AMA: I'm Dave Greene, an accidental expert on Conway's Game of Life | Hacker News Reader

AMA: I'm Dave Greene, an accidental expert on Conway's Game of Life

313 pointsdvgrn151 comments

I drifted into the Conway's Life research community in 2001 when I won a small cash prize for a lucky discovery of something called a "boojum reflector". My involvement has gradually snowballed since then. Off and on I've helped maintain various Life-related mailing lists and blogs, the Life Lexicon, and more recently the conwaylife.com forums and LifeWiki.

Another thing I stumbled into was helping Nathaniel Johnson complete an improbably thorough 480-page Conway's Life textbook, with end-of-chapter exercises and everything. The book could be used to teach a college-level class on the subject. https://conwaylife.com/book/ has a free PDF download for the book.

So... I'm not the cleverest Lifenthusiast by a long shot, but for a random question about the Game of Life, I'm more likely to know something about it than at least 99.9999% of the world's population. Ask me anything!

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We see people doing insane things nowadays with Conway's Life, such as simulating CPUs.

Two questions:

1) How are people building things this complex? Are there open source libraries and toolkits for this - building blocks for chunks of functionality that can be assembled?

2) For you, what are the most interesting, impressive and varied things that you've seen with Life? Is it just these increasing levels of complexity, or maybe something else?

Question 1: There are really surprisingly few "standard libraries" or tools for this kind of thing. You would think we'd have a CA editor capable of doing object-based editing by this time -- like, copy in a complete device made out of reflectors and converters, each of which is made out of still lifes and oscillators, each of which is made out of cells, and you could do "group" and "ungroup" operations and snap to the right locations to fit the circuits together correctly.

But at the moment, pretty much all we have is tools to copy and paste rectangular sections of patterns at the cell level -- plus we've got good scripting tools (in Golly) that can be used to string together whatever pieces we might want, but it's up to individual pattern-builders to write those scripts for each specific purpose.

So our "library" is pretty much just the LifeWiki and a few other pattern repositories, and we borrow liberally from existing large constructions -- but when we're building something new, we usually just build flat bitmaps, not anything with built-in annotations or metadata.

Question 2: The thing that's been the most interesting to me in the last decade or so is the increase in collaboration. Projects used to be done by just one person more often than not -- but now a very large fraction of the biggest discoveries are completed via a large group effort over the course of a few weeks or month. One big recent example has been the RCT fixed-cost universal glider synthesis project, which needed contributions from quite a few people to solve all of the tricky little sub-problems:

  https://conwaylife.com/wiki/Reverse_caber-tosser

The Game of Life is a 2-dimensional cellular automata (CA), so given the 1-dimensional rule 110 has been proven to be universal / Turing-complete [1], it becomes less mysterious. Albeit the complexity of the system required to set it up to do anything "useful" would be prohibitive.

I'm currently finishing up my OU MSc and the project I picked was specifically around cellular automata - only in this case relating to them calculating any arbitary automatic sequence - which are sequences you can create from finite state machines - that really opened my eyes to the fact these sorts of very, very simple machines can, with the right (and rather complex) setup, be made to do pretty much whatever you want from a computational PoV. In that paper by Rowland and Yassawi they give a constructive proof to calculate the required update rules for a CA that outputs any particular automatic sequence. That itself gives some hints at some ways of deriving the input and rules for these systems to do some particular job. [2]

I know Wolfram often gets dunked on for ego/hubris but in Chapter 11 of a New Kind Of Science he goes into how the Rule 110 CA can be setup to "calculate" (output) other CAs. From there it starts to become a little less mysterious that these systems can generate behaviour you could imagine running on a CPU of some sort.[3]

[1] https://mirror.explodie.org/universality_in_elementary_cellu...

[2] https://arxiv.org/abs/1209.6008

[3] https://www.wolframscience.com/nks/chap-11--the-notion-of-co...

The basics, JIC anyone here is still unfamiliar with the Game:

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

And generalizing Games from there:

https://en.wikipedia.org/wiki/Life-like_cellular_automaton

Question #1: How far has Lifeology(?) advanced since 2001, for people similar to your younger self (without awesome skills, or huge time investment) to have a chance at making their own lucky discoveries, and becoming modest Somebodies in the community?

Question #2: How highly (or otherwise) would you rate Wikipedia's articles on Conway's Game of Life, and closely-related topics?

A really impressive number of discoveries have been made since 2001 -- there's been kind of a proliferation of new sub-fields, so it seems like there's never any shortage of things for newcomers to work on.

There are definitely areas that haven't really been explored fully yet, like the use of SAT solvers in new and inventive ways to tackle difficult Life problems that are currently just beyond our reach.

Just for example, there's the problem of finding a fast elbow for a 2c/3 "signal wire" --

  https://conwaylife.com/wiki/Wire#2c/3_wire

It's not clear if SAT solvers can be applied usefully to glider synthesis questions, like "is it possible to collide gliders to build a Sir Robin spaceship?" At the moment that particular question seems way beyond reach, but maybe in a few years we'll be running an AI that is experimentally setting up new SAT solver problems, and something will pop up that we just haven't managed to think of yet.

Question 2: Wikipedia's articles tend to be very good quality -- partly because if they weren't, there are a lot of Lifenthusiasts with some experience maintaining the LifeWiki who would immediately go and fix any technical errors that might show up on Wikipedia. But the really detailed documentation on Life is definitely kept in the LifeWiki, not on Wikipedia:

  https://conwaylife.com/wiki/

Reminds me of the Busch-Gass Gambit in chess - something so new and mind boggling that it absolutely destroys the best chess engines in the world. Discovered through computer analysis. Insane to watch this opening played well.

>Humans have not beaten the top chess engine of the time in a “serious” game since around 2005.

https://ppqty.com/anyone-beaten-stockfish/

The qualifier "serious" is needed because GM Andrew Tang won games at hyperbullet time controls (15 seconds) against a weaker version of Stockfish.

Article is dated Oct 2023.

>it absolutely destroys the best chess engines in the world.

Citation?

I'm willing to believe that someone used the gambit to win against an engine, but in response I would've expected the engines to be modified to restore their absolute dominance against human players.

So, I would be very interested to see any evidence that this gambit continued to work against the version of the engine released after the gambit's effectiveness became widely known.

Play it for yourself against the current stockfish.

I was unfamiliar with JIC, had to read the sentence twice to make sense of it. :-)

Have you followed the https://codegolf.stackexchange.com/questions/11880/build-a-w... thread where Tetris was implemented using their Cogol (and low level QFTASM) programming language? I'm curious if that work led to any new insights and if it found any usage beyond implementing Tetris.

Yup, the Quest for Tetris project caused an entertaining stir for a while. The people that worked on that were the best kind of "hacker" -- fearless experimenters who didn't let their lack of Life-specific knowledge get in the way of cobbling together an amazing structure that fit the bill for simulating Tetris.

The project has at least one unnecessary extra layer of abstraction in it, but somehow nobody has quite gotten around to rebuilding it 100x smaller. A "HashLife-friendly" version could run thousands of times more quickly in Golly.

Since then, several people have invented their own independent computer architectures in Conway's Life, so that kind of experimentation is still going on. See, e.g.,

  https://conwaylife.com/wiki/8-bit_programmable_computer

Thank you!

Why is Conway's Game of Life so interesting? Does it prove anything or lead to insightful discoveries? The game itself seems to me, like a fun little toy at best.

