is scattered in discussions and it's difficult to locate good references. The UDT point of view is that subjective probabilities are meaningless (the third horn of the anthropic trilemma) thus the only questions it make sense to ask are decision-theoretic questions. Therefore decision theory does play a strong role in any question involving anthropics. See also this.

But anyways I think the heart of your objection seems to be "Fragile universes will be strongly discounted in the expected utility because of the amount of coincidences required to create them". So I'll free admit to not understanding how this discounting process works...

The weight of a hypothesis in the Solomonoff prior equals N 2^{-(K + C)} where K is its Kolomogorov complexity, C is the number of coin flips needed to produce the given observation and N is the number of different coin flip outcomes compatible with the given observation. Your fragile universes have high C and low N.

...but I will note that current theoretical structures (standard model inflation cosmology/string theory) have a large amount of constants that are considered coincidences and also produce a large amount of universes like ours in terms of physical law but different in terms of outcome.

Right. But these are weak points of the theory, not strong points. That is, if we find an equally simple theory which doesn't require these coincidences it will receive substantially higher weight. Anyway your fragile universes have a lot more coincidences than any conventional physical theory.

I would also note that fragile universe "coincidences" don't seem to me to be more coincidental in character than the fact we happen to live on a planet suitable for life.

In principle hypotheses with more planets suitable for life also get higher weight, but the effect levels off when reaching O(1) civilizations per current cosmological horizon because it is offset by the high utility of having the entire future light cone to yourself. This is essentially the anthropic argument for a late filter in the Fermi paradox, and the reason this argument doesn't work in UDT.

Lastly I would also note that at this point we don't have a good H1 or H2.

All of the physical theories we have so far are not fragile, therefore they are vastly superior to any fragile physics you might invent.

Comment author: PeterCoin 30 August 2015 07:49:20PM 0 points [-]

I'll dig a little deeper but let me first ask these questions:

What do you define as a coincidence?

Where can I find an explanation of the N 2^{-(K + C)} weighting?

Comment author: Squark 23 August 2015 06:28:20PM 1 point [-]

Hi Peter! I suggest you read up on UDT (updateless decision theory). Unfortunately, there is no good comprehensive exposition but see the links in the wiki and IAFF. UDT reasoning leads to discarding "fragile" hypotheses, for the following reason.

According to UDT, if you have two hypotheses H1, H2 consistent with your observations you should reason as if there are two universes Y1 and Y2 s.t. Hi is true in Yi and the decisions you make control the copies of you in both universes. Your goal is to maximize the a priori expectation value of your utility function U where the prior includes the entire level IV multiverse weighted according to complexity (Solomonoff prior). Fragile universes will be strongly discounted in the expected utility because of the amount of coincidences required to create them. Therefore if H1 is "fragile" and H2 isn't, H2 is by far the more important hypothesis unless the complexity difference between them is astronomic.

Comment author: PeterCoin 26 August 2015 12:06:56AM 0 points [-]

I'm digging into this a little bit, but I'm not following your reasoning. UDT from what I see doesn't mandate the procedure you outline. (perhaps you can show an article where it does) I also don't see how which decision theory is best should play a strong role here.

But anyways I think the heart of your objection seems to be "Fragile universes will be strongly discounted in the expected utility because of the amount of coincidences required to create them". So I'll free admit to not understanding how this discounting process works, but I will note that current theoretical structures (standard model inflation cosmology/string theory) have a large amount of constants that are considered coincidences and also produce a large amount of universes like ours in terms of physical law but different in terms of outcome. I would also note that fragile universe "coincidences" don't seem to me to be more coincidental in character than the fact we happen to live on a planet suitable for life.

Lastly I would also note that at this point we don't have a good H1 or H2.

Comment author: PeterCoin 25 August 2015 06:08:07AM 0 points [-]

A few brainstormy ideas:

Survival/Sustenance - Food/Water/Shelter/Safety

Humor - Jokes/Comedy

Intimacy - Feeling emotionally connected/Physical Affection/Proximity

Validation - Positive Feedback on emotions/feeling understood/feeling that one is good and one matters

Comment author: HungryHobo 24 August 2015 09:23:42AM 2 points [-]

My objection is that it's irrelevant: It doesn't provide any useful information or anything that should guide your behavior because if every possible scenario is played out there's little difference between choosing to go for chemo and jumping off a bridge.

We're stuck with 1 subjective timeline. The other trousers of time aren't really relevant to us.

Comment author: PeterCoin 25 August 2015 05:38:06AM *  0 points [-]

I'm not quite grasping what you're trying to get it here. Please do elaborate and clarify!

When you say "It's irrelevant" and "it doesn't provide any useful information or anything that should guide your behavior" what are you referring to?

Choosing to go for chemo and jumping off a bridge should have different results, The difference between the two results would be the basis for the decision. I don't see how fragile universe hypothesis or MWI should undermine that.

As for the relevance of other timelines, I have four answers:

  1. MWI allows for quantum interactions with other timelines which means they're directly relevant

  2. MWI provides for multiple future timelines for me, despite the fact these future mes will not have a "me-ness" relationship with each other. All future versions of me are relevant to current me.

  3. Exploring this concept may result in theoretical predictions that are testable and eventually provide pragmatic benefits

  4. I would like to understand what exists and why. I would like the Truth regardless of pragmatic benefits associated with it,

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