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HTML + CSS3 is Turing complete

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Re: HTML + CSS3 is Turing complete

#31

Post by apgwoz »

mrspeaker wrote: post #16
elitheeli wrote: post #6

Way to steal my karma.... :) As the original author of this, I was going to put it into a much more presentable state before showing it off here. For those confused, here's a proper explanation. No real-world thing can actually be Turing complete (able to express basically any computation that we might want to perform of any size). That's because there are finitely many atoms in the universe, so we can only construct…

That's what happens when you put something on github! In fact, I bet you any money that someone has already taken the code and created a 16-bit logic unit INSIDE minecraft INSIDE your turing machine.

Well, really, it's what happen when you make an impression at Hack and Tell (http://hackandtell.org)! This was perhaps the highlight of last night's Meetup.

Re: HTML + CSS3 is Turing complete

#32

Post by JonnieCache »

elitheeli wrote: post #23
hasenj wrote: post #18

Earlier quoted context omitted.

> No real-world thing can actually be Turing complete But when you say Turing-complete, I assume something along the lines of "a programming language can be built on top of it and you can create interactive applications using such a programming language instead of javascript". It seems like that's not the case at all.

When I say "Turing complete", I mean Turing equivalent to a Turing machine. Since there are infinitely many Turing machines but I'm pretty sure humanity has access to a finite amount of state. I mean it strictly in the theoretical sense.

>I'm pretty sure humanity has access to a finite amount of state

There is at least one man out there who isn't:

http://en.wikipedia.org/wiki/Omega_point_(Tipler)#The_Omega_...

I doubt I'll be drinking that koolaid to be honest.

Re: HTML + CSS3 is Turing complete

#33

Post by kachnuv_ocasek »

elitheeli wrote: post #6

Way to steal my karma.... :) As the original author of this, I was going to put it into a much more presentable state before showing it off here. For those confused, here's a proper explanation. No real-world thing can actually be Turing complete (able to express basically any computation that we might want to perform of any size). That's because there are finitely many atoms in the universe, so we can only construct…

steal karma

Seriously, what the fuck? This is just too much exaggerated.

Re: HTML + CSS3 is Turing complete

#34

Post by bgruber »

elitheeli wrote: post #6

Way to steal my karma.... :) As the original author of this, I was going to put it into a much more presentable state before showing it off here. For those confused, here's a proper explanation. No real-world thing can actually be Turing complete (able to express basically any computation that we might want to perform of any size). That's because there are finitely many atoms in the universe, so we can only construct…

sorry eli, this was just too cool not to share.

Re: HTML + CSS3 is Turing complete

#35

Post by hasenj »

KeithMajhor wrote: post #24
hasenj wrote: post #18

Earlier quoted context omitted.

> No real-world thing can actually be Turing complete But when you say Turing-complete, I assume something along the lines of "a programming language can be built on top of it and you can create interactive applications using such a programming language instead of javascript". It seems like that's not the case at all.

There's plenty of things that are Turing Complete but that shouldn't be used for interactive applications. http://en.wikipedia.org/wiki/Brainfuck http://en.wikipedia.org/wiki/Template_metaprogramming http://en.wikipedia.org/wiki/Turing_machine and now apparently HTML + CSS

Is it not possible to write a C compiler that outputs Brainfuck code that can be executed inside a Brainfuck interpreter?

Re: HTML + CSS3 is Turing complete

#36

Post by JonnieCache »

Tichy wrote: post #29
elitheeli wrote: post #6

Way to steal my karma.... :) As the original author of this, I was going to put it into a much more presentable state before showing it off here. For those confused, here's a proper explanation. No real-world thing can actually be Turing complete (able to express basically any computation that we might want to perform of any size). That's because there are finitely many atoms in the universe, so we can only construct…

I always find the "finite number of atoms" argument a little misleading. Isn't it rather a question of how well we can measure things? If we could measure at infinite precision, one atom would be sufficient to encode all possible states we could dream of. I suppose quantum theory puts a lower limit on the attainable precision of measurements, but I don't know the details. I must admit that since HTML+CSS3 requires cl…

We simply do not have enough information on the nature of reality to decide who is right here.

If space-time does turn out the be physically discrete at the planck length, and the limits of our measurements are actually reflecting the universe's true discontinuous nature, then this would imply that there would be a limit to how much state you could push into an atom.

Any real physicists please feel free to shoot me down in flames here. This is just my (plainly) limited understanding of the situation.

Re: HTML + CSS3 is Turing complete

#37

Post by hasenj »

jules wrote: post #19
hasenj wrote: post #18

Earlier quoted context omitted.

> No real-world thing can actually be Turing complete But when you say Turing-complete, I assume something along the lines of "a programming language can be built on top of it and you can create interactive applications using such a programming language instead of javascript". It seems like that's not the case at all.

Then you assumed a falsehood. Turing completeness is a mathematical concept that has nothing to do with interactive applications.

No, mathematically nothing is "Turing Complete". The only usefulness of saying that something is "Turing Complete" is in knowing that you can treat it as if it was a normal computer for all intents and purposes.

So mathematically a laptop is not Turing Complete, but for all practical purposes, it is.

Re: HTML + CSS3 is Turing complete

#38

Post by jules »

hasenj wrote: post #37
jules wrote: post #19

Earlier quoted context omitted.

Then you assumed a falsehood. Turing completeness is a mathematical concept that has nothing to do with interactive applications.

No, mathematically nothing is "Turing Complete". The only usefulness of saying that something is "Turing Complete" is in knowing that you can treat it as if it was a normal computer for all intents and purposes. So mathematically a laptop is not Turing Complete, but for all practical purposes, it is.

Also incorrect. Counterexample: Turing machines are Turing complete. You are correct that a laptop is not Turing complete, though.

Re: HTML + CSS3 is Turing complete

#39

Post by jerf »

elitheeli wrote: post #26
jerf wrote: post #21

Earlier quoted context omitted.

"eval", followed by whatever chars are required to get a string. I think you mean "the minimum to get a Turing Machine", which is not the same. But I am being pedantic. Very, very pedantic. As befits the topic. :)

But what's in that string? That still counts. What I should have done was put an additional restriction on what IO is available. Otherwise, something like "eval `cat f`" or something could be all powerful. My first attempt shows Ruby simulating a cyclic tag system with only 15 unique characters including newlines and spaces: https://github.com/elitheeli/oddities/raw/master/only_a_few_... EDIT: down to 14 characters.

"But what's in that string? That still counts."

Sure, but it counts regardless of what you're talking about. We don't generally talk about charging data against the TM because they all need data of some sort to do anything interesting. "eval" still gets you there. (Pedantic.)

Re: HTML + CSS3 is Turing complete

#40

Post by riledhel »

nkassis wrote: post #30
mrspeaker wrote: post #16

Earlier quoted context omitted.

That's what happens when you put something on github! In fact, I bet you any money that someone has already taken the code and created a 16-bit logic unit INSIDE minecraft INSIDE your turing machine.

you forgot to mention that the turing machine runs in a browser that runs in another turing machine which is inside a huge machine called the universe.

inside a dream, inside another dream!
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