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Life in life

Phillip Bradbury · Youtube · 373 HN points · 37 HN comments
HN Theater has aggregated all Hacker News stories and comments that mention Phillip Bradbury's video "Life in life".
Youtube Summary
A video of Conway's Game of Life, emulated in Conway's Game of Life.

The Life pattern is the OTCA Metapixel: http://www.conwaylife.com/wiki/OTCA_metapixel - for more information, see http://otcametapixel.blogspot.com.au/

The life simulator used is Golly - http://golly.sourceforge.net/ which has a built-in script to generate these metapixel grids (select a pattern, and choose "metafier.py" from the scripts list).

Inspired by this video: http://www.youtube.com/watch?v=QtJ77qsLrpw but with the speed and scale varying smoothly over time, rather than in discrete jumps as the original video did.

The actual video is exported from Golly using a custom Python script: https://github.com/mrphlip/life3/tree/main/life2 (since Golly built-in only supports rendering the view with a scale which is a power of 2, for performance reasons - this is not a particularly well-optimised or fast script to run).

The audio track used to be a Shepard Tone, but that was horrible, so I replaced it with some of the music in YouTube's library (Jingle Punks - Back of the Room Hang)... if you really want to hear the original version, it is over here: https://www.youtube.com/watch?v=zOwFvytK5K0
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Hacker News Stories and Comments

All the comments and stories posted to Hacker News that reference this video.
I wonder if you could bypass this with a level of indirection.

If the GoL wizards can construct an expanding and initially configurable 'GoL in GoL' grid [1], they could configure the 'garden of eden' as the initial configuration for their 'GoL in GoL' simulation.

It's not the same thing, of course, but it would allow you to run Garden of Eden patterns still starting with just your initial 15 gliders.

To construct a garden of eden pattern, you must first construct the universe :)

[1] similar to https://www.youtube.com/watch?v=xP5-iIeKXE8

chriswarbo
Sure, we can build them with "meta cells"; but that's just emulation (the same way a SNES emulator doesn't make my laptop a SNES).

We already have GoL turing machines (with "tape factories" that travel faster than the read/write head); we could likewise use those to emulate GoL with arbitrary input, just by setting up an appropriate "tape". The result is far less pretty though ;)

I touched on this in a sibling comment: https://news.ycombinator.com/item?id=33799084

Reminds me of Conway’s Game of Life, emulated inside Conway’s Game of Life:

https://m.youtube.com/watch?v=xP5-iIeKXE8

FWIW: https://www.youtube.com/watch?v=xP5-iIeKXE8 If you allowed toggling particular points manually as input from a controller... probably not too far away from possible!
I think the author is misunderstanding the XKCD comic about rocks [1] (or maybe I am). Just because it's possible to run a simulation of the universe on rocks, doesn't mean that rocks are conscious or turing complete. You can't forget about the person who is manipulating the rocks. The system as a whole is turing complete. Likewise with the bar of iron example that the author gave, you can't forget about the person interpreting the atoms in the bar of iron. The system as a whole is turing complete (and also naturally conscious, because the person doing the interpretation is conscious).

And there is nothing physical necessary to represent such systems. You can simulate turing complete systems inside turing complete systems [2]. So I don't see why consciousness has to be a "physical phenomenon" as the author claims.

[1]: https://xkcd.com/505/

[2]: https://youtu.be/xP5-iIeKXE8

Mar 18, 2022 · 2 points, 0 comments · submitted by st_goliath
Feb 05, 2022 · caf on Accidentally Turing-Complete
One thing it doesn't mention is Conway's Game of Life itself.

So of course, you can implement Game of Life within Game of Life:

https://www.youtube.com/watch?v=xP5-iIeKXE8

pfdietz
This book on the engineering of mechanisms in Life is absolutely insane.

https://conwaylife.com/book/

fjfaase
Maybe it was not included, because John Conway suspected that it would be Turing complete from the start. Because he suspected this he contacted Martin Gardner and asked the public for searching for an ever growing pattern, resulting in the discovery of the glider gun. He realized that finding something like a glider gun would be the first step in establishing Turing Completeness. It took some time for it to be proven completely, but from the start the intuition of Conway was that Game of Life would probably be Turing Complete.
This video doesn’t go into any detail, but is perhaps the best illustration of the concept.

https://youtu.be/xP5-iIeKXE8

Edit: yes I am late to the party.

Yup

https://youtube.com/watch?v=xP5-iIeKXE8

lambic
It's cellular automata all the way down.
I missed that, thanks! I'll have to take another look.

