8 ms·

The Universe as a Computer

49 points by dwighttk 2y ago

dwighttk 2y ago
48(!) possible meanings of the term
mjburgess 2y ago
In the end, the problem with the claim is that if it is true then 'computer' is defined so loosely as to be uninformative; as soon as you add plausible conditions, it seems obviously false. According to the best physics, the universe: isnt programmable; doesn't evolve deterministically; isnt described by functions over integers; isn't electronic; doesnt transmit power through programmable operation; isn't abstract; doesnt have causal powers through mere arrangements of parts; .. and so on. Whatever it could mean, "computer" here is a strange term. I've no idea why people are so keen on it. I take it to be a sort of humean-idealist-passivist theory: the world is an abstract set of discrete states that are just mere arrangements with no necessary connections; there is only pattern in these discrete states; these patterns are abstract and can be realised by mere number alone. This is roughly somehting like an early 20th C. logicial positivist view, which was somewhat influential -- but it's wholey false, and throw out in scientific practice
- optimalsolver 2y ago
  >doesn't evolve deterministically Isn't that still debated?
  - titzer 2y ago
    Not really. The best models that we have to explain measurable physical phenomenon are wave equations from quantum mechanics that describe probably distributions. There have been proposals for nearly a century that a deterministic model underlies this, but they have to contend with observed phenomenon and inconveniences like Bell's Theorem that suggest that our universe just isn't deterministic. That said, we don't have a unified theory of the universe. General relativity, the dark matter question, and quantum mechanics have not been unified into any mathematical theory. All of those theories are pretty weird, mathematically. And we have no efficient way to simulate on classical computers the models that we do have. We don't live in a billiard ball universe. It's a CS fantasy that evaporates as soon as you start doing experiments on matter and energy in the actual universe we are in.
    - mjburgess 2y ago
      Yes, the biggest problem with this mere mechanistic picture is why anything should move at all. The csci view is essentially a divine command one: the machine runs because of it's 'program' which is somehow external to the machine. But this is a metaphor/illusion for programmable devices like electronic computers, which breaks down for the actual universe. The universe must be inherently dynamical, ie., not mere discrete states that change by rules, but properties whose nature is to interact with the world... This is why the abstract mathematical conception of "computer" cannot describe anything physical: mathematical objects do not have temporal properties; they do not change. This leads to the illusion, for electric devices, that the change is extrinsic to the physics of the system since we can specify the algorithm (somewhat) abstractly. But it isnt.. your pieces of meat, are in the end, the causal power which moves the liquid crystal, electric field, etc.
      - fellowmartian 2y ago
        I think this a caricature or at least a shallow view of computationalism. Nobody is claiming that the universe is a computer of the same kind as the ones we have. Instead, I think, it claims that the universe has to necessarily be computational in order to be real - everything has to be computational to be real, otherwise how can it ever be implemented. On your "divine command" bit: I don't think any theory has a good claim on the ultimate ontology of reality, so I don't see how one view is better than another. It's all some kind of divine command at the moment. Computationalism at least constrains the necessary properties the divine must have.
        titzer 2y ago
        > everything has to be computational to be real But that's just circular logic. It begs the question as to what is "computational" and what is "mathematical". E.g. Tegmark has good points in the "Mathematical Universe" that describe possible interpretations of what it means to be mathematical. But how is computation different than math? I'd argue that computation is primarily stateful, logical, and (mostly) deterministic with a clear flow of time, whereas mathematical models are often time-reversible (as most, if not of QM is), stateless, and not necessarily "logical" in the sense of relating finite symbolic quantities. Rather mathematical models happily relate infinite series, manifolds, surfaces, high-dimensional spaces, they talk about fields and operate on functions, etc.
- madisp 2y ago
  Isn't the universe the only computer in some sense? All of the compute power we have is just an arrangement of matter to have the universe perform computations for us.
