Glider Destruction Of Still Lives, Oscillators, Etc.

[ThePlayzr]

1 glider to destroy the copperhead:

Code: Select all

.O
..O....OO..OO
OOO......OO
.........OO
......O.O..O.O
......O......O
.
......O......O
.......OO..OO
........OOOO
.
.........OO
.........OO

takes 201 generations, if you can find a faster 1-glider destruction, please post it

[confocaloid]

Assuming the same directions of the two colliding spaceships,

here are all potentially-relevant collisions I found right now in Golly after seeing your post and copying the pattern into Golly and manually enumerating all possible collisions of the same kind.

Note that this is intended more as an illustration of just how easy it is to "rediscover" results of this kind from scratch, compared to the headaches resulting from trying to collect them. These collisions are likely to be already known, first because it's easy to check them manually and likely an obvious "thing to do" back when the copperhead was discovered, and also because there are people in the local community who are interested in orthogonal c/10 technology specifically.

Code: Select all

x = 617, y = 38, rule = B3/S23
611bo2bo$581bo2bo26bo2bo$2bo29bo29bo29bo29bo29bo29bo29bo29bo29bo29bo
29bo29bo29bo29bo29bo29bo29bo9b2o18bo8b4o17bo8bo2bo17bo7bo4bo$obo27bobo
27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bo
bo27bobo27bobo27bobo27bobo7b2o2b2o14bobo8bo2bo15bobo7bo4bo14bobo7bo4bo
$b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o
28b2o28b2o28b2o9b2o17b2o9b2o17b2o7b6o15b2o7bo4bo15b2o7bo4bo$462b2o27bo
2bo24bo6bo53bo4bo24bo4bo$400b2o2b2o26b2o26b2o2b2o25bo2bo25bo4bo54bo4bo
23b3o2b3o$372b2o28b2o27bo2bo27b2o26bo4bo26b2o25bo2b2o2bo22b3o2b3o22bob
4obo$342b2o26b2o2b2o26b2o27bo2bo24bo6bo23bo4bo23b3o2b3o22bob4obo22bob
4obo23bo4bo$312b2o27b4o27b2o25bobo2bobo23bo4bo24bo4bo25b4o24b2o4b2o22b
obo2bobo23bo4bo$312b2o55bo6bo22bo6bo23bo4bo26b2o26b2o2b2o$311bo2bo25b
6o24bo4bo55b4o24b3o2b3o23bo4bo116b2o$281b4o26b4o26b4o27b2o25bo6bo23b2o
2b2o23b2o4b2o23bo4bo26b2o28b2o28b2o28b2o$310bob2obo53b3o2b3o23b2o2b2o
24bo4bo85bo2bo27b2o28b2o$252b2o27bo2bo26bo2bo25b2o2b2o23b2o4b2o24b4o
25bo4bo$222b2o26b2o2b2o24bob2obo52b2obo2bob2o114b2o27b4o$221bo2bo27b2o
26bo4bo24b2o2b2o25bo2bo57b2o57bo2bo27b2o$192b2o26b2o2b2o23bo6bo52bo6bo
55b2o28b2o27b4o$132b2o56b2o2b2o24b2o2b2o24bo4bo24bo4bo85bo2bo57b2o$
102b2o27b4o25b2o2b2o26b2o26bob2obo26b2o26b2o2b2o24bo4bo26b2o$72b2o28b
2o56b2o2b2o23bo6bo25b2o25b3o2b3o23b6o25bo2bo27b2o$42b2o27b4o26bo2bo25b
6o23b3o2b3o23bo4bo24bo4bo23b2o4b2o24bo2bo27b2o$41bo2bo56b4o26b4o24b3o
2b3o25b2o25b2o4b2o55b2o$41bo2bo25b6o24bob2obo83b3o2b3o85b2o$40bo4bo25b
4o26bo2bo25b2o2b2o23bo6bo22b2o4b2o55b2o$11bo2bo25bo4bo82b2obo2bob2o21b
o2b2o2bo55b2o27bo2bo$11bo2bo26b4o25b2o2b2o24b2o2b2o25bo2bo25b6o55bo2bo
$10bo4bo24b2o2b2o22b2obo2bob2o21bo6bo85b2o27bo2bo$10bo4bo24bo4bo25bo2b
o116bo2bo$10bo4bo24bo4bo54bo4bo26b2o28b2o$10bo4bo85bo2bo27b2o28b2o$9b
3o2b3o55b2o28b2o$9bob4obo24b4o27b2o$10bo4bo26b2o3$12b2o$12b2o!