When I think of neural networks that evolve changes in their topology and the weights between those connections, over and over towards optimizing a solution to function, I get the vision of the recursive Life in Life video[1] where Conway's Game of Life is emulated in Game of Life.

[1] https://www.youtube.com/watch?v=xP5-iIeKXE8

Unknowable.

And no, you'll have no way to break out of simulation and access api of the simulator, because if it's in place it works similarly to this:

https://m.youtube.com/watch?v=xP5-iIeKXE8

fabiospampinato
Not necessarily, there might be bugs in it.
scotty79
Sure, because gods that made math are known to be crappy developers. ;-)
fabiospampinato
You don't need to be crappy to make something that isn't perfect, maybe it's not even possible to prove that something extremely complicated like the universe is bug-free.

Obviously though it might be a matter of perspective, we might as well be gods compared to ants, our code might be buggy but I don't think ants are smart enough to figure that out.

scotty79
Complexity of the universe comes from super simple (relatively for gods) rules of math.

You don't have bugs in math.

fabiospampinato
There's actually a math theorem that says basically that, unless I'm misunderstanding, if your math has no bugs you can't prove it has no bugs with it.
scotty79
Not quite. It just says that if you assume set of axioms and math grammar you may generate statements that are not false but you can't constructa a proof with what you allowed yourself. I don't think it's a bug.
fabiospampinato
I think that's another theorem.
scotty79
Dunno, I thought you were refering to Godel's theorem.
fabiospampinato
Yes I think you were referring to the first incompleteness theorem while I was referring to the second one: https://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_...

> The second incompleteness theorem, an extension of the first, shows that the system cannot demonstrate its own consistency.

scotty79
This one just says that any non-trivial consistent set of math doesn't contain the proof of its consistency. Where consistency means it doesn't contain proofs of falsehoods.

It doesn't seem like a bug to me. Just a way to ensure that any non-trivial math has no self sufficient bubbles. That no set of math is somehow better than others. That math is free and unlimited with it's choice of axioms and rules and no subset is better than others.

fabiospampinato
I wouldn't consider it a bug either, I didn't mention it because I thought it was a bug, I mentioned it following this line of thought: "You don't have bugs in math." -> if math were inconsistent it would be buggy -> if math is inconsistent it's buggy -> if it's not inconsistent you can't prove that it's not inconsistent -> you can't tell whether math has bugs in it (unless you can find some), which is a contradiction from your statement that there are just no bugs. It's basically impossible to prove that, and if you can't prove something you are left with nothing more than doubt.
scotty79
Ah I see. But it's only the case if you limit yourself to a subset of math. Subset of math is not provably consistent if you are trying to use just itself for the proof, but this subset is provably consistent if you extend your proving toolset with something else.

But the new extended subset has new, other troubles that make it impossible to prove its consistency by using just itself, so to prove its consistency you need to extend it again.

You can still have fully provable (i.e. bugless) subset of math, you just need other math to prove that it is so.

fabiospampinato
Other math that you can't prove it's consistent, you end up just moving the problem one step away, but it's not going away.
scotty79
Yes. But you don't need the whole math to run the universe. Just a subset of your choosing. And you can go beyond that subset (to a wider god-math) to prove that this subset is consistent.

And the fact that your extended god-math can't prove that it is itself fully consistent (doesn't generate any proofs of falsehoods) is not necessarily a problem. It's enough if no falsehoods were involved in the proof of the universe-math consistency.

And that's entirely possible. Theorem you mentioned doesn't say anything about that.

krustyburger
Well, we know there are bugs in this reality. I believe the relevant field of study is called entomology.
Right, obviously as scale goes up, much more complexity is needed to maintain the same level of behavior. A bit like how unicellular organisms can replicate simply, but humans need to go through a whole process to make an offspring.

This Game of Life video shows what I mean perfectly: https://www.youtube.com/watch?v=xP5-iIeKXE8

Yes, there's a ton of complexity in there, but when you zoom out enough, it looks and acts very similar to the lower level.

fooker
Wow this is awesome! Thanks.
amelius
Very nice, but of course this was designed/engineered to act like this. It's basically a computer implemented in the game of life, which runs the game of life.
Conway's Life in Conway's Life:

https://youtu.be/xP5-iIeKXE8

ineedasername
Wow, if that can be done, I don't see any theoretical reason why it couldn't keep going n-levels deep.
robotresearcher
That's right. And because Conway's Life is known to be Turing Complete, it can implement any other Turing Complete machine. So you can stack up as many computers as you want, in any sequence.

