Thread for basic non-CGOL questions

[wildmyron]

Is there a pattern other than the dot, domino or other symmetric patterns that can't be a spaceship in any non-totalistic rule?

Presuming that your question is about isotropic non-totalistic rules, then calcyman answered this question conclusively, and in the affirmative, here. There was some further discussion around the topic (restricted to isotropic rules without B0) in that thread as well.

Any pattern can be a spaceship in some non-isotropic rules, which are non-totalistic.

I'm pretty sure gameoflifemaniac is referring to isotropic, non-totalistic rules, where the dot and domino cannot be a spaceship.

Any pattern can be a spaceship in some non-isotropic rules, which are non-totalistic.

Not sure about that. What about this:

Code: Select all

x = 93, y = 81, rule = B/S01234678
76bo$76bo55$o24$91b2o!

That pattern is certainly a spaceship in some non-isotropic, non-totalistic rule - so it doesn't serve as a counter example to muzik's statement. Even if you restrict consideration to isotropic rules, I don't think you can simply rule out that it might be a spaceship in some rule. For example, here is a pattern made of two isolated dominos which is a spaceship in an isotropic rule with B0:

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x = 5, y = 5, rule = B02c3e6e/S1e
4bo$4bo3$2o!

It seems it would be extremely unlikely for the two domino + dot pattern to be a spaceship in some isotropic rule, but I don't think you can rule it out without a proof or actually testing a large majority of the B0 rules which support spaceships (some of them you'd be able to rule out without testing explicitly, I'm sure).

By the way, Thank you to the people who contributed to discussion of this topic in the other thread (who hopefully read this thread too!), and apologies for not participating in the discussion. I've still got lots of thoughts about this which I'm trying to straighten out in my head.

Edit:
Here's another example with larger spacing:

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x = 6, y = 6, rule = B02c3ry4qtwz6e/S02an4r5r6n
5bo$5bo4$2o!

And another without the diagonal symmetry:

Code: Select all

x = 5, y = 6, rule = B01e2-a3j4ay5ac6ai8/S1c4k
4bo$4bo4$2o!

[wildmyron]

Has anybody tried to make a WLS/Gfind/Zfind-ish spaceship search program for LTL rules?

I believe the answer to that is no. I think that for a gfind/zfind style program the larger neighbourhood will make the program a lot more complicated. I imagine that range 2 is probably manageable, but I say that with no experience of designing this kind of program.

[muzik]

What is the name for the fractal this generates?

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x = 1, y = 1, rule = B13/S024V
o!

[muzik]

What's the MAP sting for this rule?: viewtopic.php?f=11&t=2030&p=31810&hilit ... iod#p31810

[Rhombic]

Is there a limit for the highest possible period spaceship such that all phases have the same population?
If so, what is it. Otherwise, what is the highest period spaceship that fulfils this description that has been discovered?

[muzik]

Are there any known 1D replicators where the central replicator stays alive after every replication cycle, resembling a one-dimensional version of the Fredkin rule and simulating Wolfram rule 150?

Seems like the fits the description:

Code: Select all

x = 3, y = 1, rule = B02aci6i/S1e5i
3o!

Anyone willing to make a "Sierpinski generator" equivalent in rules where this works?

[muzik]

Are (1,1)c/2 diagonal spaceships with 3 cells possible in range-1 2-state isotropic rules without B0?

And on that subject, (2,2)c/4?

[gameoflifemaniac]

Is the number of possible non-totalistic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?

[BlinkerSpawn]

Are (1,1)c/2 diagonal spaceships with 3 cells possible in range-1 2-state isotropic rules without B0?

And on that subject, (2,2)c/4?

I think this is the smallest possible (1,1)c/2 ship:

Code: Select all

x = 3, y = 3, rule = B1e2c3a5k6c/S01e4i
obo$o$b2o!

[muzik]

Are (1,1)c/2 diagonal spaceships with 3 cells possible in range-1 2-state isotropic rules without B0?

And on that subject, (2,2)c/4?

I think this is the smallest possible (1,1)c/2 ship:

Code: Select all

x = 3, y = 3, rule = B1e2c3a5k6c/S01e4i
obo$o$b2o!

...which can be easily be disproved by the example from the 5s project:

Code: Select all

x = 3, y = 4, rule = B2ac/S1
2bo2$b2o$o!

[praosylen]

Are (1,1)c/2 diagonal spaceships with 3 cells possible in range-1 2-state isotropic rules without B0?

And on that subject, (2,2)c/4?

I think this is the smallest possible (1,1)c/2 ship:

Code: Select all

x = 3, y = 3, rule = B1e2c3a5k6c/S01e4i
obo$o$b2o!

