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Shut up and calculate: an extreme mathematical universe

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Re: Shut up and calculate: an extreme mathematical universe

#131

Post by goatlover »

eli_gottlieb wrote: post #128
goatlover wrote: post #126

Earlier quoted context omitted.

Colors, smells, pains, etc. are not part of the mathematical or physical description, so you can't simply dismiss the problem of qualia by labelling it as dualism. Where do the colors, tastes, feels come from? What sort of math would result in those experiences? Here's another problem. You know about the physical/mathematical properties of the world by abstracting away from our experience of a world with color, sound…

>Colors, smells, pains, etc. are not part of the mathematical or physical description, so you can't simply dismiss the problem of qualia by labelling it as dualism. Where do the colors, tastes, feels come from? What sort of math would result in those experiences? Predictive coding in the interoceptive and control networks of the brain, actually. Sure, it doesn't explain everything , but it pretty well dispels the int…

How do you get anything other than likely correlation from "Predictive coding in the interoceptive and control networks of the brain", and what does it have to do with physics or math? At most, you've provided a biological basis for consciousness. But why would any of that result in color, pleasure, etc?

Re: Shut up and calculate: an extreme mathematical universe

#132

Post by eternalban »

westoncb wrote: post #49

It baffles me that people ignore the fact that they have subjectivity when making these claims. It makes a certain amount of sense since science itself aims to remove any taint of subjectivity in its practice, so folks who want to be thoroughly 'scientific' in other aspects of their lives (e.g. their personal philosophies of reality) carry over over this ideal. But it's also a contradiction since science scientific m…

> the idea that reality is made of math is one untestable hypothesis among many whose probabilities of correctness each approach zero by dint of their many peers.

I would like to (gently) challange the assertion that all untestable hypotheses are "peers" of (neo)Platonic notions. What sets mathematics apart is this: https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.htm...

Re: Shut up and calculate: an extreme mathematical universe

#133

Post by westoncb »

eternalban wrote: post #132
westoncb wrote: post #49

It baffles me that people ignore the fact that they have subjectivity when making these claims. It makes a certain amount of sense since science itself aims to remove any taint of subjectivity in its practice, so folks who want to be thoroughly 'scientific' in other aspects of their lives (e.g. their personal philosophies of reality) carry over over this ideal. But it's also a contradiction since science scientific m…

> the idea that reality is made of math is one untestable hypothesis among many whose probabilities of correctness each approach zero by dint of their many peers. I would like to (gently) challange the assertion that all untestable hypotheses are "peers" of (neo)Platonic notions. What sets mathematics apart is this: https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.htm...

Hey eternalban, I am familiar with that article. I posted something else here which I think explains why I find it insufficient for the author's uses (Tegmark, not Wigner):

> imagine some complex 3d object changing in time. Now imagine it's wrapped in a kind of net, like you see in 'wireframes' in computer graphics. If that complex 3D object is our universe, I see math as like that wrapping wireframe: there is a strong correspondence of some kind, and it covers the full extent of what's out there in some sense, but there are still gaps and extents into other directions etc. which are not math (or any form of human description).

I agree with you though, that it should be set apart from many more absurd hypotheses because of the additional merit it has—although for the specific question of whether reality is literally comprised of mathematics (rather than aspects of it being accurately describable by mathematics), it's a binary question, true or false, and while in some sense it's closer than the others, as far as I can tell it still lacks justification.

Edit: I should also add that my jab about probabilities approaching zero etc. etc. was more kind of a joke/flourish which probably could've been left out :)

Re: Shut up and calculate: an extreme mathematical universe

#134

Post by jonnybgood »

Houshalter wrote: post #119
followmeon wrote: post #38

If our reality consists of mathematical programs and the multiverse theory holds, then the theory of everything is a simple incrementing binary counter. Every possible binary string is ran on a Turing machine in a different universe. The halting problem (endless loops) is sidestepped by being contained to a single universe. Also, apparently our universe got lucky as we get to live in an ordered universe, and not diss…

I think you've confused the representation with the computation. Sure maybe that binary number could represent a universe state in some encoding. But there's no computation happening to it. It's static. >I believe that mathematics is a mental construct, mathematics does not exist without brains Brains evolved through natural selection to survive in the universe we exist in. Ideas similarly "evolved" to be good at mod…

> If there are two apples on the ground, and two more fall of a tree, then there are four apples on the ground. This is true whether or not a human is there to observe it and count them.