  - mjburgess 2y ago
    I don't regard computation as a physical process, or a property of any kind. It's a description of a system, say like "salad" or "party", which whilst informative in conversation, doesn't map to any actual property of reality. ie., there is no property shared by all salads, nor by all computers. Saying, "everything is a computer" is a bit presocratic in its way, like "everything is water" or "everything is fire" In practice, what we mean by "computer" is something which can transmit power in a programmable fashion.. this has more to do with our ability to control devices, and what those devices are, than anything in the "computer". It turns out LCDs, keyboards, CPUs, etc. can all be joined up so I can do something with them.. I call this a "computer" and leave it there. As far as the mathematical definition goes, all functions from ints->ints are computable.. this is eitehr useless or uniformative. It has no relevance for physics.
  - taneq 2y ago
    From that point of view, all the other matter is also a computer, it's just for the most part computing really boring functions.
  - bigboy12 2y ago
    How is it not electric?? You have trillions of fields and particle’s everywhere. How’s it not programmable? It’s computing new structures with gases at any moment.
    - exe34 2y ago
      The electric part seems an arbitrary limitation. The original computers ran off food, which okay technically is chemistry which technically is just a minor application of coulomb's law, but ultimately you can use stones in the desert or water flowing through pipes to compute. Of course all this is still based off chemistry, but you can imagine computing with gravity or nuclear forces.
- figassis 2y ago
  What would happen if you could build an artificial being that was capable of taking in input (action) and provide output (reaction). I don’t think predictability should be a defining property of computers, or we would not be trying to build AI. How components interact with each other, or how it is powered should also not define a computer. Your brain is a computer and we still don’t have much of a clue how it works. We started computing with rudimentary tools and then kept extending that model to what it is today. What would happen if our concepts were entirely different?
  - mjburgess 2y ago
    So you're working backwards from the claim that reality is a computer to defining computer. Yes, by the time you enumerate all the properties of reality, and call them a "computer", you'll find that this is not a computer in the sense of computer science.
    - exe34 2y ago
      That's a bit like determining a ship can only be made of wood, isn't it? A ship needs to float, it needs to be made of buoyant material and it needs to have a sail. If a "sailor" is adjusting the power to a propellor that's turned by an electric motor that's running off a turbine driven by steam from a magical rock, it's not what we define as naval science, is it?
      - goatlover 2y ago
        The thing missing here is that it's only a ship for humans. Ships are cultural artifacts. If we said the universe was a ship that was sailing itself, that would be misapplying something we make for nature itself. Independent of human culture, ships are just arrangements of matter. We make particular arrangements meaningful. Same thing applies to computers and computation. It's only meaningful to use those words for matter we arrange to do certain stuff for us.
        exe34 2y ago
- sesteel 2y ago
  I was taught the universe was a computer in 3 different college courses 25 years ago. Not exactly a revelation. "According to the best physics, the universe: isnt programmable; doesn't evolve deterministically; isnt described by functions over integers; isn't electronic; doesnt transmit power through programmable operation; isn't abstract; doesnt have causal powers through mere arrangements of parts; .. and so on." You can't say any of these things because electronic computers exist within the universe, but I get what your point is. That said, there are physicists beginning to assume the universe IS a computer and work forward from that assumption.
- pasquinelli 2y ago
  before computers were programmable, there were still computers. before they were machines, there were computers. a computer is a thing that carries out a computation. obviously, the universe computes spacetime. but i agree, that's not an interesting fact.
  - constantcrying 2y ago
    If an abacus is a computer, then the term is near meaningless and quite unhelpful.
- random3 2y ago