This won't directly answer the question, but just to give some added context: Note that in abstract mathematics (which is what Conway was doing here) you’re kinda creating building blocks, and you're kinda playing for “street cred” among the rest of the abstract mathematics community.

This is kind of true in all academic publishing, that your success is due to your publications’ ability to inspire follow-up publications. But for abstract mathematics the “street cred” follows three rules: you get more cred based on,

• the wimpier the building blocks look

• the larger and more complex the structures you can build with them

• the more memorable or intuitive the blocks are (so like marketing... SK-calculus is the same as lambda calculus but lambda can say “I am the abstract mathematics of template substitution!” while SK-calculus can't, directly.)

All a way to say that the field is full of “fun little toys” and the key about criterion (2) is that we have figured out how to build structures of arbitrary complexity in Life, because we have discovered it is Turing-complete. It therefore is also NP-hard and a lot of other good stuff. Really revitalized work into cellular automata by giving some good marketing, which led to Stephen Wolfram's success etc etc.

Excellent info.

> which led to Stephen Wolfram's success etc etc.

Wolfram's A New Kind of Science takes the idea a bit too far, in my opinion. It's an exposition of the hypothesis that the underlying stratum of life and the universe is, like cellular automatons, discrete—and therefore can be understood in terms of discrete processes, which he views as analogous to real life. He points to emergence in cellular automatons as evidence that an analogous emergent phenomenon was the reason biological life came into existence.

Mathematically and philosophically, it's a very interesting idea, but I'd hope that at this stage in scientific history, we'd understand that step 2 to validating an interesting hypothesis is testing it.

yeah wolfram's famous idea (which is sort of the whole point behind a new kind of science) is this computational equivalence principle which is that most things that are at a certain level of computational complexity are equivalent to each other[1]. Which may be true in some limited sense but is definitely not true in the general sense that he tries to imply. This has led him to saying things like you can implement the whole universe "in 4 lines of the wolfram language" even though mathematica (which is in the universe and implements the wolfram language) takes more than 4 lines of code to implement.

[1] https://mathworld.wolfram.com/PrincipleofComputationalEquiva...

Boring mathematicians of the school of actual concrete formalisations level the criticism that his Principle of Computational Equivalence is never given a formal definitive statement and is more of an aspirational feel good kind of fuzzy wuzzy thingy.

eg: Lawrence Gray in his 12 page review: https://www.ams.org/notices/200302/fea-gray.pdf

Cosma Shalizi's infamous Rare Blend of Monster Raving Egomania and Utter Batshit Insanity review: http://bactra.org/reviews/wolfram/

A simple set of rules leads to a fascinating array of emergent phenomena, which themselves can be utilized to do all sorts of interesting things.

In fact, the game of life is Turing complete -- you can build whole processors[0] or programming languages in it. You can even implement the game of life in the game of life. Someone did that and implemented infinite zooming between GOL levels.[1]

[0] https://github.com/nicolasloizeau/scalable-gol-computer

[1] https://oimo.io/works/life/

It shows that complex structures, importantly those with generative capabilities and other utilities, can evolve from a simple pattern.

It's a fun toy because it's implemented in pixels with arbitrary rules, but the concept is exportable to other domains.

The eeriness of it I think comes from that we still don't understand a lot about the world - concepts like consciousness, the origin of the universe, origin of life - or, any mystery where we don't understand how a whole became greater than the sum of its parts - when you see a model like this, it shows visually how such unknown complexities probably originated in far simpler forms.

When I see those epic Game of Life videos where there's a giant stealth bomber looking structure steaming across the screen creating sub-processes in its wake, to me it's like a blue whale moving through the ocean, or a vast alien spaceship silently yet steadily barreling through the void of space.

There's an ominous intelligence that seems to emerge out of what was once simple, binary, unconscious, incapable.

Conway's Game of Life (GoL) provides a clear demonstration that simple rules can lead to complex behavior. The complex behavior is deep in the sense that Conway's GoL is Turing Complete [0].

The local update rules provide an analogy to our universe with a kind of built in "speed of light" of how fast information can propagate in the system. Further, since there is a system clock of sorts, the system is massively parallel with further analogies to our universe.

The game looks like a toy but note that many profound models are also "toy-like". Ising systems, precolation models, Bethe lattices, self avoiding walks, etc. all provide seeding grounds for deep insights into our physical world. Just as an aside, I heard a quote, which I can't find anywhere, about how Maxwell playing with magnets could have been considered him playing with frivolous toys but his setup was critical to him figuring out the underlying mechanics of electromagnetism.

On one hand, I sort of agree that there's a lot of uninteresting exploration but on the other hand, taking a step back, GoL research is exploring the more general space of cellular automata and how it could potentially map to real world simulation. For example, how small can a system be before it can do arbitrary computation? Can all patterns emerge eventually (no, garden of eden style patterns)? What do rotationally invariant patterns looks like? Can you "copy" arbitrary patterns from some setup? If so, how fast? Is it dependent on how big it is, or how complex it is? etc. GoL provides a sandbox in order to answer these questions and potentially give insight into other systems as well.

In my opinion, one of the reasons for the popularity of GoL is because it was created right when computers became commodities, allowing hackers, amateur mathematicians and others to program something simple, that could be heavily optimized for limited hardware, and create intricate and complex behavior. There was a quote somewhere, that I'm also having trouble finding, about how, at one point, GoL simulations accounted for a significant portion of wasted compute.

[0] https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life#Undeci...

Just leave physics out, and you’ll be OK.

God doesn’t play the GoL.

It's a cellular automaton showing complex behavior emerging from very simple rules. Through especially crafted inputs you can simulate a Turing machine or Conway's Game of Life inside itself.

> boojum reflector

That absolutely sounds like a codename from one of cstross's Laundry Files novels. (I think "boojum" was actually part of one, but I don't recall which.)

edit: found it, it was from A Colder War, which is a great novellette: https://www.infinityplus.co.uk/stories/colderwar.htm

The word "boojum" originates in Lewis Carroll's "The Hunting of the Snark," an amusing epic poem about the importance of negative testing.

I'm interested. Scanning wikipedia, I'm missing the link with the importance of negative testing. Could you explain?

Positive testing, in this case, is matching a sample to a pre-existing pattern

Negative testing is trying to invalidate the sample

The hunting of the snark is written in a way that reads like "normal English" from a distance. The sentences flow fine, the words look about right if you squint. So it passes a lot of "positive tests", in that it matches our expectations for what language looks like.

You have to "negative test" the story to realize you don't know the definitions for any of the words, and that the plot is uninterpretable.

Same idea as Kahneman's system 1 that comes up with instant answers, or ChatGPT hallucinating facts by association that "look right".

Reminds me of Ted Hughes' Wodwo, playing with the concept of the known, unknown, and unknowable.

It challenges the reader to try to model and define a Wodwo, but provides basically no information on what a wodwo is, aside from the fact that it is something that itself is struggles to define it's relation and connection to the world.

In my opinion, it highlights how we are all physical perception machines looking for meaning and identity, but meaning and identity can not be physically perceived.

https://allpoetry.com/poem/8495307-Wodwo-by-Ted-Hughes

Yes, please -- I'd like to hear more about that! I've got the poem memorized, but mostly what I know about it is that Carroll thought of the last line first --

"For the Snark _was_ a Boojum, you see."

and ended up writing the other umpteen dozen verses just so that that would make sense as a punch line.

