ArisKatsaris comments on The Apparent Reality of Physics - Less Wrong

-3 Post author: ec429 23 September 2011 08:10PM

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Comment author: ec429 23 September 2011 09:52:07PM *  0 points [-]

Good objections, but I think they all have answers:

Of course it would, though it's underlying reality wouldn't be what we expect. (it might be a pointer in some program, instead of a collection of atoms)

But a pointer is information. At the physical layer, it's a configuration - when you say char *p=malloc(1); you haven't created an electron to sit in &p, rather you've configured existing electrons so as to have a pattern that is meaningful to one of your higher-level maps, but as a good reductionist you know that your higher maps don't represent anything ontologically basic about the territory.

As far as I know from any given perspective, existence is a binary quantity, something either is or isn't.

That's the point - I'm showing that the belief that 'existence' results from physical manifestation reduces to the absurdity that more physical manifestations of something means it exists more, which is nonsensical.

In Object-Oriented Programming, there's Classes which are a description of the instantiated objects, and there are the objects themselves, which you can do different things with than with the classes.

String a="5"; String b=a;

Does this make String("5") exist twice as hard? No; it doesn't even change whether it exists or not. It may be an object rather than a class, but it's still just a collection of information, which can be represented once, many times, or not at all, without ever changing the value of String("5").toInteger().

Again, how do you know there's no XML tag attached to the mathematics of our universe?

I don't know it, but such a tag would be epiphenomenal, and therefore it makes sense to assume it doesn't exist. If you're so sure that physical reality is manifest/instantiated, then how do you know, and why does it happen to follow regular mathematical laws? I think that believing in manifest physical reality is like believing in p-zombies (or, which comes to the same thing, dualistic consciousness).

The Tegmark IV hypothesis is exciting but I don't see how it's supposedly so self-proving as its proponents suggest.

It's not self-proving - at least, I don't claim it so - it's just simpler (shorter message length) to say "{equations}" than to say "mass-energy and space and time, which follow {equations}", and thus in the absence of evidence for the existence of manifest reality (which evidence I do not believe to be possible) a Bayesian, taking an Occamian prior, should conclude that the former is more likely than the latter. The only reason we mostly believe the latter is that, like Copenhagen, it came first.

EDIT: also, my views are distinct from (and were formed before I read) Tegmark IV; in particular his paper makes no mention of the concept of instantiation (and seems to me to be assuming that all Tegmark worlds are physically instantiated), and he wants to limit his hypothesis to computable structures, which I consider unnecessary and unjustified - I'm happy with the existence of structures so transfinite we can't even imagine them, perhaps because I'm a mathematician rather than a physicist.

Comment author: ArisKatsaris 23 September 2011 10:23:26PM *  2 points [-]

but as a good reductionist you know that your higher maps don't represent anything ontologically basic about the territory.

I know that -- because as a good reductionist I recognize that my map is a different portion of the territory, that portion of the territory which resides inside my head and which is merely correlated to the actual territory outside of my head.

But tsn't that the opposite of what you and Tegmark IV are saying: namely that the maps we call "equations" represent something ontologically basic about the whole of the territory?

That's the point - I'm showing that the belief that 'existence' results from physical manifestation reduces to the absurdity that more physical manifestations of something means it exists more, which is nonsensical.

I'd be careful what I'd call "nonsensical" when your argument instead must lead to the conclusion that things must exist even when they don't exist... This would be called nonsensical by many others.

I don't know it, but such a tag would be epiphenomenal

Epiphenomenalism is usually referring to something conceptual or cognitive (e.g qualia or consciousness or subjective experience) that doesn't have an influence on physical states.

You're instead talking about physical existence not having an influence on conceptual entities (namely the mathematical equations).

(shorter message length) to say "{equations}" than to say "mass-energy and space and time, which follow {equations}",

Yes, once you have the physical reality of a mouth and a keyboard (which happen to require mass-energy) to be able to say those equations, you can just say the "{equations}" --- namely you can transform a portion of the territory into an accurate map of the whole of the territory. But it still doesn't conclusively explain how the territory came to be.

Comment author: ec429 23 September 2011 10:55:06PM 2 points [-]

I recognize that my map is a different portion of the territory, that portion of the territory which resides inside my head and which is merely correlated to the actual territory outside of my head.

But the actual-territory is not (or at least, need not be) causally influenced by the territory inside your head that's implementing the map.

But tsn't that the opposite of what you and Tegmark IV are saying: namely that the maps we call "equations" represent something ontologically basic about the whole of the territory?

I can't speak for Tegmark, of course, but what I'm saying is that "equations" are the territory, and the stuff that looks to us like rocks and trees and people and the Moon is just a map.

I'd be careful what I'd call "nonsensical" when your argument instead must lead to the conclusion that things must exist even when they don't exist...

On the contrary, the conclusion is that things must exist even when they don't "exist" - where that quotation refers to some silly little savanna-concept we have in our brains, about rocks and trees and people and the Moon. Which don't exist.

Epiphenomenalism is usually referring to something conceptual or cognitive (e.g qualia or consciousness or subjective experience) that doesn't have an influence on physical states.

You're instead talking about physical existence not having an influence on conceptual entities (namely the mathematical equations).

That's because (in my model) the conceptual entities are the bedrock of the hierarchy, and physical existence is strongly analogous in this model to qualia in a physical-realist model. After all, "{equations}" and "rocks following {equations}" both give the same result for "value of X at time T", so the existence of rocks is epiphenomenal to the equations.

once you have the physical reality of a mouth and a keyboard (which happen to require mass-energy) to be able to say to the equations, you can just say "equations"

But a simulated me, existing only as information represented by electrons in a computer, could say "equations" just as loudly. So why couldn't a purely informational me, existing as unrepresented information, say "equations" too? Physical reality is a burdensome detail which doesn't add any explanatory power to your model; the claim that information needs to be represented in order for conscious entities contained within that information to exist seems to me to have no evidence backing it up, nor indeed to be capable of having such evidence, and therefore Occam demands that we frame our model in such a way as to make that claim inexpressible. It's rather like moving from configuration space to relative configuration space; unmeasurable claims become unreal.

But it still doesn't conclusively explain how the territory came to be.

It doesn't need to "come to be"; 'time' and 'causality' are parochial notions, concepts we can use to model things within our universe. Expecting the multiverse to obey them seems to me to be a Mind Projection Fallacy. A block universe just is.

Thanks for the insightful critique, by the way - it's helping me to understand the arguments better and see weak points that I wouldn't have noticed myself. I'm still not sure whether my theory is circular, nor whether I should care if it is.

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