The map of ideas how the Universe appeared from nothing
post by turchin · 2016-09-02T16:49:26.148Z · LW · GW · Legacy · 41 commentsContents
How we going to solve the problem? Where we can get information? Most probable explanations Usefulness of the question The structure of the map Best reading: None 41 comments
There is a question which is especially disturbing during sleepless August nights, and which could cut your train of thought with existential worry at any unpredictable moment.
The question is, “Why does anything exist at all?” It seems more logical that nothing will ever exist.
A more specific form of the question is “How has our universe appeared from nothing?” The last question has some hidden assumptions (about time, universe, nothing and causality), but it is also is more concrete.
Let’s try to put these thoughts into some form of “logical equation”:
1.”Nothingness + deterministic causality = non existence”
2. But “I = exist”.
So something is wrong in this set of conjectures. If the first conjecture is false, then either nothingness is able to create existence, or causality is able to create it, or existence is not existence.
There is also a chance that our binary logic is wrong.
Listing these possibilities we can create a map of solutions of the “nothingness problem”.
There are two (main) ways in which we could try to answer this question: we could go UP from a logical-philosophical level, or we could go DOWN using our best physical theories to the moment of the universe’s appearance and the nature of causality.
Our theories of general relativity, QM and inflation are good for describing the (almost) beginning of the universe. As Krauss showed, the only thing we need is a random generator of simple physical laws in the beginning. But the origin of this thing is still not clear.
There is a gap between these two levels of the explanation, and a really good theory should be able to fill it, that is to show the way between first existing thing and smallest working set of physical laws (and Woldram’s idea about cellular automata is one of such possible bridges).
But we don’t need the bridge yet. We need explanation how anything exists at all.
How we going to solve the problem? Where we can get information?
Possible sources of evidence:
1. Correlation between physical and philosophical theories. There is an interesting way to do so using the fact that the nature of nothingness, causality and existence are somehow presented within the character of physical laws. That is, we could use the type of physical laws we observe as evidence of the nature of causality.
While neither physical nor philosophical ways of studying the origin of the universe are sufficient, together they could provide enough information. This evidence comes from QM, where it supports the idea of fluctuations, which is basically ability of nature to create something out of nothing. GR theory also presents idea of cosmological singularity.
The evidence also comes from the mathematical simplicity of physical laws.
2. Building the bridge. If we show all steps from nothingness to the basic set of physical laws for at least one plausible way, it will be strong evidence of the correctness of our understanding.
3. Zero logical contradictions. The best answer is the one that is most logical.
4. Using the Copernican mediocrity principle, I am in a typical universe and situation. So what could I conclude about the distribution of various universes? And from this distribution what should I learn about the way it manifested? For example, a mathematical multiverse favors more complex universes; it contradicts the simplicity of observed physical laws and also of my experiences.
5. Introspection. Cogito ergo sum is the simplest introspection and act of self-awareness. But Husserlian phenomenology may also be used.
Most probable explanations
Most current scientists (who dare to think about it) belong to one of two schools of thoughts:
1. The universe appeared from nothingness, which is not emptiness, but somehow able to create. The main figure here is Krauss. The problem here is that nothingness is presented as some kind of magic substance.
2. The mathematical universe hypothesis (MUH). The main author here is Tegmark. The theory seems logical and economical from the perspective of Occam’s razor, but is not supported by evidence and also implies the existence of some strange things. The main problem is that our universe seems to have developed from one simple point based on our best physical theories. But in the mathematical universe more complex things are equally as probable as simple things, so a typical observer could be extremely complex in an extremely complex world. There are also some problems with the Godel theorem. It also ignores observation and qualia.
So the most promising way to create a final theory is to get rid of all mystical answers and words, like “existence” and “nothingness”, and update MUH in such a way that it will naturally favor simple laws and simple observers (with subjective experiences based on qualia).