Sorry, that was a joke.

The Snark is described in detail, with but a single additional caution that some Snarks are Boojums, with no description whatsoever of the difference. And, in the end, only a Boojum is found.

The band of snark-hunters are _also_ described in detail, almost always emphasizing the things that they cannot do or the additional risks of having them along, but they're brought along anyway.

And also is given to a cactus-like tree: https://en.wikipedia.org/wiki/Boojum_tree

I've been fascinated by Cellular Automata and the Game of Life ever since seeing the art installation of _Network IV_ by James Seawright. It was at Sea-Tac Airport, and has since been removed.

There's some debate whether it was the Game of Life or some other automata, but I remember the sounds of the relays clacking and the light bulbs humming so distinctly. It certainly had a "Game of Life vibe".

Are you aware of this art installation? Ever seen it?

Hadn't heard of it. Looks like it was removed sometime in the 90's, maybe, so it's not too likely that there would be a good video of it in action.

https://www.reddit.com/r/Seattle/comments/1xzypl/something_i...

https://imgur.com/gallery/3zwVKc3

It does seem like the kind of thing I might have been drawn into staring at for hours and/or playing around with, kind of like the marble perpetual-motion machine I remember from a Toronto museum at around the same time period.

Conway has said GOL is not something he is particularly pleased got as famous as it did. (Ref: https://youtu.be/R9Plq-D1gEk?t=600)

Why do you think that is?

Edit: This is the video I meant: https://www.youtube.com/watch?v=E8kUJL04ELA

What I got from his interviews is not that he disliked the GoL, it's just he disliked the GoL overshadowing everything else he did (basically, becoming the GoL guy). He personally didn't see much more interesting mathematics that could be done after answering basic questions like universality (although it's likely he wasn't aware of everything the community was up to). Also, it's clear he seemed to come to terms with it in his final interviews (including the second one you linked) :)

I've played around with several CAs and Conway's rules stands out to me as one of the most interesting still, for many reasons (like simplicity, interesting patterns, long lived structures).

Reminds me of Steve Paxton, an amazing dancer who passed away recently. He led a project called “Contact Improvisations”, which became a movement form called Contact Improvisation. He taught some classes and many others contributed. 50 years later, it’s still going strong. But, he didn’t embrace this role of “Contact Improv guy” that was really available to him. He just kept doing other stuff, even as this community exploded.

I think that’s partly the nature of pure researchers. They usually have something more interesting to them than what they got famous for, and they probably don’t want to lead an organization. This is different from BDFLs like Guido van Rossum and Rich Hickey. Neither type is good or bad, and I appreciate them all.

It's almost by definition that if you get popular for something, it is not the thing you're most interested in or best at - because you're an expert in the craft and for something to be popular it has to be at least somewhat approachable by non-experts.

A silly question and a PSA:

1. There was a two-player game called The Immigration Game [1] using GoL rules. Has anyone actually played this? Even better, has anyone developed an AI to play it? Is there really much of a game there?

2. The PSA: The Immigration Game was described in Lifeline, a 1970's era (typewritten!) newsletter about GoL. I managed to obtain a set of them. I've been planning to scan them and make them available online. I don't think there is any ground breaking info in them, after all, folk were programming on mainframes (surreptitiously).

[1]. https://boardgamegeek.com/boardgame/129088/the-immigration-g...

My sense is that people don't usually play the Immigration Game for very long -- it just doesn't seem all that interesting to most folks ... and so there hasn't been much interest in developing a computer opponent for the game.

It seems to be rather difficult to convert cellular automata into any kind of playable game. If it's an arcade game then it's usually too arbitrary, and if it's a puzzle game then it's usually way too easy or way too difficult. There have been some good efforts, but they're mostly only playable by dedicated Lifenthusiasts, and that's ... well... not a very large market!

Re: the LIFELINE public service announcement -- no need to do the scanning and online-ing. That's been done already, though there's still some review and typing-up work left for someone to do:

  https://conwaylife.com/wiki/Category:Lifeline_issues

Decades ago, I read an article in Byte magazine discussing various implementations of GoL. The article ended with an implementation in one line of APL. What are the chances you (or anyone) still has that article, and that one line program?

Heh -- "if you need more than one line of APL you do not fully understand your problem".

  https://news.ycombinator.com/item?id=1041500

People have done similar things in all kinds of languages by now:

  https://codegolf.stackexchange.com/questions/3434/shortest-game-of-life

This video constructs a GoL in APL (not one liner). It is quite understandable even if you don’t know APL (I had just started tinkering with APL when I first found it I think): https://m.youtube.com/watch?v=a9xAKttWgP4

In case somebody is curious to see how it might look like.

    life←{⊃1 ⍵ ∨ .∧ 3 4=+/,¯1 0 1∘.⊖¯1 0 1∘.⌽⊂⍵}

and if you want some additional explanation:

https://aplwiki.com/wiki/Conway%27s_Game_of_Life

Is there a 3d equivalent of the game? What would be different about it?

There's been quite a lot of experimentation with 3D versions of Conway's Life -- including rules where you can easily emulate Life on a 2D slice of the 3D plane. Carter Bays did some investigations and published papers back in the 1980's:

  https://conwaylife.com/wiki/Three-dimensional_cellular_automaton

There's been a little bit of revived interest lately, when newer versions of Golly ( https://golly.sourceforge.io/ ) started to include at least some support for 3D rules. Other programs have been showing up recently, though some of them are more ways of visualizing the history of a 2-dimensional rule in three dimensions.

There are a couple of big difficulties that seem to prevent 3D rules from getting a lot of attention. It's just plain a lot more computationally intensive to emulate 3D rules. Also it's a lot harder to see what's going on in the middle of an active 3D pattern -- a lot of the detail tends to get hidden.

Carter Bays wrote a paper "Candidates for the Game of Life in Three Dimensions" on that back in 1987 [1] and another in 2006 as mentioned on Wikipedia [2]:

[1] https://content.wolfram.com/sites/13/2018/02/01-3-1.pdf

[2] https://en.wikipedia.org/wiki/3D_Lifex

This was posted yesterday: https://news.ycombinator.com/item?id=40124682

What are the coolest problems that have been recently solved?

What are the coolest open problems you'd like to see solved?

It's hard to choose one these days -- a whole pile of open problems actually got solved in the last few years, like omniperiodicity, glider syntheses of really complicated things like spacefillers, fixed-cost universal construction (it only takes fifteen gliders to build anything buildable) and still lifes and oscillators that solve the "unique father problem" (i.e., there are groups of cells that, if they're found in the Life universe at any point, they must have been there from the beginning of time.) So now I don't know what to wish for next!

I suppose if I get a free wish for anything I want, I'd love to see a glider synthesis for Sir Robin, which a big oblique spaceship discovered in 2018. It's currently way beyond our ability to figure out how to build it out of gliders -- but twenty years ago the same was true of just about every Life spaceship, and now we have recipes for dozens of them.

> fixed-cost universal construction (it only takes fifteen gliders to build anything buildable)

Here’s the Hacker News discussion from when this was discovered: https://news.ycombinator.com/item?id=33797799

Dave, I’m still regularly blown away by this discovery. I don’t know what else there is to be said, but do you have any other comments regarding this?

Definitely I have lots more to say about 15-glider universal construction! It was a really exceptionally interesting collaboration, where several people working together were able to complete something that would have taken any one person a ridiculously long time to sort out.

