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Mariposa – A programming language with time-travel

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Re: Mariposa – A programming language with time-travel

#41

Post by rkagerer »

omoikane wrote: post #40

I am confused by the first example: x = 1 t = now() print(x) at t: x = 2 Why doesn't this print `1` before `2`, and then proceed to print `2` in a loop (i.e. treat `at` like a `goto`)? I think there is some detail that separates declaration and definitions of the environment from the execution, but the syntax doesn't make this obvious.

Because the variable was assigned in the timeframe captured by t. It's an example of time travel to the past.

The semantic is confusing at first but think of it like now() took a snapshot of your program and "at t" went back and modified it.

The compiler will evaluate the entirety of your program before execution, and sequence things as directed.

If you're wary this could lead to incomprehensible programs, remember:

It should be understood only as an exploratory game.

Re: Mariposa – A programming language with time-travel

#42

Post by _a_a_a_ »

_Marak_ wrote: post #37

Time loop logic is a hypothetical system of computation that exploits the Novikov self-consistency principle. In this system the computer is able to send the result of a computation backwards through time and rely upon the self-consistency principle to force the sent result to be correct. I've written about this before. Instantaneous data transfer with zero lag is theoretically possible through use of quantum entangl…

https://en.wikipedia.org/wiki/Novikov_self-consistency_princ...

> The principle asserts that if an event exists that would cause a paradox or any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes.

Computer says no.

Re: Mariposa – A programming language with time-travel

#43

Post by xerox13ster »

Terr_ wrote: post #39

That reminds me of a funny presentation which is basically "if we engineered a bunch of exotic sci-fi concepts... what would the perl programs running on them look like?" More formally: "Temporally Quaquaversal Virtual Nanomachine Programming In Multiple Topologically Connected Quantum-Relativistic Parallel Timespaces... Made Easy!" https://www.youtube.com/watch?v=ORjyXcLDd9M

Video Unavailable for me.

Re: Mariposa – A programming language with time-travel

#45

Post by _Marak_ »

Terr_ wrote: post #38
_Marak_ wrote: post #37

Time loop logic is a hypothetical system of computation that exploits the Novikov self-consistency principle. In this system the computer is able to send the result of a computation backwards through time and rely upon the self-consistency principle to force the sent result to be correct. I've written about this before. Instantaneous data transfer with zero lag is theoretically possible through use of quantum entangl…

> Instantaneous data transfer with zero lag is theoretically possible through use of quantum entanglement. No, that's a common myth about quantum stuff. The entangled relationship can't be used to transfer information on its own. Whatever you sample from the "instant parts" can only be checked and understood after additional context arrives in a conventional way--limited by the speed of light and the flow of time. ht…

Ok human. You can read the Hans Moravec paper on CTC and time loop logic to understand Novikov self-consistency principle is formalized, yes you must run the computation for as long as it would have already taken or result will never arrive.

11 years ago I wrote some examples of how password cracking would look like using such setup. https://marak.com/blog/2013-05-13-time-loop-software

I say through "through use of quantum entanglement" as glossy term for reader. Crystalline quantum circuits are not really existing yet so is all scifi.

I won't be able to repsond to further posts in this thread. Cheers.

Re: Mariposa – A programming language with time-travel

#46

Post by jaccarmac »

Terr_ wrote: post #39

That reminds me of a funny presentation which is basically "if we engineered a bunch of exotic sci-fi concepts... what would the perl programs running on them look like?" More formally: "Temporally Quaquaversal Virtual Nanomachine Programming In Multiple Topologically Connected Quantum-Relativistic Parallel Timespaces... Made Easy!" https://www.youtube.com/watch?v=ORjyXcLDd9M

Looks like the YOW site and channel are down, but archived. The video is available at https://web.archive.org/web/2oe_/http://wayback-fakeurl.arch..., which I found via (https://findyoutubevideo.thetechrobo.ca/), also a HN find. Not sure if there is a more ergonomic form for these archived video URLs.

Re: Mariposa – A programming language with time-travel

#47

Post by omoikane »

rkagerer wrote: post #41
omoikane wrote: post #40

I am confused by the first example: x = 1 t = now() print(x) at t: x = 2 Why doesn't this print `1` before `2`, and then proceed to print `2` in a loop (i.e. treat `at` like a `goto`)? I think there is some detail that separates declaration and definitions of the environment from the execution, but the syntax doesn't make this obvious.

Because the variable was assigned in the timeframe captured by t. It's an example of time travel to the past. The semantic is confusing at first but think of it like now() took a snapshot of your program and "at t" went back and modified it. The compiler will evaluate the entirety of your program before execution, and sequence things as directed. If you're wary this could lead to incomprehensible programs, remember:…

Got it, looks like all the `at` need to be evaluated first.

I think Mariposa should be added to esolangs.org

Re: Mariposa – A programming language with time-travel

#48

Post by eigenket »

_Marak_ wrote: post #37

Time loop logic is a hypothetical system of computation that exploits the Novikov self-consistency principle. In this system the computer is able to send the result of a computation backwards through time and rely upon the self-consistency principle to force the sent result to be correct. I've written about this before. Instantaneous data transfer with zero lag is theoretically possible through use of quantum entangl…

> I've written about this before. Instantaneous data transfer with zero lag is theoretically possible through use of quantum entanglement.

I hope you wrote a correction wherever you wrote this. Quantum entanglement can not transfer information by itself (because of the no-communication theorem) therefore any data transfer protocol that uses entanglement must also use some other form of communication (e.g. classical communication), and therefore is at most as fast as your other communication method is.

Re: Mariposa – A programming language with time-travel

#50

Post by rkagerer »

_Marak_ wrote: post #45
Terr_ wrote: post #38

Earlier quoted context omitted.

> Instantaneous data transfer with zero lag is theoretically possible through use of quantum entanglement. No, that's a common myth about quantum stuff. The entangled relationship can't be used to transfer information on its own. Whatever you sample from the "instant parts" can only be checked and understood after additional context arrives in a conventional way--limited by the speed of light and the flow of time. ht…

Ok human. You can read the Hans Moravec paper on CTC and time loop logic to understand Novikov self-consistency principle is formalized, yes you must run the computation for as long as it would have already taken or result will never arrive. 11 years ago I wrote some examples of how password cracking would look like using such setup. https://marak.com/blog/2013-05-13-time-loop-software I say through "through use of q…

The salient bit from _Marak_'s article:

Time-loop logic does not violate causality. We are able to retrieve the answer instantly because we have committed to spending sixty seconds in the future calculating the answer and sending it back.

Maybe quantum superposition is just the universe compiling.

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