  perhaps the problem is you're trying to fit computer in the wrong level of abstraction or projecting your position wrt to it incorrectly. E.g. a computer may or may not be programmable for processes that live inside the computer. This said, the compute abstraction is a logical gadget. Logical in the sense that it aims for consistency at a mininmum. A logical gadget is a computer, by Curry-Howard correspondence. This is a broad enough framework to explain why what you're debating against is the case: given that philosophy bridges language to logic and provies the framework for all sciences, seeing nature as compute is like saying there's a logic to nature. So yes, everything is compute. Everything more detailed that that, turing machines, digits, whether it's it from bit or not is a separate matter of debate that may or may not be required.
  - Al0neStar 2y ago
    > everything is compute. Isnt this the problem OP is referring to? If everything is compute then no useful distinction can be made.
    - random3 2y ago
      The utility is relative to the purpose. If everything is compute that you don't know how to program, and that's all you want to do - sure that's useless. If you what you want is a powerful analysis framework, that's gold. If you know how to abstract your way forward with that framework that too. So arguing that the distinction is useless because it's universal, is like saying logic is useless because it's universal.
- croutons 2y ago
  The article clearly states that it’s using our colloquial meaning of “computer” as a metaphor to help convey their thought experiment. It even has a disclaimer about using metaphors. FWIW I think it’s an interesting thought experiment. I think it’s especially interesting to draw the parallel to biology. Clearly our brains are doing computation by even the strictest definition of computer, so at which biological level does computation stop? A chunk of my brain is clearly doing computation, a neuron must be doing computation since that is the building block for our brains. Single cells must also be doing computation since a single cell had all of the computational knowledge encoded in it to build me. All of these processes are built upon physical reality, so it’s not that big a leap that similar processes might emerge elsewhere and at different scales and using different physical mechanisms.
dotsam 2y ago
David Deutsch opposes this view in his 'It from Qubit': https://www.daviddeutsch.org.uk/wp-content/ItFromQubit.pdf https://www.daviddeutsch.org.uk/wp-content/ItFromQubit.pdf > [the view Deutsch opposes] entails giving up on explanation in science. It is in the very nature of computational universality that if we and our world were composed of software, we should have no means of understanding the real physics – the physics underlying the hardware of the Great Simulator itself. Of course, no one can prove that we are not software. Like all conspiracy theories, this one is untestable. But if we are to adopt the methodology of believing such theories, we may as well save ourselves the trouble of all that algebra and all those experiments, and go back to explaining the world in terms of the sex lives of Greek gods. ... > these approaches fail because they attempt to reverse the direction of the explanations that the real connections between physics and computation provide. They seem plausible only because they rely on a common misconception about the status of computation within mathematics. The misconception is that the set of computable functions (or the set of quantum-computational tasks) has some a priori privileged status within mathematics. But it does not. The only thing that privileges that set of operations is that it is instantiated in the computationally universal laws of physics. It is only through our knowledge of physics that we know of the distinction between computable and non-computable (see Deutsch, Ekert and Luppaccini 2000), or between simple and complex. There's a related video here: https://www.youtube.com/watch?v=UohR3OXzXA8 https://www.youtube.com/watch?v=UohR3OXzXA8 And more on what he calls the Mathematicians’ Misconception: https://www.daviddeutsch.org.uk/wp-content/uploads/2018/03/MathematiciansMisconception.pdf https://www.daviddeutsch.org.uk/wp-content/uploads/2018/03/M... Incidentally, Wheeler was his boss at one stage.
- titzer 2y ago
  What Deutsch is saying is that any simulation is going to virtualize all possible observations (including time and any/all side channels), which means there's no way to see through the abstraction. But that doesn't mean we are in a simulation (i.e. are software). It'd be actually kind of dumb if we were, as this universe cannot be simulated efficiently on classical computers--the kind that occur to logicians working from the first principles of mathematics. Our universe wasn't designed by a CS person, that's for sure.
skyyler 2y ago
When the wheel was the hot new technology on the scene, people talked about the universe being a big wheel, too. The universe being a big book was short lived.
stefanha 2y ago