One such patch was suggested by Tegmark in respond to criticism of MUH, a computational universe (CUH), which restricts math objects to computable functions only. It is similar to S.Wolfram’s cellular automata theory.
Another approach is the “logical universe”, where logic works instead of causality. It is almost the same as mathematical universe, with one difference: In the math world everything exists simultaneously, like all possible numbers, but in the logical world each number N is a consequence of N-1. As a result, a complex thing exists only if a (finite?) path to it exists through simpler things.
And this is exactly what we see in the observable universe. It also means that extremely complex AIs exist, but in the future (or in a multi-level simulation). It also solves the meritocracy problem – I am a typical observer from the class of observer who is still thinking about the origins of the universe. It also prevents mathematical Boltzmann brains, as any of them must have possible pre-history.
Logic still exists in nothingness (or elephants could appear from nothingness). So a logical universe also incorporates theories in which the universe appeared from nothing.
(We could also update the math world by adding qualia in it as axioms, which would be a “class of different but simple objects”. But I will not go deeper here, as the idea needs more thinking and many pages)
So a logical universe seems to me now a good candidate theory for further patching and integration.
Usefulness of the question
The answer will be useful, as it will help us to find the real nature of reality, including the role of consciousness in it and the fundamental theory of everything, helping us to survive the end of the universe, solve the identity problem, and solve “quantum immortality”.
It will help to prevent the halting of future AI if it has to answer the question of whether it really exists or not. Or we will create a philosophical landmine to stop it like the following one:
“If you really exist print 1, but if you are only possible AI, print 0”.
The structure of the map
The map has 10 main blocks which correspond to the main ways of reasoning about how the universe appeared. Each has several subtypes.
The map has three colors, which show the plausibility of each theory. Red stands for implausible or disproved theories, green is most consistent and promising explanations, and yellow is everything between. This classification is subjective and presents my current view.
I tried to disprove any suggested idea to add falsifiability in the third column of the map. I hope it result in truly Bayesian approach there we have field of evidence, field of all possible hypothesis and
This map is paired with “How to survive the end of the Universe” map.
The pdf is here: http://immortality-roadmap.com/universeorigin7.pdf
Meta:
Time used: 27 years of background thinking, 15 days of reading, editing and drawing.
Best reading:
Parfit – discuss different possibilities, no concrete answer
http://www.lrb.co.uk/v20/n02/derek-parfit/why-anything-why-this
Good text from a famous blogger
http://waitbutwhy.com/table/why-is-there-something-instead-of-nothing
“Because "nothing" is inherently unstable”
http://www.bbc.com/earth/story/20141106-why-does-anything-exist-at-all
Here are some interesting answers
https://www.quora.com/Why-does-the-universe-exist-Why-is-there-something-rather-than-nothing
Krauss “A universe from nothing”
https://www.amazon.com/Universe-Nothing-There-Something-Rather/dp/1451624468
Tegmark’s main article, 2007, all MUH and CUH ideas discussed, extensive literature, critics responded
http://arxiv.org/pdf/0704.0646.pdf
Juergen Schmidhuber. Algorithmic Theories of Everything
discusses the measure between various theories of everything; the article is complex, but interesting
http://arxiv.org/abs/quant-ph/0011122
ToE must explain how the universe appeared
https://en.wikipedia.org/wiki/Theory_of_everything
A discussion about the logical contradictions of any final theory
https://en.wikipedia.org/wiki/Theory_of_everything_(philosophy
“The Price of an Ultimate Theory” Nicholas Rescher
Philosophia Naturalis 37 (1):1-20 (2000)
Explanation about the mass of the universe and negative gravitational energy
https://en.wikipedia.org/wiki/Zero-energy_universe
41 comments
Comments sorted by top scores.
comment by buybuydandavis · 2016-09-04T20:03:25.690Z · LW(p) · GW(p)
“Why does anything exist at all?”
I lose no sleep over this. I think people who do are just confused by language.
I'd say that if you examine your concept of "why", you find it presupposes existence.