1 glider to destroy the copperhead:

Code: Select all

.O
..O....OO..OO
OOO......OO
.........OO
......O.O..O.O
......O......O
.
......O......O
.......OO..OO
........OOOO
.
.........OO
.........OO

takes 201 generations, if you can find a faster 1-glider destruction, please post it

[ThePlayzr]

new one glider destruction of the copperhead which takes 53 generations:

Code: Select all

...O
....O
..OOO
.
.
.
.
.
.
.
.OO..OO
...OO
...OO
O.O..O.O
O......O
.
O......O
.OO..OO
..OOOO
.
...OO
...OO

[confocaloid]

Please read again previous posts by other people (including myself).

Your collision is the same as the generation 42 of the first collision in my preceding post. It isn't new. Even if it wasn't present in my post, it wouldn't be new anyway.

new one glider destruction of the copperhead which takes 53 generations:

Code: Select all

...O
....O
..OOO
.
.
.
.
.
.
.
.OO..OO
...OO
...OO
O.O..O.O
O......O
.
O......O
.OO..OO
..OOOO
.
...OO
...OO

[ThePlayzr]

Assuming the same directions of the two colliding spaceships,

here are all potentially-relevant collisions I found right now in Golly after seeing your post and copying the pattern into Golly and manually enumerating all possible collisions of the same kind.

Note that this is intended more as an illustration of just how easy it is to "rediscover" results of this kind from scratch, compared to the headaches resulting from trying to collect them. These collisions are likely to be already known, first because it's easy to check them manually and likely an obvious "thing to do" back when the copperhead was discovered, and also because there are people in the local community who are interested in orthogonal c/10 technology specifically.

Code: Select all

x = 617, y = 38, rule = B3/S23
611bo2bo$581bo2bo26bo2bo$2bo29bo29bo29bo29bo29bo29bo29bo29bo29bo29bo
29bo29bo29bo29bo29bo29bo29bo9b2o18bo8b4o17bo8bo2bo17bo7bo4bo$obo27bobo
27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bo
bo27bobo27bobo27bobo27bobo7b2o2b2o14bobo8bo2bo15bobo7bo4bo14bobo7bo4bo
$b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o
28b2o28b2o28b2o9b2o17b2o9b2o17b2o7b6o15b2o7bo4bo15b2o7bo4bo$462b2o27bo
2bo24bo6bo53bo4bo24bo4bo$400b2o2b2o26b2o26b2o2b2o25bo2bo25bo4bo54bo4bo
23b3o2b3o$372b2o28b2o27bo2bo27b2o26bo4bo26b2o25bo2b2o2bo22b3o2b3o22bob
4obo$342b2o26b2o2b2o26b2o27bo2bo24bo6bo23bo4bo23b3o2b3o22bob4obo22bob
4obo23bo4bo$312b2o27b4o27b2o25bobo2bobo23bo4bo24bo4bo25b4o24b2o4b2o22b
obo2bobo23bo4bo$312b2o55bo6bo22bo6bo23bo4bo26b2o26b2o2b2o$311bo2bo25b
6o24bo4bo55b4o24b3o2b3o23bo4bo116b2o$281b4o26b4o26b4o27b2o25bo6bo23b2o
2b2o23b2o4b2o23bo4bo26b2o28b2o28b2o28b2o$310bob2obo53b3o2b3o23b2o2b2o
24bo4bo85bo2bo27b2o28b2o$252b2o27bo2bo26bo2bo25b2o2b2o23b2o4b2o24b4o
25bo4bo$222b2o26b2o2b2o24bob2obo52b2obo2bob2o114b2o27b4o$221bo2bo27b2o
26bo4bo24b2o2b2o25bo2bo57b2o57bo2bo27b2o$192b2o26b2o2b2o23bo6bo52bo6bo
55b2o28b2o27b4o$132b2o56b2o2b2o24b2o2b2o24bo4bo24bo4bo85bo2bo57b2o$
102b2o27b4o25b2o2b2o26b2o26bob2obo26b2o26b2o2b2o24bo4bo26b2o$72b2o28b
2o56b2o2b2o23bo6bo25b2o25b3o2b3o23b6o25bo2bo27b2o$42b2o27b4o26bo2bo25b
6o23b3o2b3o23bo4bo24bo4bo23b2o4b2o24bo2bo27b2o$41bo2bo56b4o26b4o24b3o
2b3o25b2o25b2o4b2o55b2o$41bo2bo25b6o24bob2obo83b3o2b3o85b2o$40bo4bo25b
4o26bo2bo25b2o2b2o23bo6bo22b2o4b2o55b2o$11bo2bo25bo4bo82b2obo2bob2o21b
o2b2o2bo55b2o27bo2bo$11bo2bo26b4o25b2o2b2o24b2o2b2o25bo2bo25b6o55bo2bo
$10bo4bo24b2o2b2o22b2obo2bob2o21bo6bo85b2o27bo2bo$10bo4bo24bo4bo25bo2b
o116bo2bo$10bo4bo24bo4bo54bo4bo26b2o28b2o$10bo4bo85bo2bo27b2o28b2o$9b
3o2b3o55b2o28b2o$9bob4obo24b4o27b2o$10bo4bo26b2o3$12b2o$12b2o!

