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To someone like me, who believes that the universe is, must be, fundamentally a computer, the actual academic paper is hardly any better. Whatever the paper is
by taliesinb 6y ago
To someone like me, who believes that the universe is, must be, fundamentally a computer, the actual academic paper is hardly any better. Whatever the paper is doing is not describing any kind of computational process. It's a mille-feuille of semi-rigorous mathematical abstraction that sounds far more like a kind of liturgical incantation than a description of the software our universe is running.
That's not to say it is definitely not useful! It could be that, for some bizarre reason, reading the mathematical tea leaves of our current incomplete (and incoherent) theories might well yield insight into post-quantum physics. I do doubt it though.
- btilly 6y agoTo someone like me, who believes that the universe is, must be, fundamentally a computer... Why do you believe that?
- Enginerrrd 6y agoIt'd be hard for it not to be yet remain consistent with observations and conservation laws. Depends what you mean though. Define "computer".
- krastanov 6y agoSee this sibling comment for context https://news.ycombinator.com/item?id=24948188 https://news.ycombinator.com/item?id=24948188 The definition you are looking for is very well established and intensely studied in physics and theoretical computer science. This is a good place to start a wikipedia exploration of the topic: https://en.wikipedia.org/wiki/Church%E2%80%93Turing_thesis https://en.wikipedia.org/wiki/Church%E2%80%93Turing_thesis
- taliesinb 6y agoBecause I don’t think infinite amounts of information, and uncomputable numbers, exist. They are fantasies, and relatively recent ones at that. Unfortunately those fantasies came to dominate 20th century mathematics, and in the guise of string theory obtained a death grip on fundamental physics. Fortunately a new generation of smart people, with intuitions honed on computers, is well placed to capitalize on this arbitrage opportunity.
- taliesinb 6y agoHeartening to see that unusual perspectives and opinions are rewarded with downvotes.
- krastanov 6y agoI suspect the downvotes are due to (1) the lack of intellectual humility and (2) misrepresentation in your comments. Plenty of physicists agree that uncomputable numbers are unphysical and the idea that infinite information density can not exist is in no way new or controversial (it is pretty much the starting point for the holographic principle, one of our main paths to a theory of everything). They are beautiful ideas worth discussing, but you used your knowledge of them to disparage people and fields which it seems you only have passing familiarity with.
- dcow 6y agoYes. It is dogmatic, not scientific, to suggest that a paper is worthless because the authors didn’t frame their argument under some set of axioms you just really identify with, conceptually.
- creata 6y ago> those fantasies… in the guise of string theory obtained a death grip on fundamental physics What? The real numbers, with all the uncomputable reals included, are used in every corner of physics, not just in string theory. There is no treatment of calculus (with any semblance of popularity) that does not feature the usual real line.
- TheOtherHobbes 6y agoNothing in physics has infinite precision. Math is an abstraction - which is to say a stylised representation - and while you can imagine processes and representations with infinite precision, that level of precision is metaphysical. This confuses Platonists who seem to believe that differential equations really exist - somewhere. But that's like arguing that you will clock up air miles by zooming around Google Maps. The set of operations you can perform on representations of reality is in no sense identical to the set of operations you can perform on reality itself. If this still isn't obvious, try to differentiate a rock.
- h0l0cube 6y agoIn defence of the idea, if all physics is found to have a logical and mathematical basis, then doesn't all physical expression and interaction become computation?
- sudosysgen 6y agoCouldn't it be the reverse? Couldn't computation be the closest approximation to pure expression and interaction? Seems to me that this is more natural. Also, I will bet 500$ that no one will be able to prove that all physics has a logical and mathematical basis within my lifetime :)
- h0l0cube 6y agoI bet the same. I'm not sure that hard determinism could ever be proven, even if it were the case.
- krastanov 6y ago"Computable" is a bit more strict than "logical and mathematical". We can define many perfectly consistent processes with perfectly consistent "observable values", which are inherently uncomputable (as in, there is no algorithm, even an inefficient one, that runs on Turing machines, capable of calculating the observable). Here is my favorite example: https://en.wikipedia.org/wiki/Chaitin%27s_constant https://en.wikipedia.org/wiki/Chaitin%27s_constant
- h0l0cube 6y agoI guess much of what I'm saying counts on hard determinism, and computation that isn't limited to what can be achieved with boolean logic. I'm talking out my ass here a little, but I picture quantum annealing as a form of computation where quantum physics effects are the actual execution engine.
- krastanov 6y agoQuantum effects are still things we can simulate on a Turing machine with a program that halts (just inefficiently slow given our current knowledge of complexity theory). Bringing in quantum effects does not make things uncomputable.
- simonh 6y agoStephen Wolfram takes that view too, but it seems like a fairly narrow lens to peer at the universe through. I suspect it may be true, but that doesn't even mean it's necessarily particularly useful for solving many classes of problems. In fact, are there any actual problems in Physics that have been solved by this approach? Lots of things are true that aren't much use. Much of science, including physics doesn't describe computational processes. Does that make most of science and physics equally useless?
- Maha-pudma 6y agoI'm not sure what to make of this comment. I'm not going to pretend I understand any of this at anything short of an extremely superficial level but you argument sounds like something a religious fundamentalist might say; just insert their belief system. "To someone like me, who believes that the universe is, must be, fundamentally a construct of god, the actual academic paper is hardly any better. Whatever the paper is doing is not describing any kind of god process... sounds far more like a kind of liturgical incantation than a description of how god is running our universe." I might be wrong, my understanding is limited, but you shouldn't dismiss something because it doesn't fit with you beliefs; you beliefs may be wrong g.