Talk:Conway's Game of Life

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Needs references. Geometry guy 22:52, 16 June 2007 (UTC)

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Help with this template Comments: edit – history – watch – refresh Needs references. Geometry guy 22:52, 16 June 2007 (UTC)

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[edit] Animated GIF of a LWSS

In the same manner I added an animation of a glider (below), I did it now for a LWSS. Feel free to improve it. RodrigoCamargo (talk) 16:35, 16 March 2008 (UTC)

Very nice animations! I'm interested to know whether you created them manually (eg. in Photoshop), or used some software to generate them automatically? I know Golly allows the creation of very basic animated GIFs, but nothing as nice as your animations. —Slowspace (talk) 19:07, 29 March 2008 (UTC)

[edit] Animated GIF of a glider

I find the graphic "standard" used in the pictures inside the article really interesting: grey grid on a white background, with black live cells. However, one of the most interesting pictures of the article - the animated glider - does not fit this standard. So I replaced the old image with this new one that I did. I noticed also that the old image was also used in some other articles. Maybe someone finds it better to replace the old image, uploading it again with the same name of it. Feel free to do it (giving proper credit) or to modify it, as I release it into the public domain. RodrigoCamargo (talk) 01:12, 11 March 2008 (UTC)

[edit] Life32

Re the ref: I linked to a webpage about Life32... Perhaps the source should in fact be Life32 itself. I'm sure it's OK but needs to be made clear. Bookgirl 12:56, 30 Apr 2004 (UTC)

The page you linked does not seem to mention Life32 at all. (Perhaps you put the wrong link in by mistake?) Anyway, I've changed it to point to the main download page for Life32. --Zundark 13:06, 30 Apr 2004 (UTC)

Ah, yes. I went to the same Life32 download page and got the link from this part: "Life32 is a player for Conway's game of life and related cellular automa. If that does not ring a bell, look here". What I linked to was the 'here'. There was a logic there (sort of). Your solution better, tho. :-) Bookgirl 13:20, 30 Apr 2004 (UTC)

[edit] Oscillating objects

Thre are some other oscilating objects in 23/3 (2G3):


0-Laser: XX         XX     4-Laser   XX
         X     <=>  XX               X X
            X         XX
           XX         XX               X X

                                         X X
                                          XX


Pulsator:    X    X     Unruhe(2):  X         XX
           XX XXXX XX               XX  <=>  X
             X    X                 XX          X
                                     X        XX

4-Takter:       XX
                XX

              XXXX
          XX X  X X
          XX XX   X
             X X  X XX
             X    X XX
              XXXX

              XX
              XX

Here a special List:

Name:       Maximum:  Minimum:    Art:             4G3   45G3   2G3
                                                  34/3  345/3  23/3
-------------------------------------------------------------------
Kegel            G3       0  45678G3  oszilierend   X      X
Pedal            G3       01 45678G3  oszilierend   X      X
Strudel          G3          45678G3  oszilierend   X      X
Unruhe           G3       0 245678G3  oszilierend   X      X
0G3_OBJ         0G3       01 45678G3  oszilierend  
1G3_OBJ(1)      1G3       01 45678G3  oszilierend
1G3_OBJ(2)      1G3       01 45678G3  oszilierend
1G3_OBJ(3)      1G3       01 45678G3  oszilierend
1G3_OBJ(4)      1G3       01 45678G3  oszilierend
Pseudo_Gleiter  1G3       01   678G3  oszilierend
2G3_OBJ(1)      2G3       0 245678G3  oszilierend                X
Gleiter         2G3       0 2 5678G3  bewegend                   X
n-Laser (n=0)   2G3       012 5678G3  oszilierend                X
n-Laser (n=2)   2G3       0 245678G3  oszilierend                X
n-Laser (n>2)   2G3         245678G3  oszilierend                X
Pulsator        2G3       0 2     G3  oszilierend                X
Segler(1)       2G3         2   78G3  bewegend                   X
Segler(2)       2G3         2    8G3  bewegend                   X
Segler(3)       2G3         2     G3  bewegend                   X
Fontaine        2G3       0 2  678G3  oszilierend                X
Unruhe(2)       2G3       0 2 5678G3  oszilierend                X
Viertakter      2G3       0 2 5678G3  oszilierend                X
4G3_OBJ(3)      4G3       0  4  78G3  oszilierend   X
Frosch          4G3       01 45678G3  oszilierend   X      X
Strange         4G3       0  4  78G3  oszilierend   X
Schwimmer(1)    5G3       0  456 8G3  bewegend      X      X
Schwimmer(2)    5G3       0   56 8G3  bewegend             X
5G3-Segler      5G3       ??????????  bewegend
5G3-Beweger     5G3       ??????????  bewegend

(not complete)

--217.233.250.157 10:26, 11 Mar 2004 (UTC) in www.wikipedia.de Benutzer:Arbol01

Pseudo_glider:   X       X        X       X
                X   => X   X => X  X => X X
               XXXX     XXX     X  X     XX
                        XX       X X      X

Four 13/3-objects:  X X      X X       X       X    X      X    X      X
                    X X <=> X   X      X      X     X  <=>  X   X  <=>  X
                    X X      X X        X <=>  X     X      X    X     X
                                       X      X                 X      X
                                       X       X

--217.233.250.157 10:40, 11 Mar 2004 (UTC)

[edit] R-pentomino?