If you're measuring by bounding box, yes. If you're measuring by population, then no, 4-cell ones are possible:

Code: Select all

x = 4, y = 3, rule = B2-e/S1
3bo$2bo$obo!

I have a mental outline of a proof that 3-cell c/2 diagonal ships of any period are impossible, but I don't know that I'll get around to finishing it and posting it — in any case, there are probably many ways of tackling the problem, so nobody should let me stop them from trying.

[Rhombic]

growing spaceship, moving wick-stretcher?

Code: Select all

x = 16, y = 35, rule = B2ein3acir4einqtyz5aq6ain7e/S1c2-an3iqry4n5inqry6kn7e8
13b3o$13bobo2$11bo$12bo$11b2o$10bobo$11bo$10b2o$9bobo$10bo$9b2o$8bobo$
9bo$8b2o$7bobo$8bo$7b2o$6bobo$7bo$6b2o$5bobo$6bo$5b2o$4bobo$5bo$4b2o$
3bobo$4bo$3b2o$2bobo$3bo$b3o$ob2o$3o!

[gameoflifemaniac]

Is the number of possible non-totalistic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?

[wildmyron]

Is the number of possible non-totalistic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?

No. Hensel notation is used to specify isotropic rules only. The wiki page on Non-totalistic_Life-like_cellular_automaton is confusing on that point because it seems to have started out as a description of the isotropic rulespace and then morphed into a broader description of non-totalistic CA. It also seems wrong to me to describe anything non-totalistic as "Life like" - see Cellular_automata#Life-like_cellular_automata for the definition.

[gameoflifemaniac]

Is the number of possible non-totalistic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?

Oops... I meant 'Is the number of possible isotropic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?'

[wildmyron]

Is the number of possible non-totalistic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?

Oops... I meant 'Is the number of possible isotropic rules equal to the number of non-totalistic rules writable using Alan Hensels notation?'

Yes

[Macbi]

Only assuming you're using the "canonical form".

Also, it's a bit weird to ask if there are the same number. It's more important to know that each of them is expressed exactly once (which is also true).

[gameoflifemaniac]

Is this spaceship known?

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x = 4, y = 5, rule = B34/S34
4o$3bo$o2bo$b3o$bo!

[BlinkerSpawn]

Is this spaceship known?

Code: Select all

x = 4, y = 5, rule = B34/S34
4o$3bo$o2bo$b3o$bo!

It's the second pattern under "c/3 orthogonal spaceships" in Niemiec's collection for 3/4 Life, known no later than 19 Feb 2015.

[muzik]

Can this be a tagalong for any spaceships in Life-related rules?

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x = 4, y = 4, rule = B3/S23
2b2o$b3o2$o!

[Bullet51]

Can this be a tagalong for any spaceships in Life-related rules?

Code: Select all

x = 4, y = 4, rule = B3/S23
2b2o$b3o2$o!

Yes.

Code: Select all

x = 24, y = 29, rule = b357s238history
18.A$5.A6.2C3.A.A$4.A.A4.3C2.5A$2.A5.A7.2A.2A$A2.5A2.C6.A.A2$13.3A5.
3A$3A5.3A2.3A5.3A2$3.A3.A$.A3.A3.A$A9.A4.2A.A.2A$15.A5.A$A2.A3.A2.A4.
2A3.2A$.A.2A.2A.A3.11A$.2A.3A.2A$A2.2A.2A2.A2.2A3.A3.2A$5.A10.A3.A$A
2.A3.A2.A2.2A.A3.A.2A$.2A5.2A4.2A.A.A.2A$3.2A.2A7.A5.A$3.A.A.A7.A.3A.
A$3.5A9.3A$.A.A.A.A.A7.A.A$4.3A9.A.A.A$3.5A7.A.3A.A$.9A5.A5.A$15.A5.A
$17.3A!

[lifeisawesome]

Can this be turned into [s]an oblique spaceship[/s] a c/3 diagonal spaceship?

Code: Select all

x = 3, y = 3, rule = B3/S23
obo$obo$b2o!

Edit: Dang, I wish the forums had a [s] tag.

[gameoflifemaniac]

Can this be turned into [s]an oblique spaceship[/s] a c/3 diagonal spaceship?

Code: Select all

x = 3, y = 3, rule = B3/S23
obo$obo$b2o!

Edit: Dang, I wish the forums had a [s] tag.

No. It is proven that in B3/S23 no diagonal ships faster than c/4 exist.

[muzik]

It could be, if you can come up with a program that runs range-2 von Neumann non-isotropic rules, preferably with an acceptable notation.

[lifeisawesome]

Is this a billiard table?

Code: Select all

x = 9, y = 9, rule = B2ei3e/S
bobobobo$o7bo2$o7bo2$o7bo2$o7bo$bobobobo!