Development of the RCT has slowed down a bit, though there's a hyper-optimized version in the works that will build a spacefiller instead of a Hensel decimal counter as its example pattern:

https://conwaylife.com/forums/viewtopic.php?p=180134#p180134

There's also another long-awaited project in the works, that will use quite a bit of the same technology along with some new ideas -- a unidimensional (one cell thick) spaceship:

https://conwaylife.com/forums/viewtopic.php?f=2&t=2040

It's improbably complex and awkward, of course, just like an RCT pattern, and it's huge though nowhere near as huge as an RCT pattern -- but there will be one phase of the spaceship that fits in a 1xN bounding box.

What would that investigation look like, just large amount of trial and error?

It's going to have to be the opposite of trial and error, I would think -- though maybe in some sense some of the underlying searches for useful predecessors of patterns like Sir Robin could count as "directed super-high-speed trial and error".

The problem at the moment is that nobody can see how to direct those searches toward a predecessor that's made entirely out of gliders -- it's clear that the Sun will burn out long before a trial-and-error search would be at all likely to return a result.

We can easily make a huge number of non-Sir-Robin predecessor patterns that will evolve into Sir Robin -- and we can find ancestor patterns for most of those predecessors, too -- but each step backward always produces something that's a little bigger, a little blobbier, and a little more random and chaotic looking than Sir Robin was... so ultimately all we're doing is making the problem more difficult with each step.

What’s the largest world we can run these days?

Are they run on gpus now?

Has anyone looked into ASICs?

Is caching heavily used for optimization?

Yup, there's an increasing amount of GPU use these days, mostly related to soup searching -- see https://catagolue.hatsya.com/home for the software and a tabulation of results from the last several years of collaborative searching.

Caching is very very heavily used for running the biggest universes, which are truly mind-bendingly large. Golly's "HashLife" algorithm can in practice handle patterns that are over a trillion cells in each dimension:

  https://conwaylife.com/forums/viewtopic.php?&p=153609#p153609

Patterns with interesting behavior very often have a lot of repeating patterns, with the interesting stuff happening as complex interactions between those predictable patterns. HashLife capitalizes on remembering interactions that it has seen before, so basically the more memory your computer has available, the better HashLife will do in the long run at simulating that type of pattern.

I'm curious at the term "soup searching": is this just looking for particular shapes? Or shapes that have certain behaviors?

"Soup searching" generally means not looking for anything in particular. It just involves setting up a random initial configuration, letting it run until it stabilises ("goes boring") and then takes a census of what's sitting around in the ashes of the burned-out pattern.

Mostly, of course, the census just reports piles and piles of blinkers and blocks and beehives and boats and everything else that you almost always see when you run a random scribble -- but every now and then something turns up that has never ever been seen in the history of Life, and that turns out to be useful and building new mechanisms that weren't possible before:

  https://mathematrec.wordpress.com/2016/07/05/richs-p16/
  https://conwaylife.com/wiki/Rich%27s_p16

Not a question but as a fellow Life enthusiast I thought I’d surface an alternative Life hack I made a few years ago based on physical Kong Bucks from Stephenson’s Snow Crash: https://kong.cash/

Each note is an actual flexible polyimide PCB containing a hardware storage wallet - the PCBs are translucent in parts or solid in others depending on a copper pour but overprinted with ink using a special UV process - but one of the security features is when one holds a note up to the light one can see a Game or Life program which when executed emits a corresponding number of gliders and oscillators as the notes value. This feature is to prevent one from “washing” a note and printing a different value as is done with $5 and $100 US bills for instance as the copper pour is “baked” into the medium.

Writing a c program to encode arbitrary numbers into a Game of Life program was a very fun distraction during an otherwise thorny project that involved connecting people from the print world to people from the electronics world while shaving a few thousand cycles off a crypto library with ECDSA P256 operations before the smart phone powering the chips via NFC turned off. Real engineering work to bring cryptographic proof of authenticity that unfortunately gets written off as a 'crypto scam' when the poc token attached to the circuit boards was the least interesting part.

One can see some of the denominations here: https://twitter.com/NoviolNFT/status/1341468948416512000

What's your take on continuous life? SmoothLife, Lenia and Bert Wang-Chak Chan work in general?

I think SmoothLife and Lenia are great fun -- lots of highly watchable "eye candy" tends to get produced by those types of experiments. The better you get at running experiments, the more new behavior you can turn up:

  https://www.youtube.com/c/Slackermanz

There's a channel on the ConwayLife Lounge on Discord called "#exotic-ca" that's devoted to these kinds of explorations. I just simply haven't had time to dig into those topics much, but if I could clone myself I'd definitely assign one copy to playing around with that kind of thing.

Over the years there must have been countless interesting generalizations of Life. I wonder if there is good concise reference that classifies and groups the main ideas that have been proven "productive", in the sense that they open up non-trivially different and interesting types of dynamic behavior?

A while ago I was toying with the idea of introducing a "macro" stimulus. Basically coupling the local rules of the game to global metrics like how many nodes are alive. This is emulating a bit agent based modeling in economics and in particular the role of regulators raising or lowering rates, alternatively a physical system exposed to higher or lower temperature. But what happens (at least with a simple implementation) is that whatever "stimulus" is introduced tends to overwhelm the known patterns, there seems to be little new "emergent" behavior in the coupled system.

https://www.openriskmanagement.com/game_of_life_with_macroec...

I don't know about "concise", but one place to start for references is the LifeWiki. We've been trying to extend the non-Conway's-Life part of the wiki for a few years now, to cover more of the OCA space ("Other Cellular Automata"):

  https://conwaylife.com/wiki/Cellular_automaton
  https://conwaylife.com/wiki/OCA

There's an "Other Cellular Automata" board on conwaylife.com/forums and several channels on the ConwayLife Lounge on Discord -- "#naturalistic", "#circuitry", "#exotic-ca" -- that collect discussions on these kinds of topics.

Thanks for the pointers. Nonlocal cellular automata do not seem to be an active area but I did find one old publication by Wentian Li.

https://scholar.google.com/citations?view_op=view_citation&h...

1. Are there any practical/real life applications for Game of Life?

2. Has any discovery made in life been used in real life or any practical application?

It's great for generating synthetic data for training LLMs for solving Abstraction & Reasoning Corpus (ARC) by François Chollet. Game of life helps the LLMs with a 2D understanding of the world.

https://github.com/fchollet/ARC

This is like asking about the practical applications of chess. They're probably mostly nth-order effects.

Heh, yes, the comparison to chess is a very good one. You probably need a similar level of focus and dedication to be a good Life pattern engineer or a good chess player -- and that level of focus is something that improves with enough practice, in both cases.

I've mentioned in other answers that Life can make a good teaching tool for various mathematical and computer-science topics, mostly because it's entertainingly eye-catching. When you get a design right it's very satisfying -- like one of those huge domino chains that you see on YouTube, except that (for some designs) it keeps on setting itself back up again as it's in the process of falling down.

What would be your advice/roadmap for someone who wants to start with automated exploration of emergent behaviour in systems that are similar to GoL?

