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A Brief Explanation of Greg Egan’s Dust Theory

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Re: A Brief Explanation of Greg Egan’s Dust Theory

#101

Post by a1369209993 »

Reelin wrote: post #91
jbotz wrote: post #71

Earlier quoted context omitted.

> This theory leads to any possible existence existing, [...] This statement maybe superficially correct, but I interpret it differently. Every possible existence may exist, but not every imaginable existence. For something to exist in this manner, it has to be possible to generate it in a logically consistent manner from some initial conditions and simple rules, and while that allows for a "terrifying expanse of exi…

> Infinity != Everything More precisely, infinite sets come in different sizes. For example, there are provably more real numbers than natural numbers even though both sets are infinitely large. ( https://en.wikipedia.org/wiki/Aleph_number )

I think their point is more along the lines of "there are infinitely many (real or rational) numbers between zero and one, but none of them are equal to two".

Re: A Brief Explanation of Greg Egan’s Dust Theory

#102

Post by askvictor »

nkingsy wrote: post #87

Just finished Diaspora. It made me feel rather stupid, as the analogies it weaves throughout (as way to dumb it down I suppose) were sort of like reading the cliff notes. Okay 6 dimensions, ok 12 sure. And this one is 5 dimensions but they’re all sort of visible or something. But really it’s infinite dimensions and all that science proofing I skimmed was wrong. Great. I did love the artificial mind part in the beginn…

All of Egan's books make me feel stupid, but in the best possible way :) I always feel I'm getting half the picture but would need a PhD in whatever speciality he's focussing on in this book to get the whole thing, yet thoroughly enjoy every book all the same.

Permutation City is something of a different take on the artificial mind to Diaspora. Schild's Ladder deals also has the artificial mind theme, perhaps a bit closer to Diaspora, but with it's own take again.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#103

Post by drdeca »

pbhjpbhj wrote: post #92
KerrickStaley wrote: post #58

Here is an explanation of Dust Theory from Wikipedia: "[Dust theory states that] there is no difference, even in principle, between physics and mathematics, and that all mathematically possible structures exist, among them our physics and therefore our spacetime...The dust theory implies that all possible universes exist and are equally real, emerging spontaneously from their own mathematical self-consistency." I thi…

Not familiar with the concept, but how does it square with Godels Incompleteness theory, is any mathematical universe even possible?

There is no conflict.

An antidote to common misunderstandings of Gödel’s incompleteness theorems may be to understand Gödel’s completeness theorem.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#104

Post by quesera »

foobarbecue wrote: post #31
db48x wrote: post #11

Earlier quoted context omitted.

You'd probably like Neal Stephenson's Anathem. It's a Hemn Space argument.

Is that the one that had hundreds of pages of monks hanging around at the beginning? I got bored and couldn't make it through

That's the one. I thought it was great -- it's not unusual when reading an "epic era" Stephenson book to spend a lot of time wondering what story is being told.

But he's a great writer and if you enjoy his style, you usually are rewarded with two or three books of story by the time you run out of pages.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#105

Post by lifeformed »

vladTheInhaler wrote: post #42
codethief wrote: post #7

He lost me right in the second paragraph: > Because computation is sort of subjective, just a set of relations that can be usefully interpreted as representing a function, this seems to imply that the function you identify with can be interpreted as being simulated by any sufficiently complex set of relations. Can anyone explain? I'm already struggling with the premise: Why should computation be subjective in the fir…

If I understand correctly, it's not that the computation itself is subjective, but that the interpretation of the results is. Like how things are represented in lambda calculus - is this really an integer, or is it just a blob of function applications that has an interpretation consistent with being an integer? That part is subjective. Edit: to be more explicit, the parallel is "is that really a mind, or is it just a…

What's a real integer anyways, if not just a specific series of relationships between different entities?

Re: A Brief Explanation of Greg Egan’s Dust Theory

#106

Post by a1369209993 »

pbhjpbhj wrote: post #92
KerrickStaley wrote: post #58

Here is an explanation of Dust Theory from Wikipedia: "[Dust theory states that] there is no difference, even in principle, between physics and mathematics, and that all mathematically possible structures exist, among them our physics and therefore our spacetime...The dust theory implies that all possible universes exist and are equally real, emerging spontaneously from their own mathematical self-consistency." I thi…

Not familiar with the concept, but how does it square with Godels Incompleteness theory, is any mathematical universe even possible?

The closest GIT gets to being relevant is that some mathematical universes exist (or 'exist') that cannot be proven to exist. Alternatively - since Godel's Incompleteness Theorm is the same thing thing as the Halting Problem - some simulations that can't be proven valid (ie that each step of the simulation halts) are nonetheless valid.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#107

Post by [deleted] »

3pt14159 wrote: post #57
sxp wrote: post #6

This article doesn't actually explain Dust Theory to someone who hasn't read the book. I haven't found a good standalone explanation of the theory that explains it in a compact manner so my recommendation to people is to read the book. Permutation City is among my top 5 favorite books because I found Dust Theory so mind blowingly amazing from a philosophical standpoint. I haven't seen it discussed elsewhere outside t…

Almost a decade ago I independently invented the same idea. Discussion was here: https://news.ycombinator.com/item?id=2727750 It's a pretty simple theory, which I ultimately reject even to this day. If it were true, however, the expanse of existence is truly terrifying. This theory leads to any possible existence existing, short of maybe self-contradiction[0]. Well, so if that is true, then there exists a relation of…

[deleted]

Re: A Brief Explanation of Greg Egan’s Dust Theory

#108

Post by hgibbs »

Well yes, you could construe any physical object as having conciousness by having a sufficiently detailed/complex schema that assigns 'meanings' to each of its states.

But we all agree a rock is not conscious, so this definition doesn't pass the common sense test.

One mistake is then claiming that this usage of the word conciousness can be substituted for the commonplace usage in all situations. E.g. why don't we feel the same ethical obligation to a potentially conscious rock that we do to animals, humans and, arguably, seemingly intelligent entities?

For a nice exposition of this one can read chapter 2 of Gary Drescher's book 'good and real'.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#109

Post by mcguire »

"That is, for any random set of relations with enough complexity to represent a human mind, Egan claims, there exists an exotic encoding scheme that can interpret this set of relations as representing any arbitrary function, including the function that you would call “I”."

"There exists an X" is significantly different as a statement from "This X" (or "All X", for that matter).

Since I assume that solipsism is a fallicy, I don't find this philosophical position all that useful.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#110

Post by mcguire »

ajconway wrote: post #77
canjobear wrote: post #50

Very interesting to think about. Here's my interpretation of the argument: Suppose you have some system X whose dynamics are those of conscious agents in a world. For example, maybe X is the real world. Suppose that the agents in X really experience consciousness. Now suppose we apply some one-to-one function f to X, yielding Y = f(X). Then Y contains all the same information as X. So who's to say that the agents in…

If you believe in mathematical realism than the fact that there surely exists a mapping between a random set of data and a simulation with conscious agents in it, that should be enough.

Yours may be the finest argument for constructivism I have seen.
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