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Computation as a universal and fundamental concept

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Re: Computation as a universal and fundamental concept

#141

Post by jibal »

jibal wrote: post #94
jibal wrote: post #86

Earlier quoted context omitted.

I know what metaphysics is (and your description isn't accurate--science is a knowledge-producing method that doesn't depend on metaphysics in order to be meaningful), but that has nothing to do with my statement. And it's called "metaphysics" because Andronicus placed that volume after the "physics" volume when he organized Aristotle's writings.

I asked for proof of claims and I just get "it absolutely does" and a bunch more assertions, and word salad like "the validity of the scientific method is ultimately a metaphysical extension of our intuitions about inductive reasoning and causality" -- there's nothing "metaphysical" about it ... the scientific method is a disciplined application of an effective process of discovery. And '"Our intuitions" is why I sai…

> Your epistemic position is ultimately just as faith based as you claim faith in God etc.

This lie is so tiresome.

It's notable that science has a history of effectively producing confirmable fact whereas religion produces only falsehoods.

Re: Computation as a universal and fundamental concept

#142

Post by jibal »

Robotbeat wrote: post #121
jibal wrote: post #85

Earlier quoted context omitted.

> It’s not just an analogy or a coincidence that the word “entropy” is a word used in both physics and computer science (information theory). Shannon asked von Neumann what to call it, and von Neumann said "You should call it entropy, for two reasons: In the first place your uncertainty function has been used in statistical mechanics under that name, so it already has a name. In the second place, and more important,…

I’m aware of the von Neumann joke. There is, however, a direct equivalence between them derived from the 2nd Law of Thermodynamics. https://en.wikipedia.org/wiki/Landauer's_principle

Um, only the second part was a joke. The first part was confirmation of your statement that it's not just an analogy or coincidence ... and Shannon followed von Neumann's advice (not joke).

Re: Computation as a universal and fundamental concept

#143

Post by salutis »

nl wrote: post #78
sgt101 wrote: post #2

Computation has turned out to be a far more general concept than I think was imagined, up to the point that many computer scientists now seem to equate computation with the functioning of the universe. Recently it's been shown that there are real, physical processes which are undecidable (we cannot know if a latice of atoms has a spectral gap or not, we cannot determine if a specific particle in a fluid flow will rea…

Undecidable isn't uncomputable. "Computable" can mean probabilistic, and classical computers can function over probability distributions just fine.

This is incorrect. An undecidable problem is one for which no algorithm can compute the correct result for every given instance. Probabilistic classical computation is irrelevant here.

Re: Computation as a universal and fundamental concept

#144

Post by alfiedotwtf »

Robotbeat wrote: post #60
Diogenesian wrote: post #49

There are a lot of long comments basically saying what I am about to say so I will try to keep this brief: Computation is a metaphysically universal and fundamental concept, since metaphysics is (tautologically) the domain of humans and we use symbolic communication. So of course very general theories of symbolic processes (e.g. Turing machines) are pertinent to the symbolic methodology we use to understand scientifi…

This is a misconception. It’s more fundamental than that. There’s a fundamental connection between (Shannon) information theory and thermodynamics. The Landau Limit, whether blackholes can destroy information or not, quantum mechanics, etc. Information is actually tangible . It’s not just an analogy or a coincidence that the word “entropy” is a word used in both physics and computer science (information theory). Ther…

Thank you. I’ve been thinking about this for a while now and couldn’t express what I was thinking about… but when you linked information theory to thermodynamics, it clicked.

Given the quantum fields were collapsed in the early universe, I’m now wondering how information theory looked like during the different phases on the universe

Re: Computation as a universal and fundamental concept

#145

Post by pegasus »

voidhorse wrote: post #133
aeonik wrote: post #103

Earlier quoted context omitted.

I think you are prematurely dismissing something deeper here. The more I learn about the fundamental nature of the electron, probability in quantum mechanics, and the wave function in general... the more information being fundamental substrate makes sense. I'm not saying it is... just that it makes more sense the deeper you get.

Yeah, but my point is that "information" is not really a substantive concept. It is an abstraction. It is a useful technical tool. For the record, I am a nominalist when it comes to mathematics. Thinking that information is some "real thing" with meaning independent of theoretical context and interpreters is a definitely Platonisist perspective (the idea that our mathematical representations are not merely useful tec…

This stance is very tempting because it appears so straightforward and no-nonsense. But there are issues which undermine it in my mind. Because, at a closer inspection, it itself doesn't seem informative, in the end coming down to a question of semantics, i.e. how we define the word "reality". Which then determines whether it encompasses the realm of mathematics or not. I wonder what definition you favor, but the language you use points towards something like "the totality of all things" or "everything that's made from a physical substance". Yet platonists and other realists wouldn't argue that numbers are made from a substance as you imply.