Replies from: Jude_B, entirelyuseless, turchin, torekp↑ comment by Jude_B · 2016-09-19T15:20:01.460Z · LW(p) · GW(p)
So when you ask, "Why did Sherlock Holmes tell Watson that...?"
You assume that Holmes exists?
Also, when you ask why some complicated theorem in number theory is true, you are basically asking for a proof from first principles (say Peano Arithmetic), you don't need to assume that numbers exist (which would make you a Platonist).
↑ comment by entirelyuseless · 2016-09-06T02:20:57.661Z · LW(p) · GW(p)
I said as much in one of my replies to turchin. But that doesn't mean that the question has no answer.
↑ comment by turchin · 2016-09-05T12:09:51.993Z · LW(p) · GW(p)
But some people do like Tim Urban http://waitbutwhy.com/table/why-is-there-something-instead-of-nothing
I think that it is overkilling argument, as it may be applied to almost any question. Why Sun looks like a circle? Why we value human existence?
This "why" expresses some kind of lacking knowledge or confusion, but not exactly appropriate wording to really describe what is going on.
So our inability to find adequate wording for something as already incorporated into "why".
comment by der (DustinWehr) · 2017-03-08T00:23:54.664Z · LW(p) · GW(p)
Your note about Gödel's theorem is confusing or doesn't make sense. There is no such thing as an inconsistent math structure, assuming that by "structure" you mean the things used in defining the semantics of first order logic (which is what Tegmark means when he says "structure", unless I'm mistaken).
The incompleteness theorems only give limitations on recursively enumerable sets of axioms.
Other than that, this looks like a great resource for people wanting to investigate the topic for themselves.
Replies from: turchin, turchin↑ comment by turchin · 2017-03-08T19:24:33.008Z · LW(p) · GW(p)
I would also add just to remember the idea, that logical paradoxes inside logical universe may look like logical black holes, and properties of these black holes may have surprising similarities with actual black holes.
Logical black holes may attract lines of reasonings, but nothing could come out of them, and in the middle they have something where main laws contradict each other the same way as physical laws are undefined in the gravitational singularity of astronomical black hole.
Epistemic status: crazy idea.
comment by Viliam · 2016-09-04T22:42:46.991Z · LW(p) · GW(p)
I feel like the answer is something like "existence is relative". As an intuition pump, if you read a story, the characters in the story do exist relative to each other, but they don't exist relative to you.
This idea is typically used together with an assumption that somewhere "at the top" is some kind of top-level existence (for example God), that creates all lesser existences by simulating them. However, this answer has two problems: First, it doesn't actually answer anything; it's circular. We got from "why is there this universe instead of nothing" towards "why is there the top-level something instead of nothing". Second, it assumes that the top-level existence has some mysterious essence, which suggests confused thinking.
Instead, I think there is no such thing as the top-level existence, no mysterious substance of reality. Instead, all realities are... without any inherent existence. Words fail me here; I am simply trying to say that none of these realities is real relative to some outside standard, simply because there is no such thing as an ourside standard. A more poetic way would be to say that all realities are potential; they are stories without any external reader (or sometimes stories with an external reader that also exists only in a story without a reader; or sometimes in an infinite chain which is no more or less real than any other infinite chain of stories).
However, a reality is real relative to itself. Something like a zero divided by zero -- there is nothing outside this reality that would make this reality real, but this reality is real enough to itself (and therefore to us, who exist within it). Other realities are unreal to us, and we are unreal to them.
Of course this whole argument avoids the question of measure -- if there are many realities, what is the experience of an average observer in an average reality, and how are the averages even calculated. I think the answer is that the more simple universes (with smaller Kolmogorov complexity) have higher measure, but I have no idea how something like that could be proved.
Replies from: turchin↑ comment by turchin · 2016-09-05T11:41:58.807Z · LW(p) · GW(p)
The relation thing is really appealing. But as Tegmark said all mathematical universe is about relation, so in a nutshell relation universe is Math universe hypothesis (MUH). If we use Kolmogorov complexity as the measure, it results in Computable universe (CUH). But still most problems of MUH and СГР are unresolved here, and most of the are still about measure and our mediocracy.