It reads like a patent. Patents enumerate all sorts of possible cases, some of them overlapping, some of them disjoint. Patents do this to claim as much of the idea space as possible, maximizing the reach of the patent. "It's this and it's also that, and that, and that" isn't a great way to communicate an idea. Just explain the idea instead of brain dumping all possible manifestations of it.
- da-bacon 2y ago
  These are notes he typed up, maybe for himself and maybe to share with others. Doing this is a highly effective way to clarify your own thinking. Most of his ideas are listed are mundane, but others, like where he predicts something like quantum computers years before that became apparent are pretty cool to see.
czbond 2y ago
Whoa I've had this same belief - glad to see i wasn't the only person and to see the idea elaborated on.
CuriouslyC 2y ago
The claim "The Universe is a Computer" is a tautology as long as you don't create an overly constrained definition of computer. The claim that is more challenging is "reality is virtual" which basically only implies that space doesn't literally exist.
_akhe 2y ago
People do this thing with computers, intelligence, consciousness... where they attribute it to things that clearly don't have those qualities. If the universe is a computer, I need a new word to describe the tool I'm using - what I normally call "a computer". OTOH, if you call a smartphone a computer, I might have to make some slight modifications to my internal definition, but I can accept that it's technically a computer too - but "the universe"? What are we talking about at this point... Panpsychism puts forth that "consciousness" is in everything. But that abandons what I mean when I say I'm conscious. Maybe a rock is "conscious", but what I mean by consciousness are things like Donald Hoffman's aroma of coffee, the sound of a drop of water, the feeling of being late to a meeting - those kinds of sensations that wouldn't (couldn't) manifest in a rock. LLM chatbot companies are calling it "AI" - abandoning the meaning of what we usually mean by intelligence, which is information awareness, not merely its recitation. Useful conversations nonetheless, but I think different buzzwords could be chosen or even invented to link celestial processes to computational ones - unless there's some agenda, like setting out to prove Simulation Theory or something (which has other problems).
temporarely 2y ago
IF the Universe is a computer, then the important question to ask oneself is "am I a feature or a bug".
- jareklupinski 2y ago
  > "am I a feature or a bug" maybe virus https://www.youtube.com/watch?v=mgS1Lwr8gq8 https://www.youtube.com/watch?v=mgS1Lwr8gq8
telegtron 2y ago
Looking up The Wolfram Physics Project by Steven Wolfram might be of some interest. [0] The Wolfram Physics Project https://www.wolframphysics.org/ https://www.wolframphysics.org/ [1] https://en.wikipedia.org/wiki/Stephen_Wolfram#Wolfram_Physics_Project https://en.wikipedia.org/wiki/Stephen_Wolfram#Wolfram_Physic... [2] Project Launch https://www.youtube.com/watch?v=rbfFt2uNEyQ https://www.youtube.com/watch?v=rbfFt2uNEyQ [3] The Wolfram Physics Project Livestream Archive https://www.youtube.com/watch?v=1K6tfdzM1Jc&list=PLxn-kpJHbPx3NLp4dlriOVAk7GRQ8byVb https://www.youtube.com/watch?v=1K6tfdzM1Jc&list=PLxn-kpJHbP...
quantum_state 2y ago
The statement "The Universe as a Computer" either overly simplifies what the universe is or overly complicates what a computer is ...
lo_zamoyski 2y ago
The statement can only be interesting as a matter of interpretation ("as a computer") of formalism. Formalism, by definition, involves a desemantification of the domain. So yes, if you redescribe some aspect of something in terms of syntactic rules, and then do the same thing for another domain, there might be a correspondence. But correspondence is not the same as identity, especially when the method that produces the corresponding objects involves stripped elements of it away and redefining whatever remains syntactically. Otherwise, a statement like "the universe is a computer" is worthless. "Computation", as understood by computer science, is observer relative. It is a matter of subjective interpretation not objective fact that what we call computing devices are actually computing anything. Computer architecture is a purely abstract mental construct that can at best be simulated using physical devices. "Registers" and "bits" and "instructions" have no objective existence, but we can appropriate matter to simulate the abstract models of these things.
da-bacon 2y ago
Please be gentle on my poor digital ocean droplet :) Note that these notes were not published and were probably something he typed up while thinking about the subject. If you haven’t, I highly recommend checking out one of his “it from bit” papers, they are actually kind of wild https://philpapers.org/archive/WHEIPQ.pdf https://philpapers.org/archive/WHEIPQ.pdf