'Can' here means in theory you can. That doesn't mean that finding the state you need to implement the next level machine will be easy. Life on Life is impressive. I got shivers when I first saw it.

They are a novelty that is often surprising in the how their simple set of rules can lead to quite amazing emergent complexity. That the one-time chaotic game of life was eventually shown to be able to stably infinitely expand and be turing complete is quite interesting.

I don't know that they'll ever be useful for efficient computation, but they will likely always remain fun.

https://www.youtube.com/watch?v=xP5-iIeKXE8

I have not read it myself, but I know that Stephen Wolfram ( of Mathematica/Wolfram Alpha) laid out some arguments for the usefulness of studying cellular automata in his early 2000s book "A New Kind of Science".

My secret wish is that they start working on Factorio 2 with a new item state-memoizing game engine. Let me explain.

Conway's game of life organisms' different states can be memoized. Starting the simulation slowly, an engine can memoize the following computations. This is what Hashlife [1] does. Quoting from Wikipedia: "the rapid increase in speed is often described as "exploding"."

So much so that this kind of thing is possible: https://www.youtube.com/watch?v=xP5-iIeKXE8

Simulating the next ticks just entail looking up the future. Except for things the users touch.

Since Factorio is a game about reaching the next scale of automation, I believe this is a worthy follow-up to Factorio 1.

[1] https://en.wikipedia.org/wiki/Hashlife

dexwiz
That sounds interesting, but what is the game here? Fractal factories where you build the internals, it memoizes a series of states, and then you can use that as a black box when building the layer above? Actually that does sound pretty cool.
BenoitP
Oh, I forgot to mention that megabases currently are CPU limited. A truly new kind of megabase would be enabled by it.
dexwiz
SpaceChem had a similar version of this. You started by building individual factories and later puzzles had you assembling multiple factories together. You could choose to try to cram several steps into few, complex factories, or spread out simple steps over many factories.

I think SpaceChem is similar to Factorio, in that there is no single solution. The designer of SpaceChem said he just tried to create interesting problems, but didn't spend too much time going through possible solutions. Factorio is similar, in that there are set recipes, but how you move from one to another is completely up to you.

I remember seeing that video 3 years ago and being blown away.

In case someone doesn't already know it, here is Conway's Game of Life simulated in Conway's Game of Life:

https://www.youtube.com/watch?v=xP5-iIeKXE8

selestify
Blog post about the OTCA metapixel: https://web.archive.org/web/20200831001939/http://www.amanda...

Previous discussion: https://news.ycombinator.com/item?id=24323011

I find this initially unintuitive, but it makes sense when you think about it.

Look at any other system that produces aggregate emergent behavior out the behavior of smaller parts. For example, here's Conway's Game of Life implemented using... Conway's Game of Life: https://www.youtube.com/watch?v=xP5-iIeKXE8 It takes many many steps of the inner game of life to produce a single iteration of the outer simulation.

In general, with emergent behavior, it takes a lot of inner steps to produce a single meaningful step in the outer system. So it makes sense that our cells are much faster than we intuititively think of as "fast". Because our intuition about speed is itself the product an emergent system. We are that larger Game of Life there, so it looks incredibly fast to watch the inner one according to our own time scale.

gotostatement
what's interesting is that the GoL inception is (as far as I understand) highly sensitive to initial conditions and timing in order for everything to sync up properly, whereas the cell is really robust in terms of everything just jumping around randomly and yet still getting its tasks done
elcritch
One big difference is the dimensionality, of 2d vs 3d. Even within the 3d space, quantum chemistry effects produce an even higher order of "effective" dimensionality. Finding stable paths that don't interact in 2d is hard, but easier in 3d. Its even easier in hyper dimensional spaces where other chemical properties can be used to provide pathways for only specific reactions.
Pulcinella
Yeah it feels as if the cell is a ridiculously parallel array of molecules where every molecule in the array is rapidly iterating through the array (colliding with every molecule in the cell as it diffuses) and type checking those items to see if it can operate on them (e.g. a protein breaking down a small molecule). It all works out because the operations are atomic (heh) (don’t need to worry about two proteins trying to break down the same molecule at the same time) and the type safety (proteins are highly specific on what kind of chemicals they target) means you don’t need to worry about trying to perform some invalid operation.

Turns out collision detection is real fast in real life!

kneel
Another analogy: molecule interactions are like proof of work operations that unlock cell actions when the right fit (hash) is found. trillions of molecule interactions are required to find the right fit.

the intricate network of transcription factors operate as a security system to unlock key processes in DNA regulation in eukaryotes. security must be maintain because the system is under constant attack from other information systems (viruses)

candiodari
The thing that is ignored here is that while molecules move fast ... they go nowhere. It's a random walk. It takes 6 hours for your small protein molecule to move 1cm ... at 250kph.