Because measure is the same spark of existence which we tried to explain from the start, and if we need it at the end, we didn't explained anything.
For example, in CUH only computable universes exist. But still it would favour very complex AIs with infinitely large minds and field of perception.
It also favour somekind of dust minds which I would name "axiomatic brains". We could postulate any complex mind as an axiom, and it is enough to its existence, and from such minds most will be very complex and very random.
There is also a problem with measure in math world - in it can't be several copies of something. There is no many copies of number 151. It is just one number, even if it appear many times in different ways of calculation. So something can't be "rare".
My attempt to patch it was "logic universe", in which all relations are logic consequences of non existence. In it all very complex thing also exist but they should be logical consequences of simpler things. And now it starts to look like our universe which starts from simple singularity and evolves towards the zoo of very complex possible AIs.
Replies from: Viliam↑ comment by Viliam · 2016-09-06T11:59:06.347Z · LW(p) · GW(p)
Because measure is the same spark of existence which we tried to explain from the start, and if we need it at the end, we didn't explained anything.
You're right. There is still missing the explanation for why the universes with higher measure (however defined) should be the ones we are more likely to exist in.
Just randomly guessing, maybe it's related to simulation: the universes with lower Kolmogorov complexity will more often be simulated by something in other universes. Unlike the typical anthropocentric simulation hypothesis (strawmanned as: "every advanced civilization will want to simulate 20/21 century homo sapient on Earth, because we are the coolest ones"), let's assume that things will be simulated for various reasons, sometimes not even because of some conscious decision, just as a side-effect of some laws of physics in some universe... and the more simple a universe is, the more often it will get simulated for completely random reasons.
But I'm not too proud to admit that I am completely confused here, heh.
Replies from: turchin, turchin↑ comment by turchin · 2016-09-08T12:40:33.669Z · LW(p) · GW(p)
I got the following ideas about the spark.
The laws of our universe are such that they enable creation of something out of nothing. QM with its fluctuations and GR with its singularity describe the world which appeared from nothing.
Not any set of possible laws allow it. These laws are math objects, but they allow creation of something from nothing (most laws don’t do it). So only a subset of all math universe is able to create things. It creates natural cutoff between all possible math objects - only rather simple laws allow such type creation.
I would illustrate it with following example: Newtonian laws are not describing appearing of matter from nothing. So while purely Newtonian universe is conceivable and mathematically possible, it doesn't exist as it existence would contradict its own laws.
But there is another set of laws: QM+GR - it describes how something could appear from nothing, and so existence of something doesn't contradict these laws.
I think that there are other possible combinations of laws which internally consistently explain how something could appear from nothing. But such set may be very small, as more complex laws results in more contradictions.
So we have very natural cutoff in math universe - lets name it Generational Universe hypothesis (GUH). It said that only those universes exist which laws describes how they appear from nothing and also don't have contradictions. GUH has stronger restrictions than CUH.
Logical universe hypothesis (LUH), which said that if nothing exists than 1 doesn't exist and if 1 doesn't exist than 2 doesn't exist is also similar GUH, as it describes the generation of math objects. But it doesn't explain properties of our universe.
Replies from: Viliam↑ comment by Viliam · 2016-09-11T20:46:12.362Z · LW(p) · GW(p)
such set may be very small
Still infinite probably.
But I like the idea how you consider whether the laws themselves allow creation of a new universe. So, it seems like the Tegmark mathematical universe provides "templates" for universes, but only a subset of these "templates" will actually create a working instance.
↑ comment by turchin · 2016-09-06T12:17:17.827Z · LW(p) · GW(p)
I also thought that we may be in in the lowest level of infinitely complex multilevel simulation (and of any possible simulation in math world).