Physical reality is a slippery thing. Yes, at the level of our daily life it all seems very solid and obvious, but inspecting that foundation revealed a bewildering world of relativity and uncertainty. And one of the most intriguing ways out of this bewilderment seems to be the "it from bit" trend in physics, which makes information the fundamental reality.

I personally don't feel the need to tie the notion of reality to physical phenomena. I prefer something more along the lines of Philip K. Dick's "reality is that which doesn't go away when you stop believing in it", or, as you put it, "something which exists independently of us". The fact that there are an infinite number of primes, is such a fact. Surely any alien civilization would know this fact. Maths doesn't go away when we look away, and neither does the notion of computation. Sure, Turing machines are a human construct, and there can be others as well. But the Church-Turing thesis speaks about how these constructs all ultimately describe the same underlying reality.

Re: Computation as a universal and fundamental concept

#146

Post by pegasus »

curiousest wrote: post #99
Robotbeat wrote: post #60

Earlier quoted context omitted.

This is a misconception. It’s more fundamental than that. There’s a fundamental connection between (Shannon) information theory and thermodynamics. The Landau Limit, whether blackholes can destroy information or not, quantum mechanics, etc. Information is actually tangible . It’s not just an analogy or a coincidence that the word “entropy” is a word used in both physics and computer science (information theory). Ther…

You can say things like, “In the domain of physics, X,” “Assuming the scientific method, X,” or “Assuming the premises of logic, X.” But “computation is a fundamental aspect of the universe”, in the way it's being understood in this thread (as opposed to the article) does not remain within any of those frameworks. It makes a claim about reality as a whole. Once you make that kind of universal claim, all the assumptio…

The Church-Turing thesis (the fact that all models of computation we've been able to come up with are equivalent) gives the necessary weight to that claim.

Re: Computation as a universal and fundamental concept

#147

Post by lmpdev »

ChrisGreenHeur wrote: post #74
BirAdam wrote: post #73

Earlier quoted context omitted.

I’ve always hated the use of the word “information” in relation to things like spin. Information and order are effects of human perception and preference. They exist as abstractions in the mind and not in reality.

Best way to show this is to implement information in multiple physical substrates. Make a book out of paper and make it out of clay. Same information. The physical substrate doesn’t matter.

A parallel concept to this is from functionalism/theory of mind in Philosophy is that of Multiple Realisability

Re: Computation as a universal and fundamental concept

#148

Post by lmpdev »

amwet wrote: post #79
ianburrell wrote: post #72

Earlier quoted context omitted.

Spacetime isn't quantized as far as we know. We don't know since we don't have quantum gravity or ability to probe Planck scale. Quantum fields are continuous, it is excitations in the field, particles, that are quantized.

Ah, I thought we didn’t have strong evidence either way. Regardless, I shouldn’t have stated spacetime quanta so matter-of-factly. I just have an easier time conceptualizing if I treat everything like hypervoxels and that leaked in.

The answer is we don’t know for certain

There are even some philosophers/mathematicians who attest to finitism (they’re not mainstream, though), but if correct would undermine our idea of fields and continuous structures more broadly

Re: Computation as a universal and fundamental concept

#149

Post by GoblinSlayer »

pegasus wrote: post #145
voidhorse wrote: post #133

Earlier quoted context omitted.

Yeah, but my point is that "information" is not really a substantive concept. It is an abstraction. It is a useful technical tool. For the record, I am a nominalist when it comes to mathematics. Thinking that information is some "real thing" with meaning independent of theoretical context and interpreters is a definitely Platonisist perspective (the idea that our mathematical representations are not merely useful tec…

This stance is very tempting because it appears so straightforward and no-nonsense. But there are issues which undermine it in my mind. Because, at a closer inspection, it itself doesn't seem informative, in the end coming down to a question of semantics, i.e. how we define the word "reality". Which then determines whether it encompasses the realm of mathematics or not. I wonder what definition you favor, but the lan…

"it from bit" is just "shut up and calculate", positivism. There are no bits in physics, and no boolean phenomena.

Re: Computation as a universal and fundamental concept

#150

Post by GoblinSlayer »

Diogenesian wrote: post #91
jibal wrote: post #86

Earlier quoted context omitted.

I know what metaphysics is (and your description isn't accurate--science is a knowledge-producing method that doesn't depend on metaphysics in order to be meaningful), but that has nothing to do with my statement. And it's called "metaphysics" because Andronicus placed that volume after the "physics" volume when he organized Aristotle's writings.

Science absolutely does depend on metaphysics. Most famously: the validity of the scientific method is ultimately a metaphysical extension of our intuitions about inductive reasoning and causality. There is no scientific proof that the scientific method is valid. ("Our intuitions" is why I said metaphysics is tautologically the domain of humans. This is essentially Kant's philosophical legacy: science will describe w…

Isn't it obvious that scientific method is fallible? It's just statistically better than pure reason, which should be possible to demonstrate statistically. It's a product of trial and error, and there were many errors, I don't think there's much metaphysics there.
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