49 points by dwighttk 2y ago

48(!) possible meanings of the term

In the end, the problem with the claim is that if it is true then 'computer' is defined so loosely as to be uninformative; as soon as you add plausible conditions, it seems obviously false. According to the best physics, the universe: isnt programmable; doesn't evolve deterministically; isnt described by functions over integers; isn't electronic; doesnt transmit power through programmable operation; isn't abstract; doesnt have causal powers through mere arrangements of parts; .. and so on. Whatever it could mean, "computer" here is a strange term. I've no idea why people are so keen on it. I take it to be a sort of humean-idealist-passivist theory: the world is an abstract set of discrete states that are just mere arrangements with no necessary connections; there is only pattern in these discrete states; these patterns are abstract and can be realised by mere number alone. This is roughly somehting like an early 20th C. logicial positivist view, which was somewhat influential -- but it's wholey false, and throw out in scientific practice

optimalsolver 2y ago
>doesn't evolve deterministically Isn't that still debated?
- titzer 2y ago
  Not really. The best models that we have to explain measurable physical phenomenon are wave equations from quantum mechanics that describe probably distributions. There have been proposals for nearly a century that a deterministic model underlies this, but they have to contend with observed phenomenon and inconveniences like Bell's Theorem that suggest that our universe just isn't deterministic. That said, we don't have a unified theory of the universe. General relativity, the dark matter question, and quantum mechanics have not been unified into any mathematical theory. All of those theories are pretty weird, mathematically. And we have no efficient way to simulate on classical computers the models that we do have. We don't live in a billiard ball universe. It's a CS fantasy that evaporates as soon as you start doing experiments on matter and energy in the actual universe we are in.
  - mjburgess 2y ago
    Yes, the biggest problem with this mere mechanistic picture is why anything should move at all. The csci view is essentially a divine command one: the machine runs because of it's 'program' which is somehow external to the machine. But this is a metaphor/illusion for programmable devices like electronic computers, which breaks down for the actual universe. The universe must be inherently dynamical, ie., not mere discrete states that change by rules, but properties whose nature is to interact with the world... This is why the abstract mathematical conception of "computer" cannot describe anything physical: mathematical objects do not have temporal properties; they do not change. This leads to the illusion, for electric devices, that the change is extrinsic to the physics of the system since we can specify the algorithm (somewhat) abstractly. But it isnt.. your pieces of meat, are in the end, the causal power which moves the liquid crystal, electric field, etc.
    - fellowmartian 2y ago
      I think this a caricature or at least a shallow view of computationalism. Nobody is claiming that the universe is a computer of the same kind as the ones we have. Instead, I think, it claims that the universe has to necessarily be computational in order to be real - everything has to be computational to be real, otherwise how can it ever be implemented. On your "divine command" bit: I don't think any theory has a good claim on the ultimate ontology of reality, so I don't see how one view is better than another. It's all some kind of divine command at the moment. Computationalism at least constrains the necessary properties the divine must have.
      - titzer 2y ago
        > everything has to be computational to be real But that's just circular logic. It begs the question as to what is "computational" and what is "mathematical". E.g. Tegmark has good points in the "Mathematical Universe" that describe possible interpretations of what it means to be mathematical. But how is computation different than math? I'd argue that computation is primarily stateful, logical, and (mostly) deterministic with a clear flow of time, whereas mathematical models are often time-reversible (as most, if not of QM is), stateless, and not necessarily "logical" in the sense of relating finite symbolic quantities. Rather mathematical models happily relate infinite series, manifolds, surfaces, high-dimensional spaces, they talk about fields and operate on functions, etc.
madisp 2y ago
Isn't the universe the only computer in some sense? All of the compute power we have is just an arrangement of matter to have the universe perform computations for us.
- mjburgess 2y ago
  I don't regard computation as a physical process, or a property of any kind. It's a description of a system, say like "salad" or "party", which whilst informative in conversation, doesn't map to any actual property of reality. ie., there is no property shared by all salads, nor by all computers. Saying, "everything is a computer" is a bit presocratic in its way, like "everything is water" or "everything is fire" In practice, what we mean by "computer" is something which can transmit power in a programmable fashion.. this has more to do with our ability to control devices, and what those devices are, than anything in the "computer". It turns out LCDs, keyboards, CPUs, etc. can all be joined up so I can do something with them.. I call this a "computer" and leave it there. As far as the mathematical definition goes, all functions from ints->ints are computable.. this is eitehr useless or uniformative. It has no relevance for physics.
- taneq 2y ago
  From that point of view, all the other matter is also a computer, it's just for the most part computing really boring functions.