But it still don't help with measure problem, because many similar things in math world is just one thing. So if our world is simulated many times it doesn't change its measure. Like no matter how many times we wrote 25 it will not change distribution of prime numbers in the set of natural numbers.
But also random choosing doesn't work with infinite sets. We can't choose random prime number, or it will be infinitely long. I think we could dig in this way.
Replies from: turchin↑ comment by turchin · 2016-09-06T13:46:24.308Z · LW(p) · GW(p)
A. One possible counterargument here is following. Imagine that any being has rank X, proportional to its complexity (or year of birth). But there will be infinitely many beings which are 10X complex, 100X complex and so on. So any being with finite complexity is in the beginning of the complexity ladder. So any may be surprised if it is very early. So there is no surprise to be surprised.
But we are still should be in the middle of infinity, but our situation is not so - it looks like we have just enough complexity to start to understand the problem, which is still surprising.
B. Another similar rebuttal: imagine all being which are surprised by their position. The fact that we are in this set is resulted only from definition of the set, but not from any properties of the whole Universe. Example: All people who was born 1 January may be surpised that their birthday coincide with New Year, but it doesn't provide them any information about length of the year.
But my birthday is randomly position inside the years (September) and in most testable cases mediocracy logic works as predicted.
comment by Soothsilver · 2016-09-03T05:44:15.995Z · LW(p) · GW(p)
Wow, thank you very much! I would have thought most LessWrongers would answer the question "Why does anything exist?" with the answer "That question does not make sense."
I didn't know there was such a range of options.
Replies from: turchin↑ comment by turchin · 2016-09-03T09:26:27.793Z · LW(p) · GW(p)
I think that most LessWrongers would vote for mathematical universe. The idea of timeless mathematical manyworld universe was presented in sequences. When I first meet it I was attracted to its simpleness and beauty.
But now I found that where is reasonable objection to it, like expected complexity problem. Most math objects should be extremely complex, and it is not what we see.
Replies from: entirelyuseless, qmotus↑ comment by entirelyuseless · 2016-09-03T17:32:08.804Z · LW(p) · GW(p)
Yes. It has the same problem as pure dust theory. I would expect a life where objects are jittering, floating into the air, and so on, just enough to preserve a continuous life and experience but without killing me.
But that doesn't happen, so those explanations are false.
Replies from: turchin↑ comment by turchin · 2016-09-03T21:59:08.373Z · LW(p) · GW(p)
Unfortunately I recently come to conclusion that this argument against dust theory is flawed.
Because thoughts of dust mind are random and are not causally dependent from his experiences. So he in 50 per cent cases will think that his environment is OK and in 50 per cent that it is random and strange. While his environment is 99.99 per cent cases is strange.
The best example here is our thoughts during dreams. Sometimes during a dream we think that the dream landscape is normal and sometimes we think that it is bizarre. But in the morning we understand that it was bizarre in most cases! This happens because our mind is not able to calculate bizzareness during the dream.
(I don't claim that we are Boltzmann brains after all, but we have to find another proof)
Replies from: entirelyuseless↑ comment by entirelyuseless · 2016-09-04T00:57:48.805Z · LW(p) · GW(p)
I don't see any reason to think that the thoughts of a dust mind would be random in that particular way, namely thinking that the world is ok in 50% of the cases.
Replies from: turchin↑ comment by turchin · 2016-09-04T09:12:01.755Z · LW(p) · GW(p)
If dust mind has random experiences he should also has random thoughts. Most dust minds will not interested in the question about orderness of their reality. But in the small subset of those who interested, the answers will be random.
And if you see mess in my room now you may think that it is rather random )))
Replies from: entirelyuseless↑ comment by entirelyuseless · 2016-09-04T15:29:50.276Z · LW(p) · GW(p)
A dust mind isn't the same as a Boltzmann brain. A dust mind would be an interpretation of random facts as a mind -- e.g. you could interpret the movement of dust particles on the road outside as a mind, if you give a sufficiently complicated interpretation. But you may be right that we should expect that mind to have random experiences and random thoughts. I am just saying that I don't see why randomness would necessarily lead to a 50/50 probability between those two -- it isn't clear that they are equal regions of the probability space. It could be like saying that rolling two dice randomly should give you a 12 half the time.