So while these molecules offering themselves up "automatically" works, it only works at very short ranges and it's a stochastic range. At 1nm they meet 100k times per second. At 1cm once per 6 hours. At 3cm once per month.

So there is in fact a lot of bookkeeping, keeping things tethered where they need to be and dragging things around to be done inside the cell where everything magically happens. People in this thread aren't correct that it's not necessary to do that. You don't need to get positions exactly right, as in you don't have to get the amino acids in every ribosome, but you DO have to get them "more or less" where they need to be. If for example if the amino acid concentrations near ribosomes ever get low, that's the end of you in about 2h (there's a fungus that causes that).

gotostatement
interesting. so the idea that this all happens just because every molecule interacts with every molecule many times per second, as advanced in the blog post, is not correct?
xwdv
What would happen if a cell were somehow to be optimized such that every operation occurs in O(1) time rather than having to iterate?
nsxwolf
This is probably what happened to Tetsuo in Akira.
pas
Hm, well, it would require a "global" approach instead of what currently happens. Which is the opposite, local gradients, local diffusion, local parallel approaches. Many times things are being built, remodeled, moved, teared down, packed for moving, and unpacked for use. Everything is at the same time a tool for building bigger things and is just a piece of raw material if something else happens to disassemble it or use it for assembling something bigger.

So opposed to that there would need to be some kind of ordering, signaling, queuing, synchronization, etc.

Thanks to osmosis building block things are always pretty close when they are needed, and products are always getting spread out evenly too. (And there is a transport network in each cell that helps with those that need some help spreading.)

Of course there are certain things that work based on a kind of synchronization, like the waiting for all actin fibers and the two copies of each chromosome during cell division (probably the metaphase) to be in place so they can start pulling apart the cell nucleus (anaphase), and then the daughter cells can separate. Of course this also depends on signals (cyclins). The G1 cyclin slowly accumulates, and unless it's inhibited (by eg. signals get produced when "lack of nutrients" state happens around the cell) it'll start a cascade to ultimately split the cell in two.

Similarly there are certain genes that are environmental gradient dependent, usually these work when a stem cell differentiates into something specific. And the stem cell stuff is active because some parts of the DNA is conveniently exposed, certain signaling pathways are active - so the cell reacts to the gradient. And after differentiation those things get put away, locked down, coiled up, broken down, absorbed, etc.

Okay, so how could a cell skip all those iterations? It needs to know what to do and when, that's environment dependent (locally signaled by other cells, and sometimes signals arrive from far via special stuff in the blood, eg. hormones). Something like that could be probably implemented in cells. Eg. "simply" enumerating all the functions of a cell and making every process inside it depend on outer signals, and maybe leave the simple accumulators.

And when any process is about to start the cell would need to know if it has enough resources to go through with it. This would basically need yet another signaling and computational system. Or, sure, it might just start things and ... fail to finish it in time, but then it needs to disassemble whatever is half-finished. And basically that's already what happens. All the time. And if something is "really needed" it'll be finished fast. (Because signals inhibit things that slow things down, and also maybe slow down the cleanup crew too.)

shuntress
Cancer, probably.
foobarian
So it's kind of like React hooks, except they are probabilistic and constrained by 3d geometry. And the things moving around fast inside the cell is the event loop. Fun!
thaumasiotes
> the type safety (proteins are highly specific on what kind of chemicals they target) means you don’t need to worry about trying to perform some invalid operation.

You might want to look into the mechanics of heavy metal poisoning.

There is no type safety, and there's no type checking. Everything attempts to interact with everything it encounters. Those interactions usually fail.

2017 post has a much-needed youtube video of the metapixels as the top comment: https://www.youtube.com/watch?v=xP5-iIeKXE8

I haven't been able to find one for tetris tho

Apr 12, 2020 · 68 points, 5 comments · submitted by ZhuanXia
_5659
The way I understand why this is possible is due to the fact that Game of Life is Turing Complete, and can therefore construct a Universal Turing Machine capable of simulating itself.
3pt14159
Well, kinda. This is an intentionally visual representation, but it could just have been a rules set that builds a series of gates that create a computer that does the calculations for the game without actually rendering it. Basically seeing the game isn't necessary, though this is pretty awesome.
BenoitP
Lots of interesting software around Conway's Game of Life. Here is Hashlife [1], where the states of living organisms are hashed; sometimes enabling prediction of all future states.

