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Particle Life

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Re: Particle Life

#61

Post by itishappy »

at_a_remove wrote: post #10
billytetrud wrote: post #2

This is fascinating. It's like a more complex game of life than John connoway's. It's crazy that little creatures seem to form at such small scales easily with these parameters. It's almost like the parameters of our real universe intentionally made it difficult to form life, rather than easy as some people seem to think.

They are less creatures than molecules. Now, mind you, as some complex sets of rules approach steady state I can pretend they are far-flung stellar empires with colors ascribed to each type of system of government (and have). What is fooling you is the motion. This is sustained because the system has no conservation principles built in. You can make A-B pairs where B is attracted to A, A is repelled by B, and off the…

> I would like to see this in three dimensions...

Oh, there's one of those too! I don't see ways to change the falloff though, just the magnitude...

https://hunar4321.github.io/particle-life/particle_life_3d.h...

Re: Particle Life

#62

Post by lebean »

geraldwhen wrote: post #23
billytetrud wrote: post #13

Earlier quoted context omitted.

There are, in fact, reasons to believe that. Nothing definitive of course. But the fact that we haven't been absorbed by a von neumann swarm or something like it places strict limits on the prevalence of life and/or what stages that life can achieve. One would either have to belive that intelligent life is vastly less likely than non-intelligent life, or that life itself is quite rare, or that life simply hasn't been…

There is no evidence that space travel is practical or sustainable. The only viable spaceship known to man is Earth, and we don’t steer it. Maybe there are lots of earth-like planets with intelligent beings, but travel is impossible and communication is useless given the time delay.

Turns out that the great filter was something as mundane as interstellar travel being impractical.

Re: Particle Life

#63

Post by franky47 »

One of my first coding projects at school was Conway's game of life, but I found the black and white a bit too boring so I pushed the assignment further by introducing RGB "genes", and give spawns a combination of their parents' colours (with random mutations).

It's very fun watching which "faction" might take over the board.

Demo: https://genetic-life.surge.sh/

Source (ported from the original C++ into Rust/WASM): https://github.com/franky47/genetic-life

Re: Particle Life

#65

Post by noduerme »

wetmore wrote: post #59
noduerme wrote: post #53

Earlier quoted context omitted.

This already does look like it has falloff... mutual attractors clearly seem more attracted to nearby particles than to larger groups further away.

I assume it falls off at inverse of r squared, which is why the person you're replying to is mentioning other functions besides that one.

I read them differently.

>> I have a feeling that such a system would grind to a halt even with clever optimizations.

I took this to mean that they thought there was no falloff calculated at all. If there is, I don't see why substituting a different function, e.g. cube vs square, would be significantly more CPU-intensive.

Re: Particle Life

#66

Post by petters »

billytetrud wrote: post #18
UncleOxidant wrote: post #16

Earlier quoted context omitted.

> One would either have to belive that intelligent life is vastly less likely than non-intelligent life That seems like a valid belief. Getting to a technological stage such that a species would be detectable over the vast distances of space could indeed be quite rare. You have to also consider the temporal aspect: intelligent, technologically advanced species may have evolved several times but gone extinct before we…

> That seems like a valid belief. Its not at all clear in general. It might be true. But it also might not. It seems quite reasonable to believe that life inevitably evolves into intelligent life if given enough time. Why some life would and some life wouldn't isn't at all clear. > advanced species may have evolved several times but gone extinct before we could notice them. All the potential answers to the Fermi Para…

> It seems quite reasonable to believe that life inevitably evolves into intelligent life if given enough time.

From what we have seen on Earth, it does not seem inevitable. Dinosaurs were the largest land animals for a very long time and they did not, as far as we know, evolve towards being more intelligent. The same seems to be true for many other animal groups that have been around for a long time.

Re: Particle Life

#67

Post by thanhhaimai »

pbowyer wrote: post #34

This is the most interesting one I generated: https://hunar4321.github.io/particle-life/particle_life.html... It eventually settles down to one large and unstable blob and another stable. Neither move so that's it. But before that it did what I had expected to see with objects meeting and merging

Tagging along: https://hunar4321.github.io/particle-life/particle_life.html...

This one is really fun for me. It has a lot of actions and good shapes.

Re: Particle Life

#68

Post by at_a_remove »

noduerme wrote: post #65
wetmore wrote: post #59

Earlier quoted context omitted.

I assume it falls off at inverse of r squared, which is why the person you're replying to is mentioning other functions besides that one.

I read them differently. >> I have a feeling that such a system would grind to a halt even with clever optimizations. I took this to mean that they thought there was no falloff calculated at all. If there is, I don't see why substituting a different function, e.g. cube vs square, would be significantly more CPU-intensive.

You focused on just one clause. Consider the whole:

1) Three dimensions, not two. Therefore distance is not the square root of (delta-x * delta-x + delta-y * delta-y) but the cube root of (delta-x * delta-x + delta-y * delta-y + delta-z * delta-z). More operations.

2) Three dimensions, not two. As you start increasing the number of dimensions, the simulation feels more and more empty. One hundred particles on a line a thousand units long is crowded. One hundred particles on a grid of one thousand by one thousand feels like more "room" for that same number of particles. In a volume of a thousand by a thousand by a thousand, one hundred particles feels too few, and one would naturally increase the number of particles. Naively, which is to say without optimizations, the number of force computed grow as N-squared. More operations.

3) Cube falloff goes by r * r * r, rather than r * r. More operations, by fifty percent. And I did suggest some more exotic functions in there which certainly could be more daunting.

Re: Particle Life

#69

Post by MagicMoonlight »

Even with such a basic system you immediately start to get self-organising little bubbles of life. If something had a way to replicate in these bubbles, you would have the first cell.

Re: Particle Life

#70

Post by MagicMoonlight »

Buttons840 wrote: post #42
beders wrote: post #12

It is amazing how easily self-sustaining structures emerge from such simple rules. Mesmerizing.

Is there any "sustaining" in the simulation? Is death a possibility? If not, then there is no "sustaining".

There was no death for the original life.

Rotting is caused by living organisms. Being eaten is caused by living organisms. Disease is caused by living organisms.

They could not die until death evolved. They could be physically destroyed but that’s not that likely.

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