Replies from: turchin↑ comment by turchin · 2016-09-05T10:35:55.684Z · LW(p) · GW(p)
Yes they are not the same by their origin, but (probably) the same in distribution of their possible experiences.
In the dice example only in 1 case of 12 the "environment" will be not random, but the mind who looks on dices is also has random thoughts about dices, depending not form the dices results, but form a random coin.
So in 6 cases he will think that they a random (and they random), in 5 cases that they not-random, but they are random and in 1 case that they are not random and they are not random.
In short we can't believe our thought process in determining randomness of enivronment, because if the dust mind our thought process is full of errors.
But I still think that I am not random dust mind, and I use other lines of thoughts to prove it.
First is that any random mind is equal to some real mind (if any exist) and by process similar to quantum (big world) immortality will be immediately "copied" into real one.
The second is that there is lines of sequences in the space of all possible mind, which connect similar mind-states and these lines tend to converge to more stable ones. I suggested this idea last year to a guy here on LW who was really afraid that he is dust-mind and he was satisfied.
Some other ideas exisе about it, I should make a map about BB and dust minds. ))
↑ comment by qmotus · 2016-09-03T12:36:29.510Z · LW(p) · GW(p)
MUH has a certain appeal, but its problems as well, as you say (and substituting CUH for MUH feels a little ad hoc to me), and I fear parsimony can lead us astray here in any case. I still think it's a good attempt, but we should not be too eager to accept it.
Maybe you should make a map of reasons for why this question matters. It's probably been regarded as an uninteresting question since it is difficult (if not impossible) the test empirically, and because of this humanity has overall not directed enough brainpower to solving it.
Replies from: turchin↑ comment by turchin · 2016-09-03T21:45:59.383Z · LW(p) · GW(p)
If we able to find the answer, it will provide as with exact knowledge of the nature of reality and solve all remaining questions about qualia and consciousness. The last will help to solve the problem of the nature of mind and personal identity and help with creation of AI and uploading. So, it will help us create safe AI and reach immortality. That is very practical goals.
The answer will also include a Theory of everything, which will provide us with complete understanding of physics.
So to have the answer is useful.
We also have some evidences for possible solution. In preambula to the map I listed 5 types of possible evidences. But non of them is definitive.
comment by scarcegreengrass · 2016-09-19T18:13:10.787Z · LW(p) · GW(p)
turchin, i just want to say that i really like these idea-catalog infographics.
Replies from: turchincomment by entirelyuseless · 2016-09-04T16:43:38.180Z · LW(p) · GW(p)
By the way, I strongly disagree with many of your colorings. For example, it seems very likely that human beings are incapable of knowing the answer in any clear way, but you classify that as red. Likewise, "existence exists by definition" seems to me definitely true no matter what the rest of the answer is, but you classify that as red. And you have "existence is an illusion" as green, which I and most people would put as red. There are a bunch of others too.
Replies from: turchin↑ comment by turchin · 2016-09-05T12:07:41.177Z · LW(p) · GW(p)
Thank you for your input. Probably I should gave explanation to any estimation I did.
May be we are incapable but we can't know it now. That is we are incapable to know that we are incapable until very large research of the topic will be done. So it is too early to give up. And any way we could create at least a field of plausible hypotheses.
"Existence exists by definition" doesn't explain anything as we didn't provide this definition of "existence". So it looks like sophism or show stopper in style "God is eternal". So it looks like explanation but is not explanation at all.
In case "existence is illusion" I show my belief that we need explanation of subjective experience reality and nature of qualia, and that such explanation also will have ontological meaning.