It helps trading-off computation with space, sort of like Halide [2] does.

I've been playing a bit of Factorio with the social distancing recently. The bottleneck of mega-bases is often compute power. I wish the developers could implement something akin to Hashlife. The bases are made of the same repeated patterns, all possible states of which could be memoized. This could be the next step in automating to a higher scale.

[1] https://en.wikipedia.org/wiki/Hashlife

[2] https://halide-lang.org/

klyrs
Factorio has some real challenges to it -- ticks are extremely fine, and for example, the speed of an inserter is dependent on availability of electricity. Combine such aspects with, say, the plurality of materials which may be on a belt. I fear that the plurality of possible states would move the problem from being compute-bound to being memory-bound.
BenoitP
Yep, such details would eat memory at a fast pace. However, non 100% electricity and non backed up belts could be considered an "off the main path", and be resolved computationally; sort of like the Java JIT deoptimizing an edge case and going back to the interpreter mode.

Players would then strive to make stable, robust bases with as few states as they can. Failing to do so would mean the slow path, and their factory struggling to progress in IRL time.

The optimizing limit doesn't have to be a hard-coded threshold, it could be defined as a cache with a limited capacity.

Apr 11, 2020 · 227 points, 31 comments · submitted by eigenvalue
lainwashere
Every time I watch this video, I get a sense of existential crisis. Another cool video that relaxes me is this one [0]. It feeds another type of Turing complete cellular automaton called Rule 110 [1] into Game of Life.

[0] https://youtu.be/P2uhhAXd7PI

[1] https://en.wikipedia.org/wiki/Rule_110

eigenvalue
That’s really creative to combine the two CAs like that, I’ve never seen that done before. It suggests a whole algebra of the objects that result from composing two systems.
dangirsh
This simulation is used in an analysis of self-referential dynamics: https://arxiv.org/pdf/1711.02456

I recently posted other impressive Life patterns here: https://news.ycombinator.com/item?id=22851258

JadeNB
Reminder: please always post arXiv links to the abstract page, not directly to the PDF. https://arxiv.org/abs/1711.02456
hanoz
Mind blowing as this is, I feel the video would be much improved if it gave some visibility to the birth/death transition in the second order cells while still zoomed in enough to see a bit more of the workings of the first order elements.
stallmanite
Are there any visualizations that you can recommend that capture what you describe?
sandworm101
Must see evolution of GOL: "SmoothLife is a family of rules created by Stephan Rafler. It was designed as a continuous version of Conway's Game of Life - using floating point values instead of integers."

https://www.youtube.com/watch?v=KJe9H6qS82I https://www.youtube.com/watch?v=qaB-uHfScjU

failrate
I show this video to all incoming software engineering interns.

It's partially educational and partly just very amusing watching their brains leak out of their ears.

squarefoot
This one was among the suggested videos. I could only dream of a game engine based on that.

https://www.youtube.com/watch?v=kEB11PQ9Eo8

failrate
That's very cool. Thanks for sharing. Manifold Garden and Antichamber non Euclidean 3D games. Antichamber is quite good.
saagarjha
The subtitles for the video are great. Somewhat related, the OTCA Metapixel was also used to implement Tetris (well, an entire RISC computer and high-level language, really) in Life: https://codegolf.stackexchange.com/questions/11880/build-a-w...
segfaultbuserr
Has this submission ever reached the HN homepage? I personally tried to submit it twice but no upvotes at all, which I believe it deserves. I just checked the history again [0], none of the post ever made it, which is unfortunate. I thought Hacker News readers would be interested in a RISC processor built in the Game of Life.

[0] https://hn.algolia.com/?q=https%3A%2F%2Fcodegolf.stackexchan...

saagarjha
Sadly, Hacker News can be quite fickle…
xwdv
Getting upvotes to get on the front page is fairly political sadly.
segfaultbuserr
I won't say it's political, and it isn't about karma. There are political submissions (I sometimes submit/upvote political articles deliberately to "test the water", i.e. not because I agree, I simply want to see what are the opinions here), and there are cases when people care about karma.

But often, there are simply many technically interesting articles you'd want to share, and I have a small history of success of submitting technically interesting articles to the homepage with no politics involved, such as tips and tricks of microcontrollers or the use of 50-ohm transmission line in RF engineering. My conclusion is that an attractive title [0] and some luck is needed. However, I tried to include the keyword "Building a RISC processor in Game of Life", but it still fails to get any votes.

My conclusion is, unfortunately, the majority of HN reader doesn't know what the Game of Life is and/or doesn't think building things in GoF is attractive.