1 glider to destroy the copperhead:

Code: Select all

.O
..O....OO..OO
OOO......OO
.........OO
......O.O..O.O
......O......O
.
......O......O
.......OO..OO
........OOOO
.
.........OO
.........OO

takes 201 generations, if you can find a faster 1-glider destruction, please post it

ok then can you find me some glider destructions for sir robin in golly? because I don't have discord.

[confocaloid]

Please trim the long quote (forum rule 3d). viewtopic.php?f=3&t=2092

You don't need discord to find glider destructions. I suggest to download Golly and learn how to use it (and avoid posting results that are easy to rediscover).

Without a good reason to search for glider destructions of Sir Robin (which doesn't currently have any known glider construction), I'm unlikely to spend too much time on this puzzle.

ok then can you find me some glider destructions for sir robin in golly? because I don't have discord.

[ThePlayzr]

this may be true, but your 4th, 5th, 8th, and 2nd last glider destructions are not full destructions.

Assuming the same directions of the two colliding spaceships,

here are all potentially-relevant collisions I found right now in Golly after seeing your post and copying the pattern into Golly and manually enumerating all possible collisions of the same kind.

Note that this is intended more as an illustration of just how easy it is to "rediscover" results of this kind from scratch, compared to the headaches resulting from trying to collect them. These collisions are likely to be already known, first because it's easy to check them manually and likely an obvious "thing to do" back when the copperhead was discovered, and also because there are people in the local community who are interested in orthogonal c/10 technology specifically.

Code: Select all

x = 617, y = 38, rule = B3/S23
611bo2bo$581bo2bo26bo2bo$2bo29bo29bo29bo29bo29bo29bo29bo29bo29bo29bo
29bo29bo29bo29bo29bo29bo29bo9b2o18bo8b4o17bo8bo2bo17bo7bo4bo$obo27bobo
27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bo
bo27bobo27bobo27bobo27bobo7b2o2b2o14bobo8bo2bo15bobo7bo4bo14bobo7bo4bo
$b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o
28b2o28b2o28b2o9b2o17b2o9b2o17b2o7b6o15b2o7bo4bo15b2o7bo4bo$462b2o27bo
2bo24bo6bo53bo4bo24bo4bo$400b2o2b2o26b2o26b2o2b2o25bo2bo25bo4bo54bo4bo
23b3o2b3o$372b2o28b2o27bo2bo27b2o26bo4bo26b2o25bo2b2o2bo22b3o2b3o22bob
4obo$342b2o26b2o2b2o26b2o27bo2bo24bo6bo23bo4bo23b3o2b3o22bob4obo22bob
4obo23bo4bo$312b2o27b4o27b2o25bobo2bobo23bo4bo24bo4bo25b4o24b2o4b2o22b
obo2bobo23bo4bo$312b2o55bo6bo22bo6bo23bo4bo26b2o26b2o2b2o$311bo2bo25b
6o24bo4bo55b4o24b3o2b3o23bo4bo116b2o$281b4o26b4o26b4o27b2o25bo6bo23b2o
2b2o23b2o4b2o23bo4bo26b2o28b2o28b2o28b2o$310bob2obo53b3o2b3o23b2o2b2o
24bo4bo85bo2bo27b2o28b2o$252b2o27bo2bo26bo2bo25b2o2b2o23b2o4b2o24b4o
25bo4bo$222b2o26b2o2b2o24bob2obo52b2obo2bob2o114b2o27b4o$221bo2bo27b2o
26bo4bo24b2o2b2o25bo2bo57b2o57bo2bo27b2o$192b2o26b2o2b2o23bo6bo52bo6bo
55b2o28b2o27b4o$132b2o56b2o2b2o24b2o2b2o24bo4bo24bo4bo85bo2bo57b2o$
102b2o27b4o25b2o2b2o26b2o26bob2obo26b2o26b2o2b2o24bo4bo26b2o$72b2o28b
2o56b2o2b2o23bo6bo25b2o25b3o2b3o23b6o25bo2bo27b2o$42b2o27b4o26bo2bo25b
6o23b3o2b3o23bo4bo24bo4bo23b2o4b2o24bo2bo27b2o$41bo2bo56b4o26b4o24b3o
2b3o25b2o25b2o4b2o55b2o$41bo2bo25b6o24bob2obo83b3o2b3o85b2o$40bo4bo25b
4o26bo2bo25b2o2b2o23bo6bo22b2o4b2o55b2o$11bo2bo25bo4bo82b2obo2bob2o21b
o2b2o2bo55b2o27bo2bo$11bo2bo26b4o25b2o2b2o24b2o2b2o25bo2bo25b6o55bo2bo
$10bo4bo24b2o2b2o22b2obo2bob2o21bo6bo85b2o27bo2bo$10bo4bo24bo4bo25bo2b
o116bo2bo$10bo4bo24bo4bo54bo4bo26b2o28b2o$10bo4bo85bo2bo27b2o28b2o$9b
3o2b3o55b2o28b2o$9bob4obo24b4o27b2o$10bo4bo26b2o3$12b2o$12b2o!