- bigboy12 2y ago
  How is it not electric?? You have trillions of fields and particle’s everywhere. How’s it not programmable? It’s computing new structures with gases at any moment.
  - exe34 2y ago
    The electric part seems an arbitrary limitation. The original computers ran off food, which okay technically is chemistry which technically is just a minor application of coulomb's law, but ultimately you can use stones in the desert or water flowing through pipes to compute. Of course all this is still based off chemistry, but you can imagine computing with gravity or nuclear forces.
figassis 2y ago
What would happen if you could build an artificial being that was capable of taking in input (action) and provide output (reaction). I don’t think predictability should be a defining property of computers, or we would not be trying to build AI. How components interact with each other, or how it is powered should also not define a computer. Your brain is a computer and we still don’t have much of a clue how it works. We started computing with rudimentary tools and then kept extending that model to what it is today. What would happen if our concepts were entirely different?
- mjburgess 2y ago
  So you're working backwards from the claim that reality is a computer to defining computer. Yes, by the time you enumerate all the properties of reality, and call them a "computer", you'll find that this is not a computer in the sense of computer science.
  - exe34 2y ago
    That's a bit like determining a ship can only be made of wood, isn't it? A ship needs to float, it needs to be made of buoyant material and it needs to have a sail. If a "sailor" is adjusting the power to a propellor that's turned by an electric motor that's running off a turbine driven by steam from a magical rock, it's not what we define as naval science, is it?
    - goatlover 2y ago
      The thing missing here is that it's only a ship for humans. Ships are cultural artifacts. If we said the universe was a ship that was sailing itself, that would be misapplying something we make for nature itself. Independent of human culture, ships are just arrangements of matter. We make particular arrangements meaningful. Same thing applies to computers and computation. It's only meaningful to use those words for matter we arrange to do certain stuff for us.
      - exe34 2y ago
sesteel 2y ago
I was taught the universe was a computer in 3 different college courses 25 years ago. Not exactly a revelation. "According to the best physics, the universe: isnt programmable; doesn't evolve deterministically; isnt described by functions over integers; isn't electronic; doesnt transmit power through programmable operation; isn't abstract; doesnt have causal powers through mere arrangements of parts; .. and so on." You can't say any of these things because electronic computers exist within the universe, but I get what your point is. That said, there are physicists beginning to assume the universe IS a computer and work forward from that assumption.
pasquinelli 2y ago
before computers were programmable, there were still computers. before they were machines, there were computers. a computer is a thing that carries out a computation. obviously, the universe computes spacetime. but i agree, that's not an interesting fact.
- constantcrying 2y ago
  If an abacus is a computer, then the term is near meaningless and quite unhelpful.
random3 2y ago
perhaps the problem is you're trying to fit computer in the wrong level of abstraction or projecting your position wrt to it incorrectly. E.g. a computer may or may not be programmable for processes that live inside the computer. This said, the compute abstraction is a logical gadget. Logical in the sense that it aims for consistency at a mininmum. A logical gadget is a computer, by Curry-Howard correspondence. This is a broad enough framework to explain why what you're debating against is the case: given that philosophy bridges language to logic and provies the framework for all sciences, seeing nature as compute is like saying there's a logic to nature. So yes, everything is compute. Everything more detailed that that, turing machines, digits, whether it's it from bit or not is a separate matter of debate that may or may not be required.
- Al0neStar 2y ago
  > everything is compute. Isnt this the problem OP is referring to? If everything is compute then no useful distinction can be made.
  - random3 2y ago
    The utility is relative to the purpose. If everything is compute that you don't know how to program, and that's all you want to do - sure that's useless. If you what you want is a powerful analysis framework, that's gold. If you know how to abstract your way forward with that framework that too. So arguing that the distinction is useless because it's universal, is like saying logic is useless because it's universal.
croutons 2y ago
The article clearly states that it’s using our colloquial meaning of “computer” as a metaphor to help convey their thought experiment. It even has a disclaimer about using metaphors. FWIW I think it’s an interesting thought experiment. I think it’s especially interesting to draw the parallel to biology. Clearly our brains are doing computation by even the strictest definition of computer, so at which biological level does computation stop? A chunk of my brain is clearly doing computation, a neuron must be doing computation since that is the building block for our brains. Single cells must also be doing computation since a single cell had all of the computational knowledge encoded in it to build me. All of these processes are built upon physical reality, so it’s not that big a leap that similar processes might emerge elsewhere and at different scales and using different physical mechanisms.