[0] HN has a fairly strict "original title" rule to discourage clickbait, I mostly agree, but sometimes a title genuinely doesn't completely explain and provide enough context about what is in the article, which is otherwise interesting. No votes and no readers would be the result, which isn't really fair.

Arcorann
https://news.ycombinator.com/item?id=15246348

First hit when searching for Tetris.

segfaultbuserr
Thanks for the link. It turns out to be better than I expected!
pankajdoharey
GOL can be made into a turing machine so this shouldnt come as a surprise https://www.ics.uci.edu/~welling/teaching/271fall09/Turing-M...
jaimehrubiks
John Conway, inventor of the game of life, just passed out because of coronavirus. :(
dreamcompiler
What blows my mind about this is not the universal computation simulating itself, but that it looks a lot like ribosomes decoding RNA and making protein. And then flashing that it doesn't just look like them.
bmmayer1
Serious question, how did they discover this? AFAIK GoL patterns can't be reverse engineered.
new2628
You can think about it step-by-step: first you need some rectangular structure that has two well-defined states to represent your cells, then you think of how to implement periodic refresh and communication between neighboring cells, some gadgets for and/or gates, etc. As you have gliders, glider guns, and similar building blocks, it is not that difficult, given enough patience. Very nice to look at though :)
__s
For more insight on designing GoL circuits: https://codegolf.stackexchange.com/a/111932

The hardware metaphor seems apt, as GoL has a speed of light & the parts operate concurrently

So not sure what you mean by reverse engineered, maybe you're getting hung up on Kolmogorov complexity being incomputable

LeoPanthera
Life is turing complete, so there was no need to “reverse engineer it”, they built a computer that is simply simulating life, in life.
vecter
Based on following the links in the video details, it looks like it's built around something called the OCTA metapixel [0][1][2].

Conceptually, I could see how once you have an "abstract programmable pixel" with mechanisms to change how they interact with each other, it becomes "straightforward", since you can abstract away the concept of a pixel and its interaction with neighbors.

[0] https://www.conwaylife.com/wiki/OTCA_metapixel

[1] https://otcametapixel.blogspot.com/2006/05/how-does-it-work....

[2] https://b3s23life.blogspot.com/2006_09_01_archive.html

HABytes
How did they recover this...?
saagarjha
You might find some of the details of its construction interesting: https://www.conwaylife.com/wiki/OTCA_metapixel#Details. While it doesn't explain the inspiration behind it, it does show that there's a definite structure to it.
a_t48
This one is also pretty fascinating - https://www.conwaylife.com/wiki/Deep_cell
sudoaza
And the looped version https://coub.com/view/25kpyt
voz_
This is amazing
airstrike
Color me awed.
You can not only build a turning machine with GoL, but you can build GoL in GoL

https://youtu.be/xP5-iIeKXE8

Neat! In a similar vein, here's Game of Life implemented in Game of Life:

https://www.youtube.com/watch?v=xP5-iIeKXE8

dmos62
Now I've seen everything.
JKCalhoun
I wonder if there is a smaller (in terms of cell size) way to implement this.
andyjohnson0
According to Wikipedia, a cellular automaton running the game of life rules is Turing complete. So it can compute anything that a Universal Turing Machine can compute [1] - In other words, anything that a conventional computer can compute.

[1] https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life

wizzwizz4
Including Tetris. https://codegolf.stackexchange.com/q/11880/43394
Mar 12, 2020 · 1 points, 0 comments · submitted by rrauenza
Dec 01, 2019 · 2 points, 0 comments · submitted by 0xBABAD00C
You mean something like this?

If you don't want to be "spoiled" as to what exactly the video is going to show as it zooms out, use this link.. and don't pay attention to the browser tab title, or the video title in the top left corner, until it disappears in about 3 seconds along with the rest of the UI:

https://www.youtube.com/embed/xP5-iIeKXE8?autoplay=1 [1:29]

Canonical link:

https://www.youtube.com/watch?v=xP5-iIeKXE8 [1:29]

uranium
Whoa--I'd heard of that computation, but I thought the resulting output was single-cell, not big obvious blocks like that. That's beautiful.
baddox
Yep, the OTCA metacell was exactly what I was thinking of. We know that the game of life is Turing complete, so the only challenge is figuring out how to make the graphics look presentable when zoomed out. Someone must have just implemented a 2d graphics environment on top of game of life.
Molecular biology: https://youtu.be/_SGoDIkscXg?t=39

Game of Life: https://youtu.be/xP5-iIeKXE8

Sure, one is 2D and discrete, the other is 3D and continuous... oh wait, Lenia is 2D and continuous. That’s interesting.

nivertech

    2D and discrete   -> Conway's Game of Life
    2D and continuous -> Lenia
    3D and discrete   -> Minecraft ?
    3D and continuous -> Molecular biology
tree_of_item
Sure, being continuous is cool, but your parent is absolutely right that calling anything about this "biology" is way out of line.
veddox
My comment had nothing to do with the number of dimensions or whether the world is continuous or discrete. (AVIDA and many other biological models are both 2D and discrete.)

