Thread for basic questions

[falsifian]

How does Catagolue-style soup searching decide what a distinct pattern is? I noticed that this double block pattern doesn't appear in any census, even though I've manually found it a few times just simulating soups for fun with Golly.

Why isn't it in the census? Is that pattern considered to be two separate blocks? Am I wrong in thinking it's not in the census? (I don't see anything under "sample occurrences".) Am I misunderstanding something else? The last explanation I can think of is this: the soup I simulated was big, maybe 1000x1000, so I can't rule out the possibility that the double block pattern arises often in big soups but not often from small soups. Does that seem at all likely?

(I think also observed a quad block once too, and that similarly doesn't have any sample occurrences. In that case, the Catagolue object page even has a comment.)

[wwei23]

Because apgsearch separates it into two blocks.

[77topaz]

Why isn't it in the census?

Because that's a pseudo still life, and Catagolue doesn't include those in its censuses (par a few bugs), only strict still lifes.

[falsifian]

Because that's a pseudo still life, and Catagolue doesn't include those in its censuses (par a few bugs), only strict still lifes.

Thanks; the term "pseudo still life" was useful. I took a look at the wiki page on pseudo still-life, and it talked about "non-interacting" patterns. Am I correct in guessing two patterns are "non-interacting" if after deleting either one, the other would still evolve the same way? Sorry if it's defined somewhere; I did just some cursory searches and didn't find the definition in an obvious place.

(One thing I notice about these two blocks: they are close enough to each other that, for example, if I turned off a cell in one of the blocks on the side that's close to the other block, the space in between would fill up in a way that would not if the other block were not present. Maybe what I'm observing is that you can't just construct a pseudo still life willy-nilly out of any pieces arranged however you like, so it's still a bit interesting to see which ones are possible.)

[wildmyron]

I took a look at the wiki page on pseudo still-life, and it talked about "non-interacting" patterns. Am I correct in guessing two patterns are "non-interacting" if after deleting either one, the other would still evolve the same way? Sorry if it's defined somewhere; I did just some cursory searches and didn't find the definition in an obvious place.

Non-interacting in this context just means that you can separate the sub-patterns and nothing will change as a result. I don't think the term is used here with any strict definition in mind. Keep in mind the pseudo still lifes mentioned on the wiki which can only be partitioned into a minimum of three (or more) sub patterns. This means that if you remove just one strict still life from the object the remainder will not be stable - it too needs to be divided for the constituent parts to remain stable. The Life Lexicon entry has an alternative wording:

:pseudo still life A stable pattern whose live cells are either immediately adjacent to each other, or are connected into a single group by adjacent dead cells where birth is suppressed by overpopulation.

As stated, this includes strict still lifes in the definition, but they are generally excluded from consideration.

There is some discussion of this topic in the thread Enumerating Still Lifes (in C). This post in particular is relevant to your enquiry.

As to why Catagolue separates pseudo still lifes rather than including them in the census, that's a decision made by calcyman which I'm sure he's elucidated somewhere on the forum, but I can't recall where he may have done so.

[Majestas32]

Because that's a pseudo still life, and Catagolue doesn't include those in its censuses (par a few bugs), only strict still lifes.

Thanks; the term "pseudo still life" was useful. I took a look at the wiki page on pseudo still-life, and it talked about "non-interacting" patterns. Am I correct in guessing two patterns are "non-interacting" if after deleting either one, the other would still evolve the same way? Sorry if it's defined somewhere; I did just some cursory searches and didn't find the definition in an obvious place.

(One thing I notice about these two blocks: they are close enough to each other that, for example, if I turned off a cell in one of the blocks on the side that's close to the other block, the space in between would fill up in a way that would not if the other block were not present. Maybe what I'm observing is that you can't just construct a pseudo still life willy-nilly out of any pieces arranged however you like, so it's still a bit interesting to see which ones are possible.)

Essentially a pseudo still life is a still life that can be partitioned into 2, 3, or 4 pieces, each of which are individual still lives.

(By the way, the "quad block" comment was me. I think?)