1 glider to destroy the copperhead:

Code: Select all

.O
..O....OO..OO
OOO......OO
.........OO
......O.O..O.O
......O......O
.
......O......O
.......OO..OO
........OOOO
.
.........OO
.........OO

takes 201 generations, if you can find a faster 1-glider destruction, please post it

[confocaloid]

this may be true, but your 4th, 5th, 8th, and 2nd last glider destructions are not full destructions.
[very long and unnecessary quote omitted]

Obviously, and that's simply because they weren't all intended to be glider destructions. Most of them are, and I decided to add other interesting collisions I found.

Again, please edit your posts and trim the long quotes (forum rule 3d: "... only quote text that is actually relevant to your post ...").

Please trim the long quote (forum rule 3d). viewtopic.php?f=3&t=2092 [...]

[PK22]

(Moving discussion of the 2G destruction research here, since it's more relevant)

(...)
EDIT: N <= 23 now, after an overnight search using an HTTP server. 24 hours seems like a more accurate estimate for getting N <= 24.

It took several overnight runs of a custom search program, but now all still lifes up to 24 bits have a 1G or 2G destruction, which can be found in this repo.

I have no clue what size the smallest SL that cannot be destroyed by 2G will be, because while there are more still lifes as they get larger, they also seem to become more fragile - lots of the xs24s had clean 1G destructions, because there are more lanes for glider collisions, and many SL components are fragile, like diagonal lines or aircraft carriers. If it's an xs25, I might be able to track it down by the end of the year; if not, it's going to require a rewrite of the search program in a faster language than Python.

[higumachan]

I may have found a finite stable constellation that requires exactly three gliders for clean destruction. I haven't been able to find a previous construction of this kind, but I may have missed one.

The target consists of three widely separated blocks, with origins at

Code: Select all

(0, 0)
(100000, 300000)
(300000, 800000)

so the target has population 12.

Code: Select all

x = 300002, y = 800002, rule = B3/S23
2o$2o299999$100000b2o$100000b2o499999$
300000b2o$300000b2o!

I have a computer-assisted proof that no pair of arbitrarily rewindable input gliders can cleanly destroy this constellation.

The proof is not based on searching a finite range of launch positions or time offsets. Instead, it reduces all possible interactions to finitely many local cases and then uses geometric separation to lift the result to unrestricted positions and time differences.

A few details:

• All one-glider interactions with a block are exhaustively classified.
• Cases where the two input gliders collide with each other before reaching a block are also included, including collisions that produce additional escaping gliders.
• Cases where both gliders interact with the same block reaction, including arbitrarily late interactions with periodic ash, are included.
• 103,661 local cases were checked in total.
• 4,384 terminate in the empty pattern.
• 99,277 are certified as unions of mutually noninteracting periodic/translating components.
• 0 cases remain unresolved.
• The maximum verification time was 65,536 generations and the maximum certified period was 30.

The resulting certified locality bound is R = 65,778. The three block positions were chosen so that their separations in x, y, x-y, and x+y are all large enough relative to this bound. This guarantees that any reaction involving both input gliders can affect at most two of the original blocks. Therefore at least one original block survives unchanged forever.

There is also an explicit three-glider destruction: one glider is sent to each block, and the entire pattern is empty after 32 generations. Thus the glider destruction cost of this constellation is exactly 3.

I am deliberately calling this a stable constellation rather than claiming that it resolves the LifeWiki question about the smallest still life without a two-glider destruction, since that question may be intended to mean a single still-life object (or a strict still life).

Does anyone know whether an equivalent construction, or a more general argument of this kind, has been posted before?

I have the verification code, generated certificates, and reproduction procedure available, and I would be happy to share them if there is interest in checking the result.