The two core characteristics of life are metabolism and reproduction. Metabolism requires some kind of input, a resource, that is somehow consumed or transformed as the organism grows or is active. Reproduction places an organism in a long line of descent, possibly with mutation and evolution, akin to what we like to call Life.

Sure, living organisms show (symmetrical) organisation - but that is because this morphological organisation enables metabolic functions and reproductions. The morphology does not arise because of some random mathematical rules, but because it fulfills a specific need. It is not an end in itself. This teleological perspective is completely lacking in cellular automata such as Lenia.

(edited for clarity)

Here's a nice video showing OTCA metapixels in action, implementing Game of Life in Game of Life.

https://www.youtube.com/watch?v=xP5-iIeKXE8

It would be amazing to see this Tetris computer rendered into a video like this.

ImaCake
If you read down the stackoverflow page long enough there is a link to a runable version of the code.

http://play.starmaninnovations.com/qftasm/#jllHdnBGSP

isoprophlex
This would need to be compiled into a pattern for the intermediate automaton, which is then run on the metapixel layer in GOL? I think?

Anyway this is the coolest thing I've read all year, and I'm not kidding

avian
True, but the runnable code on that page is several levels of abstraction removed from the actual Game of life states.

The page you linked runs the code in a Javascript implementation of their CPU. That's a significant shortcut. The CPU was otherwise implemented with logic gates that were implemented with varlife circuits that were implemented with metapixels in Game of Life. None of this is present in the browser implementation.

As logicallee's comment below says, the actual Game of life board behind the implementation is absolutely massive with tens of gigabytes needed to represent the state of the Tetris computer.

teekert
That is just one of the coolest things I've seen which makes me feel a bit strange inside. Like looking the universe into the soul. Like feeling how simple thing can produce complex things (but not understanding). Thanx for sharing.
I'd guess that GoL and Cellular Automaton Theory preceded and inspired rule 30 etc. So, maybe the architects implied metarecursion, that GoL metaphorically generated rule 30.

GoL is Turing complete. I guess that means there is a starting condition that converges to a rule30 cellular automaton.

edit: video of GoL emulated inside a turing machine in GoL https://www.youtube.com/watch?v=xP5-iIeKXE8 (link replaced)

My favorite: https://www.youtube.com/watch?v=xP5-iIeKXE8
bbcbasic
VM life
bbcbasic
huh? downvote? the link is a virtual machine in Conway's Game of Life.
Dec 31, 2016 · 51 points, 11 comments · submitted by Moshe_Silnorin
Moshe_Silnorin
Watching this is the closest thing I've had to a religious experience.
georgeecollins
OMG!

The first program I did in my Bally Astrocade so many years ago was Life. I remember thinking what a dream it would be to be able to run a 100x100 grid at one generation per second. I could not have dreamed of this.

imperialdroid88
https://www.youtube.com/watch?v=iiEQg-SHY1g&t=58s

I found this to be a really cool interpretation of the game of life, as the computation creates a visible state.

JoeDaDude
People who are intrigued by Conway's Game of Life and cellular automata (CA) in general may enjoy tinkering with them in Golly [0], an open source sandbox for CAs.

[0] http://golly.sourceforge.net/

JoeDaDude
The Game of Life is probably the first program I ever wrote. I (somehow) managed to get it working on a Timex Sinclair 2068 using a BASIC compiler which could only support one dimensional arrays.
tandav
It shows the recursion of our entire universe.
noonespecial
That was a beautiful thing. Thanks for posting that. Made my day.
lend000
Cool video of self organization, which led me to this: https://www.youtube.com/watch?v=1X-gtr4pEBU
Lina_222
.
Lina_222
что это
espeed
From the comments, see...