[falsifian]

Thanks for the detailed explanation, wildmyron.

[AforAmpere]

Is it theoretically possible to make this into a growing spaceship, with some kind of one-time use reflector and puffer?

Code: Select all

x = 477, y = 271, rule = B3/S23
476bo$474b2o$475b2o62$obo$b2o$bo61$347bo$345b2o$346b2o45$314b2o$315b2o
$314bo15$129bobo$130b2o$130bo46$162bo$161b2o$161bobo13$218bo$216b2o$
217b2o9$209b2o$208bo2bo$208bo3bo$209bo2bo$209bo2bo$210b2o!

It moves forward at 2c/516, which is the problem.

[dvgrn]

Is it theoretically possible to make this into a growing spaceship, with some kind of one-time use reflector and puffer?... It moves forward at 2c/516, which is the problem.

Theoretically possible, sure. It's not immediately clear to me how to use those output gliders to trigger the next input glider, but it seems as if that should be possible somehow. Failing that, we could just puff lines of junk to catch the gliders and get rid of them:

Code: Select all

x = 1251, y = 652, rule = B3/S23
1250bo$1248b2o$1249b2o62$obo$b2o$bo61$1121bo$1119b2o$1120b2o62$129bobo
$130b2o$130bo61$992bo$990b2o$991b2o62$258bobo$259b2o$259bo61$863bo$
861b2o$862b2o62$387bobo$388b2o$388bo61$734bo$732b2o$733b2o62$516bobo$
517b2o$517bo48$538b2o$538b2o2$642b2o$641bo2bo$547b2o93b2o$547b2o2$538b
2o95b2o$538b2o94bo2bo4b2o$635b2o4bo2bo$642b2o2$547b2o56bo22b2o$547b2o
54b2o22bo2bo4b2o$604b2o22b2o4bo2bo$635b2o3$628b2o$627bo2bo$628b2o3$
596b2o$595bo2bo$595bo3bo$596bo2bo$596bo2bo$597b2o!

It should also be possible to puff a wick of one-time turners that produces exactly the required gliders to support that reaction. Might not be exactly trivial, because the input gliders' lanes overlap... maybe four or five identical OTT wicks on each side, each contributing 1/N of the required gliders?

I don't suppose it will work to replace those gliders with still lifes, again because of the overlap problem. Have you tried compiling a Caterloopillar with that speed, that can be modified into a Caterloopillarake?

It doesn't seem too likely that multiple copies of this could be combined usefully to make a self-supporting macrospaceship, but I suppose stranger things have happened in Life.

[KittyTac]

Is a period halver possible?

[dvgrn]

Is a period halver possible?

Yes! Sort of. There's (currently) no such thing as a generalized period halver, where you just drop a simple mechanism onto a signal lane and it cuts the period in half no matter what it is. There will have to be a little adjustment, at least, for different periods, and some periods won't be workable.

Technically a really complicated circuit could probably be designed that would check the first couple of input gliders, make sure the delay was an even number, and then activate an appropriate circuit for that delay to fill in the halfway points with new gliders. But it would be huge, and it wouldn't be fast, and let's not go there.

By analogy to period doublers, triplers, quadruplers, and so on, a period halver is something that sends out two signals for every one sent in. Our various H-to-G0s in the Elementary Conduits Collection would count as period halvers for the particular period that's twice the delay between the two gliders.

Several other examples can be found in the gun collection, particularly the high double-digit periods below 79. Here's a random example of a gun containing a "period halver", the period 77 gun.

[AforAmpere]

Can anyone explain to me why the growing ship in the second rule here's front end speed limits at travelling at C/7? It seems really strange to me that the speed would approach C/7. I am probably missing some obvious reason. Also, is there some way to make this method have a growing ship with a front end that approaches an irrational number?

[dani]

I found this reaction posted by user 'Hunting':

Code: Select all

x = 4, y = 12, rule = B3/S23
b2o$o2bo$o2bo$b2o2$2bo$b3o$2obo$3o$3o$3o$b2o!

Although it's probably been seen many times. My question is, how would I go about searching for a reaction that turns this into a clean HWSS reflector? It seems possible, although I don't know much about conduit searching.