I think it would be interesting to try transfering some of the automated search techniques to Minecraft's redstone mechanics, even though it probably doesn't fit the definition of a celular automata. Redstone is a feature in a videogame Minecraft that acts similar to logic circuits. Because building mechanics in Minecraft is inately restrictive (building is snapped to the 3d grid of "blocks", and there is only a limited number of blocks that all have predefined behaviour), there is naturally a community of people using redstones in ways that serve no purpose to the core gameplay loop, such as flying machines (think GoL's ships) [0], computers (since Minecraft's redstone is practically Turing-complete) [1] [2] or printers/autobuilders [3]. I would go so far as to say that redstone is the GoL for nerdy Zoomers.

[0] https://minecraft.fandom.com/wiki/Tutorials/Flying_machines

[1] https://www.minecraftforum.net/forums/minecraft-java-edition...

[2] https://minecraft.fandom.com/wiki/Tutorials/Redstone_compute...

[3] https://minecraft.fandom.com/wiki/Tutorials/Printing

I'm thinking the most successful "automated exploration" so far has been Catagolue's method: simply generate a whole lot of random-soup initial configurations, run them until they settle, and then poke through the ashes looking for interesting stuff:

  https://catagolue.hatsya.com/census

Seems like that gets the most emergent-behavior bang for your buck. All the other "automated search techniques" that I can think of are too specifically tailored to some particular problem.

Thank you for the link to the book. I have always been interested in how to make the starting shapes. I am going to study the book more but started to realize that there are re-usable shapes that can be used to make more complex shapes (early, still, oscillators, gliders, etc..). This seems to be what I was looking for with the starting x/y and then the rule combo and pattern.

I was also thinking there must be a better way than knowing exactly how big the board is vs an infinite board. Also making the edges either always dead or alive VS letting the shapes pass through like pac-man.

Here is my horrible implementation using HTML canvas, JS/JQuery.

https://github.com/JoshuaMichaelHanson/GOL/blob/master/js/go...

Yes, I also made a new green account so as to not dox myself with my other accounts.

I haven't studied CS or bio. Do I understand correctly that what makes cellular automata special is they're approachable and demonstrate how complexity can emerge from simple rules (e.g. analogously to how life may have come to be)?

Do other games (or simulations) demonstrate similar ideas, or are cellular automata a rare case?

I'd say there's no shortage of demonstrations of complexity emerging from the iteration of simple rules -- fractals like the Mandelbrot set, simple edge-matching rules for aperiodic tilings, the logistic map, etc., etc.

What makes Conway's Life particularly "catchy" (along with other 2D CAs) seems to be the motion. Humans love watching stuff move, especially when the motion is partly predictable and partly surprising -- i.e., like a screen-saver, not like TV static. And they like watching things blow up. A lot of Lifenthusiasts probably got their start by aiming gliders at carefully balanced Life patterns and gleefully watching the resulting explosions... it's a lot more fun than actually blowing things up, because you can always hit Undo and run it all over again, no harm done!

Not sure that "being able to hit undo" and "no harm done!" is what makes blowing things up enjoyable, but to each his own.

Heh, well, I'm speaking as somebody who was fairly obsessed with making Rube Goldberg domino chains as a kid, spending hours at a time covering a large oak trestle table with precarious stacks of wooden blocks, rulers, tape cases, strings, marbles and so on -- and then knocking them all down. (This was long before YouTube, so I don't have any documentation of any of this.)

I would really have appreciated an "Undo" button for rewinding entropy and running those things over again, especially when they went disappointingly wrong halfway through...!

I discovered Langton ants and Turmites a couple of months ago, I guess these are a subset of cellular automata. I was talking with a friend about using them somehow for art somehow (music generation came to mind), is this a topic you might know about and could recommend some resources to get started?

Langton's Ant is one of many, many CA rules that run for a while, seeming to be "predictably unpredictable" -- creating lots of blobby chaos -- but then produce a highly recognizable emergent phenomenon (the final "highway", in this case).

For music generation you'd want to somehow avoid ending up with the music "going boring" when the highway appears... As with a lot of math-inspired art (I guess I'm thinking about Mandelbrot-set colorizations here) the key is going to be in very specific presentation choices -- color choices for still frames or videos, or the specific method of mapping sounds to frames in a Langton's Ant evolution. So you'll just need to have (or develop) tools to try a lot of options and see what looks the most compelling.

Still frames are probably not going to be that interesting -- the fun part about CAs is the predictable-yet-surprising motion, which can be either the usual visual form or converted to sound somehow.

A recent version of Golly ( https://golly.sourceforge.io ) added support for listening to evolving patterns -- see pop-sounds.py / pop-sounds.lua in the Scripts directory. That reduces patterns to a single dimension in an obvious way (just looking at population), ignoring a lot of the 2D complexity. No doubt there are a lot of other possible avenues to explore there.

Back in the day I read an article on HashLife in Dr Dobbs, which had a bit of an effect on me in terms of software architecture in terms of a set of new approaches, tightly coupled, providing astounding results.

Are there other interesting and unexpected algorithms in implementations of GoL?

The relatively-big, relatively-new thing at the moment is the application of SAT solvers to CGoL problems. Donald Knuth got the ball rolling on this, but we're still in the very early days of seeing what is possible with SAT solvers.

Every now and then a lucky or inspired SAT solver problem setup will throw out an answer to a really difficult-looking problem, with no apparent effort. But then that tends to tempt people into setting up more difficult problems to solve... and of course it's still very easy to set up problems that cover such a large search space that the search would take billions of years to complete on a planet-sized supercomputer.

So it's still very much an art form, rather than an exact science, to figure out what searches to try next.

Did the Game of Life change anything in your world view? Your belief in god, or how you view society and societal changes? Even if the change is not rigorous or logical but something anecdotal that nonetheless changed your emotions, I'd be glad to hear about it.

There have been a lot of "wow" moments in my Life career, watching complexity emerge out of the repeated application of simple rules -- but I guess I'd say that it was more a confirmation of things that I thought I knew already.

In 2001 I had already been playing around with things like the Mandelbrot set and aperiodic tilings and Douglas Hofstadter's strange loops for quite a few years, so I knew the kinds of magical things that the iterative application of simple rules could produce.

Where would you direct someone for tips on implementing Game of Life?

These days, without knowing more about preferred programming language or the purpose of the implementation, I'd probably start by pointing to this very thorough series of blog posts by Eric Lippert, from LifeWiki/Tutorials:

  https://conwaylife.com/wiki/Tutorials/Coding_Life_simulators

Life simulators have been coded in so many different ways, in so many languages, by so many different people in the last half-century ... that it takes several dozen articles to work through a reasonable survey of the possible ideas and methods.

Thank you!

I made a small solar powered CGOL(https://davidhampgonsalves.com/solar-powered-conways-game-of...) that has a low pixel count. After 100 frames it randomly generates a new starting point b/c I didn't implement loop detection.

Are their any algorithms or techniques for generating interesting starting states?

Have you dug a bit in the concept under wolframphysics.org? Discretization of PDE equations is interesting and some generating-functionology/combinatorics can be spotted more or less over there. CAs can enter anything under the computational umbrella, question being how sleekly. Have they achieved something already, do you share their interests? (you said "ama")

Ha, well, I've mostly successfully dodged the various Wolfram-science questions so far. I just finished reading a book on cosmology -- VSL theory -- but honestly a lot this kind of thing seems to be way too far above my personal abstraction ceiling. I can't tell whether some of these ideas really even mean anything at all, or if it's just somebody who is better at waving words around than I am.