But it is great that other people have different opinions, because we could later use some kind of voting mechanism to try to get "market knowledge". ))
Replies from: entirelyuseless↑ comment by entirelyuseless · 2016-09-05T14:06:56.383Z · LW(p) · GW(p)
- I agree with you that we don't know in advance what we can or can't know, and that we shouldn't give up. That is why I just said it is "very likely" and in particular "incapable of knowing the answer in any clear way," not of knowing the answer at all. It seems to me that this is not judging in advance, but we actually have pretty good evidence that we can't know in such a clear way, namely that people have tried this for a long time and failed, at least in knowing clearly, even if maybe not in knowing at all.
But even there, I agree that we should keep trying and shouldn't take that as a reason for giving up at all.
-2. Anything you can mention either exists, or it doesn't. That means that any answer to "why does anything exist rather than nothing" must exist, or not exist. If it exists, it is not an explanation, since the answer in this case presupposes something existing. If it does not exist, it cannot be an explanation for existing things, since there is no such thing (as the thing that doesn't exist.)
This is not sophistry: it actually proves that in some sense there is no explanation. But it only shows that there is no explanation in a certain way, not there is no explanation in any way. And your coloring suggested to me that you consider it more reasonable for the final explanation to be something non-existing, rather than something existing. That seems unlikely to me -- it seems quite a bit more likely that the final explanation will be something that exists. If that is true, it will have to be something that exists "by definition," since it won't have something else explaining why it exists. It is true that that could not be a perfect explanation, but we already know (from the argument above) that there is no perfect explanation.
-3. I agree with you about qualia, I am just saying it is very very likely that there are other things besides qualia.
Replies from: turchin↑ comment by turchin · 2016-09-05T14:49:11.192Z · LW(p) · GW(p)
I have another example in obviously true explanation, which looks like this one: "Causality exist without cause". It is almost the same as "existence exist". I was satisfied with it for a long time.
But now I think we should make them more rigorous to work. We may ask what kind of objects "can't non exist". And starting from it we could name several types of objects which exist anyway (Logic, math, and probably observer and qualia). And now we could try construct from them our reality.
So my point is that we should give definition of existence and see how it works in our case.
Maybe I should consider yellow there and give this explanation.
comment by Jude_B · 2016-09-19T15:42:53.418Z · LW(p) · GW(p)
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.
Replies from: turchin↑ comment by turchin · 2016-09-19T23:09:45.673Z · LW(p) · GW(p)
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"?
Replies from: Jude_B↑ comment by Jude_B · 2016-09-21T18:33:12.443Z · LW(p) · GW(p)
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.
Replies from: turchin↑ comment by turchin · 2016-09-22T00:13:41.107Z · LW(p) · GW(p)
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.
Replies from: Jude_B↑ comment by Jude_B · 2016-09-22T23:15:20.048Z · LW(p) · GW(p)
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
Replies from: turchincomment by [deleted] · 2016-09-04T16:48:41.656Z · LW(p) · GW(p)
There is a distinct possibility that information on the nature of the big bang simply does not survive to the present day.
Replies from: turchin↑ comment by turchin · 2016-09-05T11:46:08.421Z · LW(p) · GW(p)
It surely should not survive, as in the time when something appeared from nothing there was not any information channels able to convey such information. But we still may try to find explanations to fact of existence. But many thinks that it is fruitless project, first was Immanuel Kant.
comment by entirelyuseless · 2016-09-03T17:35:33.678Z · LW(p) · GW(p)
You could also have included eliminativism about meaning along with "nothing exists." The eliminativist would say that all words and sentences are meaningless, and therefore none of them are true, and therefore there is no true explanation nor any meaningful question to answer.
Replies from: turchin↑ comment by turchin · 2016-09-03T21:52:21.280Z · LW(p) · GW(p)
It is in the map in the large section of "meaningless". The main counterargument here is that our words only arrows which points on a problem, but not the problem itself. We could imagine some examples where our wording is non-perfect, but the problem is real.