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Computation as a universal and fundamental concept

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Re: Computation as a universal and fundamental concept

#121

Post by Robotbeat »

jibal wrote: post #85
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…

> 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

Re: Computation as a universal and fundamental concept

#122

Post by Robotbeat »

chermi wrote: post #63
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…

Did you mean landauer?

Yes. Unable to edit it. https://en.wikipedia.org/wiki/Landauer's_principle

Re: Computation as a universal and fundamental concept

#123

Post by peter_m1 »

kaashif wrote: post #57

I like how every time a new technology is invented and becomes big, people start to think it explains everything. Like how in the 16th/17th centuries some people thought the universe was a big clock. Or how in the 19th centuries people thought the universe was like a big steam engine. Or now we think the universe is a big computer. Not saying this is wrong or that I've watched all of the lectures above or anything, b…

Yes, these are all our attempts at explaining the nature of reality. A kind of reaching into the unknown. A desire to understand the universe and our place in it.

Re: Computation as a universal and fundamental concept

#124

Post by peter_m1 »

sdevonoes wrote: post #46

From my naive pov: Related to computation is the concept of state (I know, functional languages can get away without it, sort of). I always wondered how the universe “knows” the mass of the sun. If there are some underlying functions/computations “running” in the background to keep planets moving and so on, and if the mass of planets is a key element in such computations… then either: the mass is calculated “on the f…

The theory of general relativity answers this exact question. It has been tested experimentally and has been found to be correct in the classical regime. By correct I mean that the experimental data agrees with theoretical prediction.

Re: Computation as a universal and fundamental concept

#126

Post by peter_m1 »

jeffrallen wrote: post #33

Discrete math and Algorithms were two of my favorite college classes. They were really the only part of computer science that was mind blowing. The rest was software engineering, which was transparently "possible". Like, yes, big programs and OSs and numerical models exist, and yes I will graduate and work with them and add to them, someday, yeah sure. But decidabilty, Godel's theorm, busy beaver numbers, etc... thos…

Theoretical computer science is where it's at.

Re: Computation as a universal and fundamental concept

#127

Post by peter_m1 »

voidhorse wrote: post #100

Computation as realized by computers is a formalism invented by Turing, Church, Kleene and others to make precise the intuitive notion of "algorithm". An algorithm, at its root, is a procedure rooted in human understanding that human beings can follow. When Turing and others first introduced this formal notion, not all mathematicians were even fully convinced it was an adequate representation of the informal intuitiv…

The computational view of the universe and the nature of reality has provided us with some new insights.

Re: Computation as a universal and fundamental concept

#130

Post by andsoitis »

dchftcs wrote: post #88
Diogenesian wrote: post #65

Earlier quoted context omitted.

Information and computation are not the same thing. I was very specifically talking about Turing machines and other theoretical models of computation. That said, you are still making the same mistake I pointed out, elevating human symbolic information to a higher plateau than it deserves. I think it's because you're being too vague about the connection, when it's fairly mundane. The "fundamental connection" is that p…

A more concise explanation is that, computation is the transformation of information. Any transformation of information is computation, and is thus subject to some theory of computation. A physical process involves the transformation of information, so can be studied with a theory of computation.

> A physical process involves the transformation of information, so can be studied with a theory of computation.

A rock rolling downhill has state-dependent future behavior you could describe informationally, but nothing is gained by modeling it with automata theory instead of Newtonian mechanics, and it isn't computing in any substantive sense.

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