This is wandering off of the Wolfram physics project a fair distance, but it's hard to see how space could be quantized in a Fredkin "Nature is finite and digital" kind of way, without the underling "grain" of the universe becoming obvious in some kind of experiment, and/or without causing deep contradictions in various experimentally well-supported relativistic effects that require that there isn't any such thing as a unique fixed frame of reference.

But quite possibly that's just a failure of imagination on my part, not anything wrong with the actual theories in question -- I'm probably complaining about some apparent implausibility two levels above or below where the information is actually flowing. And there are certainly all kinds of properties of our physical universe that are quantized in one way or another, for utterly mysterious reasons.

Long story short, there is certainly still room for some big surprises in theoretical physics, and I'm not about to claim that I'm clever enough to rule out any of these wild options.

I'm super interested in cellular automata.

One thing that particular piques my interest is the diversity of possible automata, not just forms in any particular one, but diversity of rule sets as well.

What do you think is special about the GOL rule set compared to other life-like rules?

Do you think it was a historical accident this particular rule set became so famous, or not?

Are there alternatives you are also interested in?

It was _kind of_ a historical accident, in the sense that if we ran history over again, it wouldn't be too surprising to see an alternate-history "Conway's Life" with a rule like "B36/S23" (HighLife) instead of "B3/S23". (Conway did really like the replicator and bomber and a few other fun things that HighLife has that Life doesn't.)

On the other hand, Conway had some very specific criteria for the rule he was looking for. "B3/S23" is about as simple a set of rules as you can find for a range-1 Moore-neighborhood outer totalistic cellular automaton on a square grid.

So unless Conway's eye had happened to get caught by some slightly more complicated rule before he and his team happened on B3/S23, he'd be quite likely to settle on "B3/S23" all over again. It's one of the few candidates for the simplest rule that does obviously interesting things and seems likely to allow for computational universality. I mean, there are untold numbers of equally promising rules in larger rulespaces like the "isotropic non-totalistic" rules

  https://conwaylife.com/wiki/Isotropic_non-totalistic_rule

... but most of those have rulestrings like "B2ci3ai4c8/S02ae3eijkq4iz5ar6i7e": it's just not anywhere near as simple to describe the rules, as it is for Life.

---------------

If we meet up with an alien civilization some day, it would be extremely amusing if we happened to show them some Life patterns and they said (in so many words) "Hey! You know about Pnurflpeef's Game of Life?!?" Not a likely scenario, by any means, but not quite impossible either.

Maybe this question is too low-concept, but what is your opinion of the glider as a Hacker symbol?

Er- I just viewed your book, clearly you think it's relevant and appropriate!

Do you have any particular thoughts about the glider as a Hacker symbol?

Heh, I'm not actually sure whether Nathaniel meant to invoke Eric Raymond's hacker emblem on the book cover or not. The grid is there, and the glider orientation is right, but the cells are squares and not circles. That orientation of the glider is kinda canonical, independent of the hacker emblem -- e.g., it's the phase that shows up in the "glider" LifeWiki article.

I emailed back and forth a little bit with Eric Raymond when the hacker-emblem proposal first came out, but I don't remember that I had anything very interesting to say. Mostly I was hoping to get the Life Lexicon factoid about the unix oscillator into the "Anticipations" section on the official Hacker Emblem page --

Unix: ... The name derives from the fact that it was for some time the mascot of the Unix lab of the mathematics faculty at the University of Waterloo.

Do you subconsciously see gliders and other patterns in your day to day life? In your dreams?

If a glider shows up somewhere by accident, like in an an otherwise random-looking arrangement of floor or wall tiles in a bathroom or somewhere, then I'll certainly pick it out immediately (and be unwarrantedly cheerful for the next half hour or so). But that doesn't happen all that often.

It seems like I rarely have dreams about Life patterns, though it does happen. Maybe some people with better-resolution imaginations might have a different experience, but Life patterns need a lot of precision and focus, and in my dreams everything is always fluid and shifting and I can never find my car keys or my homework, let alone any interesting Life configurations.

This post was funny to read thinking OP was referring to the old "Game of Life" board game.

https://en.m.wikipedia.org/wiki/The_Game_of_Life

This is not a question about GoL directly but more generally about CA. Do you have a sense for what the probability of a random CA is to be TME? Do you have any idea of how to automate the process, if not in general, then at least for a class of CA?

This is a very good question, but I'm not sure I can give a very good answer.

I'm not sure the "probability" part of the question is even well-defined, let alone answerable, unless you state a specific rulespace -- two-state range-1 Moore-neighborhood CAs on a square lattice, or three-state range-2 isotropic CAs on a hexagonal lattice, or what have you.

Basically, you just have to be able to demonstrate a working universal logic gate (a NAND gate or a NOR gate) in a candidate rule, and you've pretty much got Turing-machine equivalence.

The problem is, a lot more rules are computationally universal than you'd think when you first look at them. This is because it's often possible to get a candidate rule to act like a completely different rule, by filling the universe with something other than empty space.

So you can't just try out a few random-soup patterns, dash off a quick proof that "this rule necessarily explodes uncontrollably in all directions, so it's impossible for any circuitry to survive" or anything along those lines. What if you start with a universe of all ON cells, or a checkerboard of ON and OFF?

There are lots of rules where signals can propagate beautifully through that kind of non-empty medium, and occasionally some kind of Turing-complete mechanism might be found there, along the lines of what Matthew Cook did with Rule 110. So you really have to look at a lot of options before you can say for sure that a rule does not support universal computation -- and so far, it seems like a very tricky problem to automate the process of looking.

I would like to see a setup which is going to spawn as much dots as possible, I mean something like a gun but having as little static elements as possible while creating as much gliders as possible.

The "spawn as much dots as possible" sounds like a spacefiller:

  https://conwaylife.com/wiki/Spacefiller

But that's maybe a little too static for the "creating as much gliders as possible" part. You might like the glider-gun version of "Jason's p156":

  https://conwaylife.com/wiki/Period-156_glider_gun

Or ... this last year or two have seen an impressive number of new glider-gun discoveries, where a very active small "engine" produces a dense stream of gliders:

https://conwaylife.com/wiki/Period-24_glider_gun#Other_perio... https://conwaylife.com/wiki/Period-25_glider_gun https://conwaylife.com/wiki/Period-48_glider_gun https://conwaylife.com/wiki/Period-15_glider_gun https://conwaylife.com/wiki/Period-16_glider_gun

Thank you for perfect answers! Seems like a binary symmetry plays some role in this game because both configs are so. And I am amazed that Period-156 has a quadro symmetry!!! (at least if I refuse to consider it as a static image).

Are there any configs (I mean, those having any interesting behaviour) with intention having more than 4 symmetry parts? Or at least just more quadro symmetry configs? I am absolutely sure (since today) there are some for any 2^n, just all unfound.

Any attemts to create Conway's life on hexagon map with apropriate rules?

upd: for a single stream of gliders, what config gives as many gliders per 100 generations as possible? No matter what else it does, I just want a line of gliders with as little space as possible.

-- It's interesting to look at the different symmetries on Catagolue, where the idea is to generate a lot of random soups with different symmetry types, and then just run those patterns and see what comes out. The D8_1 and D8_4 symmetries are 8-way symmetric, which is as high as you're going to be able to get on a square grid.

  https://catagolue.hatsya.com/census/b3s23/D8_1
  https://catagolue.hatsya.com/census/b3s23/D8_4

Scroll down to the bottom of those pages and click on, especially, some of the higher-period "xq{N}" categories. These are objects that showed up "naturally", evolving from random soups.