dotsam 2y ago

David Deutsch opposes this view in his 'It from Qubit': https://www.daviddeutsch.org.uk/wp-content/ItFromQubit.pdf https://www.daviddeutsch.org.uk/wp-content/ItFromQubit.pdf > [the view Deutsch opposes] entails giving up on explanation in science. It is in the very nature of computational universality that if we and our world were composed of software, we should have no means of understanding the real physics – the physics underlying the hardware of the Great Simulator itself. Of course, no one can prove that we are not software. Like all conspiracy theories, this one is untestable. But if we are to adopt the methodology of believing such theories, we may as well save ourselves the trouble of all that algebra and all those experiments, and go back to explaining the world in terms of the sex lives of Greek gods. ... > these approaches fail because they attempt to reverse the direction of the explanations that the real connections between physics and computation provide. They seem plausible only because they rely on a common misconception about the status of computation within mathematics. The misconception is that the set of computable functions (or the set of quantum-computational tasks) has some a priori privileged status within mathematics. But it does not. The only thing that privileges that set of operations is that it is instantiated in the computationally universal laws of physics. It is only through our knowledge of physics that we know of the distinction between computable and non-computable (see Deutsch, Ekert and Luppaccini 2000), or between simple and complex. There's a related video here: https://www.youtube.com/watch?v=UohR3OXzXA8 https://www.youtube.com/watch?v=UohR3OXzXA8 And more on what he calls the Mathematicians’ Misconception: https://www.daviddeutsch.org.uk/wp-content/uploads/2018/03/MathematiciansMisconception.pdf https://www.daviddeutsch.org.uk/wp-content/uploads/2018/03/M... Incidentally, Wheeler was his boss at one stage.

titzer 2y ago
What Deutsch is saying is that any simulation is going to virtualize all possible observations (including time and any/all side channels), which means there's no way to see through the abstraction. But that doesn't mean we are in a simulation (i.e. are software). It'd be actually kind of dumb if we were, as this universe cannot be simulated efficiently on classical computers--the kind that occur to logicians working from the first principles of mathematics. Our universe wasn't designed by a CS person, that's for sure.

skyyler 2y ago

When the wheel was the hot new technology on the scene, people talked about the universe being a big wheel, too. The universe being a big book was short lived.

stefanha 2y ago

It reads like a patent. Patents enumerate all sorts of possible cases, some of them overlapping, some of them disjoint. Patents do this to claim as much of the idea space as possible, maximizing the reach of the patent. "It's this and it's also that, and that, and that" isn't a great way to communicate an idea. Just explain the idea instead of brain dumping all possible manifestations of it.

da-bacon 2y ago
These are notes he typed up, maybe for himself and maybe to share with others. Doing this is a highly effective way to clarify your own thinking. Most of his ideas are listed are mundane, but others, like where he predicts something like quantum computers years before that became apparent are pretty cool to see.

czbond 2y ago

Whoa I've had this same belief - glad to see i wasn't the only person and to see the idea elaborated on.