[KittyTac]

What's the systematic name for this?

Code: Select all

x = 15, y = 7, rule = B3/S23
2o3bo3bo3b2o$o3bobobobo3bo$b4obobob4o$6bobo$b4obobob4o$o3bobobobo3bo$
2o3bo3bo3b2o!

Also this:

Code: Select all

x = 19, y = 14, rule = B3/S23
3$5bo5b2o$4bobo2bo2bo$3bo2b6o$2bob2o$3bo2b6o$4bobo2bo2bo$5bo5b2o!

I think bookend-siamese-table-siamese-loaf siamese bookend-siamese-table-siamese-loaf siamese tub. Siameseception. I'll name it that.

[AforAmpere]

How many unique patterns are in an n x n square (meaning, not counting reflections and rotations as different patterns)? Or alternatively, how many isotropic non-totalistic conditions are there for higher ranged LTL rules?

[77topaz]

How many unique patterns are in an n x n square (meaning, not counting reflections and rotations as different patterns)? Or alternatively, how many isotropic non-totalistic conditions are there for higher ranged LTL rules?

I feel like this should be in the OEIS, but I can't seem to find it. f(1) = 2, f(2) = 5, f(3) = 102, right?

[wildmyron]

How many unique patterns are in an n x n square (meaning, not counting reflections and rotations as different patterns)? Or alternatively, how many isotropic non-totalistic conditions are there for higher ranged LTL rules?

I feel like this should be in the OEIS, but I can't seem to find it. f(1) = 2, f(2) = 5, f(3) = 102, right?

f(2) = 6, which leads to https://oeis.org/A054247

[AforAmpere]

f(2) = 6, which leads to https://oeis.org/A054247

Thanks. Sadly that means my goal of making an isotropic non-totalistic range 2 emulator (as in a script to generate rules) in Golly is fairly infeasible, as there are 2105872 different conditions for both Birth and Survival.

[muzik]

Do glider eaters composed solely of blocks exist?

[KittyTac]

Do glider eaters composed solely of blocks exist?

You could make a seed for an UCC made of blocks, that when triggered by a glider, constructs the UCC, then the UCC constructs the seed again, then self-destructs. Would be horribly slow and inefficient, but you asked for it.

[dani]

Do infinitely many GoEs exist in W110 or other 1DCA? A three cell row is one, I think

[Macbi]

Do infinitely many GoEs exist in W110 or other 1DCA? A three cell row is one, I think

That evolves from a two cell row.

But if there are any GoEs there are infinitely many. This is because every GoE contains an orphan, and then you can generate infinitely many GoEs by putting the orphan in arbitrary surroundings.

This raises a similar question though. Does rule 110 have infinitely many minimal orphans? Does Life?

[Hdjensofjfnen]

What's the systematic name for this?

Code: Select all

x = 15, y = 7, rule = B3/S23
2o3bo3bo3b2o$o3bobobobo3bo$b4obobob4o$6bobo$b4obobob4o$o3bobobobo3bo$
2o3bo3bo3b2o!

Also this:

Code: Select all

x = 19, y = 14, rule = B3/S23
3$5bo5b2o$4bobo2bo2bo$3bo2b6o$2bob2o$3bo2b6o$4bobo2bo2bo$5bo5b2o!

I think bookend-siamese-table-siamese-loaf siamese bookend-siamese-table-siamese-loaf siamese tub. Siameseception. I'll name it that.

#1: Mirrored long anvil with two long hooks.
#2: Mirrored bookend-siamese-table weld loaf weld tub weld loaf.

[KittyTac]

A weld is when the two SLs are joined together with modifications. A siamese is when the two SLs are joined together without modifications.

[wwei23]

1. ((Long bookend on long bookend) weld long long long beehive) on ((Long bookend on long bookend) weld long long long beehive)
2. (((Bookend on bookend) siamese (table on table)) siamese (loaf siamese loaf)) siamese tub
I used to do this kind of decomposition all the time when dealing with 1x256X2+1 objects.