I don't know about that. How close do the apples have to be to number them? If two apples are within inches and another a mile away, is there two apples or three apples? Define ground. Is it dirt? And dirt of what? If two apples are on Earth and one apple on Mars, is there two or three apples on the ground? What does it even mean to number things? What is a number?

My point is that it takes a human brain for establishing definitions, axioms, and conditions. Only after these have been established can we do math.

Re: Shut up and calculate: an extreme mathematical universe

#135

Post by naasking »

westoncb wrote: post #89
titzer wrote: post #80

Earlier quoted context omitted.

> It baffles me that people ignore the fact that they have subjectivity when making these claims. Do they? Everyone is entitled to their unquestioned assumptions as long as they state them outright and describe their parameters. I have yet to see dualists (which ultimately is at the base of this whole line of argumentation) admit that they posit subjective experience _without evidence_, since they equate asking quest…

> The fact remains that no entity can successfully prove to another entity that it has inner experience, so how would proving you have subjectivity to _your own mind_ work? If you are trying to 'prove' subjectivity, in the sense of providing an argument for it, then you are missing the point: you already experience it directly by definition, so there is nothing to prove. > This is a bizarre and unsupportable statemen…

> If you are trying to 'prove' subjectivity, in the sense of providing an argument for it, then you are missing the point: you already experience it directly by definition, so there is nothing to prove.

I can also perceive that glasses of water magically break and reconstitute pencils, in what we now know to be an optical illusion. "Self-evident" observations stand only so long as they are consistent with all other observations. The premise that subjectivity exists is not consistent with everything else we know without introducing additional structure to the universe that has no purpose but to stroke our egos. Therefore, it should be discarded.

Re: Shut up and calculate: an extreme mathematical universe

#136

Post by naasking »

namelost wrote: post #51
hackinthebochs wrote: post #41

Earlier quoted context omitted.

I mean in the logical sense. If reality could contain logical contradictions then that would mean reality isn't rule-based, which means unconstrained randomness, no information, no meaning, etc.

But the contradiction is in the mathematical model not reality. Even a totally random universe follows some kind of distribution, which can then be modelled (which is exactly what QM is).

> But the contradiction is in the mathematical model not reality.

He's assuming a mathematical model that faithfully represents reality, hence "reality can't contain contradictions". We're not going to one day find a contradiction and vanish in a puff of logic, the ultimate model of reality will be contradiction-free.

Re: Shut up and calculate: an extreme mathematical universe

#137

Post by naasking »

westoncb wrote: post #43
Santosh83 wrote: post #35

An interesting article addressing this from Sabine Hossenfender: http://backreaction.blogspot.in/2007/10/mathematical-univers... Her more recent article (review of Max Tegmark's book) also comments on the same subject: http://backreaction.blogspot.in/2017/11/book-review-max-tegm...

This (the universe is 'made' of math) seems to me like the most egregious error in the general outlook of contemporary scientifically-minded people—and one I made myself for many years. If you really consider the issue closely, you'll see it depends on not overlooking certain dark corners of it which you can sort of ignore and assume to not contain contradictions—but they're there! And once you see them, it's hard to…

> If you really consider the issue closely, you'll see it depends on not overlooking certain dark corners of it which you can sort of ignore and assume to not contain contradictions—but they're there! And once you see them, it's hard to unsee them: what in the world would it mean for a desk to 'made' of mathematics—it's nonsensical.

What does it really mean to "exist" at all? It's equally undefined. This question is either problematic for every metaphysics, or none of them.

