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Jude_B comments on The map of ideas how the Universe appeared from nothing - Less Wrong

7 Post author: turchin 02 September 2016 04:49PM

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Comment author: Jude_B 19 September 2016 03:42:53PM 0 points [-]

I think we need to get clearer on what "why," "something" and "exists" mean.

For example, if you assume that numbers "exist", that is, you are willing to attach the descriptor "exist" to numbers, then you already have your answer: "Because numbers exist necessarily!"

Voila! End of story! Move over, folks, nothing(...) to see here.

Still, if you think that numbers are "something" and that they "exist," then it still doesn't answer why THE PHYSICAL world exists, or consciousness. I guess that now you can follow Tegmark's footsteps and say that everything is mathematics, and that's it. (But maybe there is a separate answer?)

So now (for Platonists) the "why" question is not why something exists, it is how to prove physical existence from the necessary existence of numbers or mathematical structures.

So like I said, before one tries to answer this question one first has to give some working definition as to what "why," "something" and "exists" mean.

Comment author: turchin 19 September 2016 11:09:45PM 0 points [-]

I think that "why" here represents our surprise about why Null hypothesis (nothing exists at all in Parfit words) is not true. "Why" is about missing part of knowledge and about feeling that something wrong with our model of the world. Why is also connected here with "how" question, as it should provide us with "Theory in everything", which explains, how exactly primordial nothingness evolved in observable set of physical laws.

I also think that "exist" and "something" is almost the same idea. "Something" can't be without "exist" and vica verse.

So the most problematic in your question is what is "existence". And if we will able to find the nature of existence we also will be able to find why something exist, it is almost two sides of one question.

One of the most consistent ways to define "existence" is to connect it with experience: If something exists, it is in my experience, or it could influence my experiences.

But in this case we postulate some form of observer as an axiom. I think that many rationalists may not like it. In this case all we have is only some hallucinations of primordial observer. This theory may be self consistent, but it seems that it doesn't coreleate with observable set of physical laws.

Another way to define "existence" is try replace it with idea of logical consequences. If A is true, than A exists. This definition help us to get rid of mystics of primordial observer, and also logically create mathematical universe.

What is your opinion about correct definition of "existence"?

Comment author: Jude_B 21 September 2016 06:33:12PM 1 point [-]

I guess you ask "why" when something is unobvious or unexpected.

The first one is relative, where obvious for a smart person might not be obvious to a less-smart one. So, like you said, it is not obvious why the null hypothesis does not obtain, and anyone who says that existence is obvious is fooling himself.

The second is less relative, for example, if a monkey randomly types Hamlet then it is unexpected, but if he just typed pure gibberish, it is not. Thus, a universe which is a totally chaotic will be more expected than a universe like ours (so not only need we ask why something exists, but why it is so ordered). However, I don't know if we can say that the null-hypothesis is more expected.

I guess, in a clumsy manner, I meant to say that the real question is what would a satisfying explanation be. Some people are satisfied with God, others with MUH, others with Suskind's landscape and others will never be.

Now, about "something" equal to existence. That's tricky, is a square circle something? Is a possible world something? If they are, do they "exist"?

I agree with you that the only type of existence that we are 100% sure about is our own (i.e. our consciousness). Now, if you are not a solipsist, then, as you said, you are willing to grant "existence" to things that you can interact with, but then would you deny it from causally independent realms of existence? Does a universe without observers, like the sound of the proverbial tree in the forest, really exist? I think Wheeler thought so, and I am sympathetic to that position, but who knows.

Furthermore, do the objects in our physical theories exist--like quarks, strings, other universes in Linde's chaotic realm--they might explain a lot, but their existence is always indirectly inferred or is a conclusion of some useful theory.

So to (sort of) answer your question, I don't think I can give an intensional definition of existence, but its extensional one will include consciousness; it might include other things but I think we'll need to know the intensional one first...

As for all logically consistent structures (or something like that) existing. Maybe, who knows. It's a bit like Lewis's and Tegmark's ideas, no? Also, I'm not an expert, but I think that theorems by Tarski(?) show that there isn't any universal notion of "Truth."

And what is "A"? A proposition? A sentence in first order logic? A sentence in set theory? A second order sentence?

What if A says about itself "I do not exist"? If it's true then it doesn't exist, if it is not then it does.

My head is starting to ache, so I'll better stop.

Cheers.

Comment author: turchin 22 September 2016 12:13:41AM 0 points [-]

I am trying to be bayesian in such complex questions. That means that I create a field of all possible hypethesis, and based on known evidence, corespondent field of probabilities of all hypothesis. Such approach will probably never result in one truth, that is in the situation where probability field is like (1,0,0,0,0) on field of (MUH, CUH, LUH, etc).

But we could gain knowledge about the topic without ever coming to one final truth. Creating more and more complex maps is an instrument to gain knowledge. I think that one approach which may work - is to create mathematical theory of qualia. If we do it, and we prove that qualia is a type of mathematical objects, we will get something like "MUH with qualia" as final theory.

The first thing in such theory should be idea that qualia can't depend on anything. Everything which explains red must be red. So they are like mathematical axioms. It also explain their ability to be self-born. So it explains how universe appear from nothing, but don't explain orderness of observations.

The second thing we have to do is to explain, how qualia are able to merge between themselves into experiences. We can't just say that there is sets of different qialia, as it would result into something like "qualia Bolzmann brains" dominations.

And even if we could explain how they are able to merge, we have to return to normality and explain how it all results in the observable universe with its QM laws. This could be most difficult part of all construction. (One way to start here is to see that there is direct connection between qualia and anthropic principle, and more, if we know types of qualia a being has, we could reconstruct types of its observations and laws of the universe he lives. E.g. if he has 2 dimensional color qualia he probably lives in 3 dimensional universe with some form of radiation.)

All I said above is just sketch of a theory which I hope to create some day, but which doesn't have high priority now.

Comment author: Jude_B 22 September 2016 11:15:20PM 1 point [-]

There's a guy named Donald D. Hoffman whom I saw on YouTube; unlike you, he is sort of "consciousness monist" (if I understand him correctly), that is, he claims that the most basic part of reality is consciousness and, in fact, reality is a network of relations between these basic particles.

I guess that if you can find some sort of an identity between this basic particle and a mathematical object we get your idea (If I understand your ideas correctly).

I also sort of remember him claiming that he could deduce the rules of quantum mechanics, but I'm not 100% sure.

You might want to check his ideas out.

Cheers

Comment author: turchin 22 September 2016 11:44:18PM *  0 points [-]

Thanks for lead. I think that I could be "conscious monist" after all, but I prefer not to use term consciousness, and use "qualia" as it is better defined.