-- There have definitely been a number of people over the years exploring various outer-totalistic rules on a hex grid, and (to a lesser extent) isotropic non-totalistic rules: see

  https://conwaylife.com/wiki/Hexagonal_neighbourhood

-- The smallest period at which gliders can follow one another is period 14. We don't have a true period-14 gun yet, though. The closest we have is a "pseudo-period" gun -- actually period 28, but it generates two gliders per period, so you end up with a period-14 stream:

  https://catagolue.hatsya.com/object/gun_14/b3s23

Not a serious question, but what should I improve to make my g.o.l. background cooler @ https://www.franzai.com/ ?

That background seems pretty cool as it is -- I like the changing colors. Maybe try playing with depth as well, along the lines of the T=450 point of the LifeViewer demo pattern here

  https://conwaylife.com/wiki/LifeViewer

-- or go for broke and steal some code from

  https://oimo.io/works/life/

for an infinite zoom into (or out of) a fractal Life pattern.

What do you think about other forms of cellular automata?

I came across excitable media recently and found it fascinating.

Do you have any other examples of cellular automata you found interesting or worth pursuing?

If you do a second edition, I would love a chapter on Life implementations, particularly how to implement a Life simulator that can execute these enormous patterns efficiently.

There's definitely plenty of material for a Volume II book (and several volumes after that, for that matter). At the moment, though, Nathaniel and I think that it might be somebody else's turn to write those!

  https://conwaylife.com/forums/viewtopic.php?p=136037#p136037

Definitely check out this blog series by Eric Lippert in the meantime, though:

  https://conwaylife.com/wiki/Tutorials/Coding_Life_simulators

Could the Game of Life run Doom, since it's Turing-complete ? I remember seeing an excerpt of a video where you could run the Goal inside the GoL.

Yes, you'd just need to have a way to provide input (probably easiest as a demo file), and a machine big enough to simulate the pattern. You'd definitely be waiting for a while to see any action, though :P

I e always wondered are there setups in GOL that seem to go on forever with new patterns or does everything ready a static or repeating state?

Some can be constructed with varying levels of success. Default Golly comes with an “infinite novelty” scenario; it’s worth checking out for a couple hours.

Yup, it doesn't take a very big starting pattern to produce likely infinite novelty -- though it's not always easy to prove that any given pattern won't eventually unexpectedly "go boring" due to some kind of unexpected feedback effect.

Life being Turing complete, it's also not difficult to build a pattern with an unknown fate -- like a Fermat-prime calculator that will stop growing if it ever finds a sixth Fermat prime, or the Collatz-sequence simulator described here:

https://conwaylife.com/wiki/Fate#Unknown_fate

You would like subleq/muxleq languages them.

What are the best ways to keep up with GOL developments?

Links you posted and hobbyist forums, formal research papers, or something else?

We've tried a lot of different methods over time. Currently the LifeWiki --

  https://conwaylife.com/wiki/Main_Page

-- is the most likely central location; any sufficiently big news will probably find its way into the CurrentNews pane, sooner rather than later.

For a couple of years I've been trying to keep up with an informal summary of new developments, in an email-newsletter form mostly intended for "old-guard" Lifenthusiasts:

  https://conwaylife.com/forums/viewtopic.php?f=7&t=5650

As I mostly expected, it ends up being a bit too much work for one person to do properly. But the back issues there do go into a bit more detail than there is room for in LifeWiki CurrentNews back issues.

Did you ever meet or interact with Conway?

Not quite, unfortunately! I almost had the opportunity, briefly, in 2019 when I was contributing some patterns to a short film that Will Cavendish was working on with Conway, called "Thoughts on Life":

  https://www.thoughtsonlifefilm.com/

But there was never really a good excuse to arrange a meeting, given Conway's very fragile health at that point -- and then COVID came along.

Conway regularly attended the bi-annual Gatherings for Gardner in Atlanta for quite a while, but by the time I started attending he could no longer travel that far.

Not the author but I'd often seen him at the local coffee shop in Princeton reading or working. He was incredibly kind and generous with his time (I also made sure to not ask about GoL because I'd read about his feelings regarding it). He even showed my 6 year old a few puzzles. Even though we'd see him all the time, each time was like seeing a celebrity for me.

Given a torus what initial configuration yields the maximum number of unique generations? :)

What is in common between the bazillions of CGoL implemetations? Is convergance possible?

Have there been any interesting applications of fuzzy logic or neural nets for rules?

People have definitely tried this kind of thing, but so far -- from what I've seen -- Game of Life problems seem to be highly resistant to neural-net types of solutions.

Take spaceships, for example. You can train a neural net to recognize spaceships, but there aren't any reliably recognizable features that can distinguish a spaceship from a non-spaceship. To find out if a never-before-seen pattern is a spaceship with period N, you really have to run it for N ticks and see if you get the same pattern back again at an offset. Visual similarity with other spaceships just plain isn't relevant, unless the similarity is 100%; a pattern with a 99% match on a 100-cell spaceship will almost always be ... not a spaceship at all.

A good analogy for this might be training a neural net against images of prime numbers up to 997, printed in decimal in some standard font. Sure, you can train a neural net to recognize prime numbers less than 1000, with great accuracy ... but primality isn't a visual property of a printed number, it's something that you have to do some mathematical tests to find out about.

So if you try your trained neural net on prime numbers above 1000, you're going to be rather disappointed with its performance. CA spaceship recognition is the same kind of problem... possibly worse, since you could at least have some hope of a neural net correctly recognizing non-primes by their last digits.

What would an operating system look like built using conway’s game of life ?

Do you think asking a candidate to implement GOL in a 45 minute live coding exercise job interview and then expecting a fully working implementation if it’s clear they have never come across the problem before?

Devs I ask this come down 50:50 on if it’s reasonable or not.

What is the environment? What language and frameworks are you testing them on?

And what are these hypothetical candidates interviewing for, exactly?

In the '80s and '90s, every time I got a new computer, one of the first things I'd do is write a very simple CGoL simulator, and then sit back and marvel at how much faster it was than the previous PC was.

So personally I guess I would have aced that question, in any number of languages and platforms... and yet I'm not really a particularly good programmer. It took me quite a few new-computer cycles before I started wandering down the various optimization rabbit-holes --

  https://conwaylife.com/wiki/Tutorials/Coding_Life_simulators

-- and I never got anywhere near as far as either HashLife or QuickLife. Now I just happily use other people's nicely optimized code, for the most part.

So... it's a problem that a sufficiently nerdy programmer type of a certain age will be very likely to have encountered before, and you'd learn completely different things about a candidate depending on the level of that past experience.

many similar life simulations in more dimensions (3d,4d, etc) or with diferent shapes that are interesting at all? (im obviously thinking hexagonal or trianglar)

Do you see a role for generative AI to discover new patterns?

I don't want to say that there's no possible role for AI in Life research, but it's hard to see how something like ChatGPT can be helpful.

1) The placement of a single cell in a huge pattern will very often make the difference between a working Life pattern and something that catastrophically implodes. So making a generative AI like ChatGPT do any work on Conway's Life is very much like making it play chess: sooner rather than later, something really important will end up slightly out of place, and ChatGPT will have no way of knowing.