A desk is not "made" of mathematics any more than the words you're reading right now are "made" of electrons. What matters for existence is the relationships between mathematical structures. In this case, the relationship of your mind perceiving a desk is identical regardless of whether your mind and the desk are mathematical structures or some non-mathematical matter.

And once you accept that isomorphism, it's an easy step to a type of Platonism/mathematical monism because it's so unproblematic as a philosophy of mathematics. And once you're there, you have the mathematical universe.

Re: Shut up and calculate: an extreme mathematical universe

#138

Post by naasking »

gfodor wrote: post #59
eref wrote: post #30

Earlier quoted context omitted.

Tegmark's Mathematical Universe Hypothesis (MUH) is actually pretty much a computational theory of the universe. It basically makes the assumption that there exists somewhere the simplest process imaginable: One that counts through and runs all mathematical formulas which includes all programs, which, in turn, includes all (computable) universes. This assumption explains why our universe is oddly complex: If all univ…

I didn't take Tegmark's argument to be a computational theory. I took it to be an inductive one based upon the trend of the physics over the last decades towards the more and more generified multiverse theories. Ultimately, you land on a model where all consistent mathematical representations of a reality exist. At that level of abstraction, there is no where to go: it is the limit of the induction. There's a rather…

> Ultimately, you land on a model where all consistent mathematical representations of a reality exist. [...] IIRC there are no arguments about computation or what underlying medium(s) are involved, it seems like a separate question.

These are actually related by Goedel's incompleteness theorems and the Curry-Howard isomorphism. Computation and mathematics are inextricably linked.

The Computable Universe is a necessary restriction on the mathematical universe hypothesis to avoid accepting inconsistent universes.

Re: Shut up and calculate: an extreme mathematical universe

#139

Post by yorwba »

goatlover wrote: post #131
eli_gottlieb wrote: post #128

Earlier quoted context omitted.

>Colors, smells, pains, etc. are not part of the mathematical or physical description, so you can't simply dismiss the problem of qualia by labelling it as dualism. Where do the colors, tastes, feels come from? What sort of math would result in those experiences? Predictive coding in the interoceptive and control networks of the brain, actually. Sure, it doesn't explain everything , but it pretty well dispels the int…

How do you get anything other than likely correlation from "Predictive coding in the interoceptive and control networks of the brain", and what does it have to do with physics or math? At most, you've provided a biological basis for consciousness. But why would any of that result in color, pleasure, etc?

How would anybody ever get anything other than likely correlation?

Re: Shut up and calculate: an extreme mathematical universe

#140

Post by naasking »

otakucode wrote: post #68
klank wrote: post #45

Earlier quoted context omitted.

That's an odd definition of chaotic systems you are using. It's not so much that chaotic systems can not be calculated but instead that enough precision of starting conditions can't be obtained to ensure an accurate result (for example, highly non-linear systems). The double pendulum system is a perfect example where computation is simple yet the system is still chaotic.

I think it's an odd definition you are using. Chaos depends upon the sensitivity to those initial conditions, not what those initial conditions ARE. You do not need actual physical objects to see this. Conjecture that a double-pendulum system starts in a perfectly real-number-valued mythical reality where spacetime is perfectly continuous (a fiction). Now predict what state the system will be in at a bunch of 'close…

> You'll have to chop it off at some point. That's OK. That's what error bars are for. Just keep going and keep track of your error. Oops, you'll find that your error grows larger than the prediction itself with remarkable speed! THAT is the chaos.

If this were true, it should be trivial to prove by observation that we're not in a mathematical universe, or that physics is not computable, even in principle. As far as I understand, physics as we know it is widely acknowledged to be computable, albeit with exponential slowdown on classical computers.

By the Bekenstein bound and other thermodynamic constraints, a finite region of space necessarily contains a finite amount of information, or it would collapse into a black hole, ergo physics is at worst a finite state machine. So where's the disconnect?

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