OTCA Metapixel - Conway's Game of Life http://www.instructables.com/id/OTCA-Metapixel-Conways-Game-...

http://www.conwaylife.com/wiki/OTCA_metapixel

https://en.wikipedia.org/wiki/Moir%C3%A9_pattern

https://thewalnut.io/visualizer/visualize/3631/987/

Jul 07, 2016 · pkaye on Wireworld
I find this to be quite amazing. Life within life. https://youtu.be/xP5-iIeKXE8
Sure, you can do Game of Life in Game of Life :) https://www.youtube.com/watch?v=xP5-iIeKXE8
Nov 17, 2015 · ingenter on OTCA metapixel (2010)
A video depicting a glider moving in metapixels.

https://www.youtube.com/watch?v=xP5-iIeKXE8

See also, Gemini, self-replicating ship going the path of universal constructor: http://www.conwaylife.com/wiki/Gemini

Apr 22, 2015 · 1 points, 0 comments · submitted by sumitviii
Aug 22, 2014 · 7 points, 0 comments · submitted by jpatokal
Game of life simulating itself.

https://www.youtube.com/watch?v=xP5-iIeKXE8

http://www.conwaylife.com/wiki/OTCA_metapixel

Minecraft in Minecraft

https://www.youtube.com/watch?v=GwHBaSySHmo

Xenmen
Thank-you so much for sharing Life in Life!

It's the perfect way to convey how complicated transistor-level emulation is to design...

tim333
Yeah pretty cool, apart maybe from the soundtrack
tgb
The soundtrack is a Shepard tone and is actually pretty cool too!

http://en.wikipedia.org/wiki/Shepard_tone

fhnjh
The game of life simulation is definitely ready for another layer of meta, GOL simulating GOL simulating GOL...
michaelmior
Once you know how to simulate GOL within GOL, you can go as deep as you want.
Houshalter
It's turtles all the way down: https://www.youtube.com/watch?v=D6aP9S9rEQk
sbierwagen
According to the description, this was done with video editing, rather than an actual running nested simulation.
Houshalter
It is a simulation of Game of Life in Game of Life. They did loop the video though. Obviously it's not possible to fully simulate such a huge machine. You could do it with sufficiently clever optimization, but the result would be equivalent to video editing.
readerrrr
A period of a single cell would take 35328^2 periods and (2048*2048)^2 cells of the most underlying game of life simulation.
nitrogen
A Life acceleration algorithm would help with that, but each cell would still require 4Tb of storage (though that storage could be shared by all cells, II think).

https://en.wikipedia.org/wiki/Hashlife

readerrrr
And there is not real purpose since the rules are the same for every level. Making them different and more complex would be interesting.
boyaka
Computers in UNIX

http://www.linusakesson.net/programming/pipelogic/index.php

Not only that, but it can find lowest common denominator, solve a system of linear equations, and even run the complete RSA algorithm (albeit with a pseudorandom RNG that's deterministic).

Or run a game of live's simulation http://www.youtube.com/watch?v=xP5-iIeKXE8

What about making Conway's Game of Life in Conway's Game of Life?

http://www.youtube.com/watch?v=xP5-iIeKXE8

Gormo
This is brilliant. It's not even a "logic puzzle" as much as it is an engineering feat.

And it's not like software engineering, where you're defining the nature of the system as a whole, and then instantiating it, but more like a physical engineering discipline, in which you're juxtaposing already-existing materials against each other such that their pre-existing properties interact with each other to produce the behavior you want.

gidan
Conways' Game of Life is not a strategy game. I built one using Javascript:

http://jules.boussekeyt.org/game-of-life/

(instructions: click on some squares and press "Start")

pearjuice
It certainly has a strategy element seeing as the whole game is build upon the premise that particles act depending on a certain strategy.
None
None
lcedp
The logic is mind blowing. That's similar to what I imagine to be programming of nanodevices in the future.
Apr 10, 2013 · 1 points, 0 comments · submitted by adrianhoward
Dec 06, 2012 · 1 points, 0 comments · submitted by jonmrodriguez
no computer can do that of course.

we are getting there - http://www.youtube.com/watch?v=xP5-iIeKXE8

eru
And you can run that in real time on a desktop. The secret is a hash life approach.
scrumper
Outstanding, thank you for this. Worth a post on its own don't you think?
saraid216
That's the video in the same blog if you click "Previous": http://www.jwz.org/blog/2012/05/turtles-all-the-way-down-or-...
DanBC
It had one, 4 months ago. No comments, only 4 points.

(http://news.ycombinator.com/item?id=4014078)

I think I've seen it before that too, from HN.

Jul 26, 2012 · 6 points, 1 comments · submitted by jgrahamc
NHQ
that is totally awesome
May 23, 2012 · 6 points, 0 comments · submitted by anigbrowl
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