2) Unlike a lot of other subjects where ChatGPT really shines, Conway's Life is an incredibly niche subject. There simply isn't anywhere near enough training data for ChatGPT to give reliable results, even for fairly basic questions:

  https://conwaylife.com/forums/viewtopic.php?p=183306#p183306

3) However, there are definitely a number of areas of Life research where other types of AI might end up coming in very handy -- e.g., in monitoring and tuning parameters for very long-running and difficult searches. For this we need something much less like ChatGPT and more like Douglas Lenat's EURISKO, to try new experiments and learn what it can from the results ... EURISKO also happened to come up on Hacker News today:

  https://news.ycombinator.com/item?id=40128285

We just can't rely on generative AI to re-shuffle what is already known and make it into a nice new package, when what we're searching for is something that's never been seen before.

What has the Conway game of life done for mankind lately?

It's made a lot of Lifenthusiasts happy, and that's not nothing I suppose.

It has also taught a lot of people a little something about the likelihood of emergence of complex behavior from very simple iterated rules.

And maybe you could say that several of the larger collaborative Life projects that have happened recently have been very good examples of non-political international co-operation, in a world that these days seems like it could use a few reminders that such things are still possible.

What is something that you think the average HN user would find useful/surprising about Life? How could it apply to their daily lives?

Heh, I think I can find answers for "surprising" a lot more easily than for "useful". The main practical use for Conway's Life is as a teaching tool, giving a nice explorable example of layers upon layers of incredible complexity that can arise from very simple rules. So I suppose that people who can benefit from that kind of insight might find Conway's Life "useful", in a way -- engineers, mathematicians, and just anyone who is curious about the universe we live in and the physical laws that seem to underly its behavior.

The big surprise that I've been spending the most time on lately is the utterly strange result that if you can build something by colliding gliders together -- no matter now many gliders and no matter how big the final pattern is -- then you can also build it by starting with exactly fifteen gliders in an otherwise empty Life universe:

  https://biggieblog.com/building-arbitrary-life-patterns-in-15-gliders/

It's a mind-bending result -- partly just a mathematical trick, since you end up encoding a whole lot of information in the space between the gliders -- but it's just really amazing that all the details have actually been figured out to make the trick work, and that it's possible to simulate the whole process on a personal computer.

Thank you for sharing your curiosity with the world

Wolfram's "A New Kind of Science" posited the study of cellular automata as a revolutionary new field of science. Did you agree then? Do you now? If you changed you mind, why?

I've never had a good short answer to this kind of question. It's much more of a twenty-page essay question, with a lot of subtleties to dive into. I've tangentially crossed paths with Stephen Wolfram off and on for a bit over a decade now, starting with attending a Wolfram Summer School session --

  https://education.wolfram.com/summer-school/alumni/2011/

-- and every few years someone from Wolfram Research will show up for an email discussion about one interesting topic or another. I'm more of a "determined hobbyist" than a proper theorist along the lines of Ed Fredkin, though, so while I'll enthusiastically agree that _A New Kind of Science_ documents a whole lot of fascinating stuff... I might not be the best judge of whether it all adds up to something that should be called "revolutionary".

(I'm quite sure that I don't do anything "revolutionary" myself -- I just try to encourage Conway's Life research to continue. Discoveries have kept building on previous discoveries for fifty years now, and I'm just really curious to see what will happen next.)

He has since stated fixed geometry models are not sufficient and has moved on to graphs.

Ooh answer this one!

do you like rule 110 better than conways game?

Why you are so clever than 99.9999% of the world's population?

I'm not -- I'm just more of a Conway's Game of Life expert than 99.9999% of the world's population. But that's just due to experience and invested time, not cleverness.

Could probably add at least one more nine to the end of that number, and maybe two ... the CGOL community is very widely dispersed geographically but it's really very small. There just aren't very many Conway's Life Expert candidates out there! For me to hit 99.999999%, there would have to be fewer than eighty people out there who have more knowledge about Conway's Life than I do

At least for certain topics -- like the reverse caber tosser, for example --

  https://conwaylife.com/wiki/Reverse_caber-tosser

-- I'm fairly confident that I can list pretty much every person in the world who has a deep knowledge of the workings of 15-glider RCT universal construction ... and there are a lot less than eighty of them.

What is so special about the game of life? how does it differ from some simple game mechanics found in other videogames? The aim of this question is to understand what motivates and fuels passion for yourself and people in your community

Your question also demonstrates that you've not done any effort at all to find out what game of life is.

Have you read Alien Information Theory: Psychedelic Drug Technologies and the Cosmic Game by Andrew R. Gallimore [0], and do you have any thoughts on his cosmology vis a vis cellular automata? And perhaps also the same question related to Stephen Wolfram's physics project?

[0]: https://www.amazon.com/Alien-Information-Theory-Psychedelic-...

Shouldn't this be a "Ask HN" or something similar? Also, let's not make AMAs a thing on HN. Better to post an interesting link and then engage with people in the comments.

I did a bit of homework before posting this, and there were just enough Hacker News hits on "AMA" (from Sam Altman, Peter Roberts, etc.) that it didn't look like there would be any harm in trying this experiment.

I could certainly try an "Ask HN" at some point, but haven't been able to think exactly what question I would ask. "How many people know what a reverse caber tosser is?" is one that I'm curious about, but I suspect I'd get mostly just crickets. Really I wanted other people to ask questions... and I'm having lots of fun with the results so far!

it didn't look like there would be any harm in trying this experiment

There isn't any harm, if anything, more experts, accidental or otherwise, should do this.

There is harm, yes. Regularly hosting AMAs will turn this website into a social platform like reddit. Regular discussion will die down as personalities take over. It's the quick road to decline. The internet isn't what it used to be, public forums need to be guarded from the influx of low-quality commenters that consider everything a social platform first and throw regular, on-topic discussion out of the window. In time, low-quality and high-quality commenters form two groups and when they interact, the high-quality commenters leave.

The site is a social platform as it is and AMAs by knowledgable people that fit the forum are totally fine on HN. 'HN is turning (or is going to turn) into reddit' is trope as old as the site. This post and its thread were of higher quality than most HN threads so if something is going to ruin HN, it's not going to be this AMA.

I took a day off of work yesterday to try this AMA idea out, and I'm thinking it turned out pretty well all in all. It was definitely a one-time experiment, though, not something I'll do again.

Something just occurred to me from a review of recent HN item titles: maybe what I _will_ try sometime is a "Show HN" post, for some shiny new Life discovery that seems particularly interesting.

Show HN is pretty specific and has its own weird rules (linked in the show tab up top). It’s mostly for things people have made that can be tried out. You should definitely post interesting things you’ve found, if they don’t fit Show HN, you can just skip the Show HN prefix and avoid the bureaucracy.

Thanks, that's a big help! I think actually the Conway's Life community does quite regularly have "interesting things" that could fit the Show HN model.

The example I'm thinking most about is the fixed-cost 15-glider construction for absolutely anything that's glider-constructible at all --

for which we do have some eminently runnable code that showcases the entire process of 15-glider construction from beginning to end, with subtitles ...

  https://conwaylife.com/forums/viewtopic.php?p=153609#p153609

... running inside Golly, but that's a free download, and the Lua script version doesn't need any extra Python installation or configuration or anything.

So if I don't get too much "Nah don't do that" feedback here, I might try putting up a Show HN post for the new super-optimized RCT15 project, once the last pieces of that get completed.

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