CuriouslyC 2y ago

The claim "The Universe is a Computer" is a tautology as long as you don't create an overly constrained definition of computer. The claim that is more challenging is "reality is virtual" which basically only implies that space doesn't literally exist.

_akhe 2y ago

People do this thing with computers, intelligence, consciousness... where they attribute it to things that clearly don't have those qualities. If the universe is a computer, I need a new word to describe the tool I'm using - what I normally call "a computer". OTOH, if you call a smartphone a computer, I might have to make some slight modifications to my internal definition, but I can accept that it's technically a computer too - but "the universe"? What are we talking about at this point... Panpsychism puts forth that "consciousness" is in everything. But that abandons what I mean when I say I'm conscious. Maybe a rock is "conscious", but what I mean by consciousness are things like Donald Hoffman's aroma of coffee, the sound of a drop of water, the feeling of being late to a meeting - those kinds of sensations that wouldn't (couldn't) manifest in a rock. LLM chatbot companies are calling it "AI" - abandoning the meaning of what we usually mean by intelligence, which is information awareness, not merely its recitation. Useful conversations nonetheless, but I think different buzzwords could be chosen or even invented to link celestial processes to computational ones - unless there's some agenda, like setting out to prove Simulation Theory or something (which has other problems).

temporarely 2y ago

IF the Universe is a computer, then the important question to ask oneself is "am I a feature or a bug".

jareklupinski 2y ago
> "am I a feature or a bug" maybe virus https://www.youtube.com/watch?v=mgS1Lwr8gq8 https://www.youtube.com/watch?v=mgS1Lwr8gq8

telegtron 2y ago

Looking up The Wolfram Physics Project by Steven Wolfram might be of some interest. [0] The Wolfram Physics Project https://www.wolframphysics.org/ https://www.wolframphysics.org/ [1] https://en.wikipedia.org/wiki/Stephen_Wolfram#Wolfram_Physics_Project https://en.wikipedia.org/wiki/Stephen_Wolfram#Wolfram_Physic... [2] Project Launch https://www.youtube.com/watch?v=rbfFt2uNEyQ https://www.youtube.com/watch?v=rbfFt2uNEyQ [3] The Wolfram Physics Project Livestream Archive https://www.youtube.com/watch?v=1K6tfdzM1Jc&list=PLxn-kpJHbPx3NLp4dlriOVAk7GRQ8byVb https://www.youtube.com/watch?v=1K6tfdzM1Jc&list=PLxn-kpJHbP...

quantum_state 2y ago

The statement "The Universe as a Computer" either overly simplifies what the universe is or overly complicates what a computer is ...

lo_zamoyski 2y ago

The statement can only be interesting as a matter of interpretation ("as a computer") of formalism. Formalism, by definition, involves a desemantification of the domain. So yes, if you redescribe some aspect of something in terms of syntactic rules, and then do the same thing for another domain, there might be a correspondence. But correspondence is not the same as identity, especially when the method that produces the corresponding objects involves stripped elements of it away and redefining whatever remains syntactically. Otherwise, a statement like "the universe is a computer" is worthless. "Computation", as understood by computer science, is observer relative. It is a matter of subjective interpretation not objective fact that what we call computing devices are actually computing anything. Computer architecture is a purely abstract mental construct that can at best be simulated using physical devices. "Registers" and "bits" and "instructions" have no objective existence, but we can appropriate matter to simulate the abstract models of these things.

da-bacon 2y ago

Please be gentle on my poor digital ocean droplet :) Note that these notes were not published and were probably something he typed up while thinking about the subject. If you haven’t, I highly recommend checking out one of his “it from bit” papers, they are actually kind of wild https://philpapers.org/archive/WHEIPQ.pdf https://philpapers.org/archive/WHEIPQ.pdf