In this article there is written about a "R-pentomino", yet in the article on pentomino's there is not mentioned a such pentomino.

True. It should have said "R-shaped F-pentomino". I've fixed it. - UtherSRG 18:19, Feb 5, 2005 (UTC)

In Life it's always called the R-pentomino, because that's what Conway called it. I've reworded it. (Also, the anonymous poster above is incorrect in saying that there is no mention of "R-penomino" in the pentomino article. There is such a mention, added by Maury Markowitz more than a year ago.) --Zundark, 6 Feb 2005 (UTC)

[edit] positional variations and local connectivity variations

all the variations in the life family considers the _number_ of neighboring cells. Where can one read about 2d CA that considers the position of neighbors, besides number? Also, there is zero info on life with different grids. (i.e. triangular, hexagonal, or any tilings/network) Thanks. Xah Lee 00:44, 2005 Apr 5 (UTC)

Such CA wouldn't be life-like, and don't really deserve a place in this article. Perhaps you would be better off requesting some references for such games in the Cellular automaton article, or better yet creating a List of cellular automata. 192.152.5.250 16:35, 3 Jun 2005 (UTC)

Back in the 1980s, I implemented a simple version of Life on the Commodore PET using the standard rules. I also tried a variation based on the 8 "neighbouring" cells being one knight's move away, rather than the usual 8 cells in the surrounding square, albeit still using the standard rules. Thus it acquired some sense of action at a distance. Seeding it with the R-pentomino gave results that seemed even more chaotic and unpredictable than for the original game. This concept was never published, as I did not even think of it as "original research". Back then I considered naming it as KnightLife, though such a name nowadays gives a large number of unrelated hits in Google. I would be quite happy for others to take this further. DFH 14:07, 17 September 2005 (UTC)

[edit] Simple Replicator

If you glue the east and west sides together then a horizantial line going all the way around the universe is a replicator.--SurrealWarrior 19:31, 18 July 2005 (UTC)

Should there not always be a finite amount of live cells in a starting position? Your line would be infinitely long. Qevlarr 21:24, 3 January 2007 (UTC)

[edit] Can it be done?

Can a Thue generating glider gun or still life puffer be made?--SurrealWarrior 20:09, 18 July 2005 (UTC)

[edit] Overcategorisation

The new "links" section overcategorizes and is far less than useful.

Some sites have both patterns and also software available for download. There's no consistent way to categorize links to such sites.

If the links don't direct users searching for software to Al Hensel's site they aren't very useful. Al has created the best damn Java Life Applet anywhere, he's giving it away for free, but unless a Wikipedia user checks the "External Article Links" section and clicks on the link they won't find it.

Hensel's free applet is nowhere to be found in the "Life Program Links" section.

Links which are most relevent should be placed first while links which are least relevent should go last. I fail to see how "Terminal-based Game of Life for Unix/Linux" is relevent enough to Wikipedia users to place it second in a list of fourteen. Mirek's free program is ninth. Who knows or cares about the "J Programming Language" in the third link?

An anon user added this link to the bottom: *Thermodynamic Life Game - New Thermodynamic Life Game, based on "Conservation of Energy Law". This is to a chinese language (largely) article. I've removed this (as it is not an English page) but thought I would leave that link here on the off chance, and all that. Dxco 05:17, 1 November 2005 (UTC)

Ok. The links section now has way way way more links than needed. Could we perhaps not add anymore? I fear that this article will soon have more lines of links than article text :P Dxco 19:06, 27 December 2005 (UTC)

[edit] Stephen Wolfram's NKOSc mention?

Shouldn't there be some sort of mention of Stephen Wolfram and his New Kind of Science?--sciyoshi 10:10, 11 November 2005 (UTC)

[edit] B1/S23 Universe Properties

I was fooling around in The Game of Life and found that in the B1/S23 universe that Sierpinski's triangle appeared in very simple formations. I don't know why this is (I'm just a high school student) but it seems interesting enough to merit a mention in the article. I would invite someone else to write this because I can't explain it.

Sierpinski's triangle would appear in simple formations, such as a 5x5 cross.

If anyone can explain this in laymans terms I would like to hear it.

--Directrixx 20:28, 2 February 2006 (UTC)

[edit] Clarify: blinker and boundary conditions (?)

Is it me? I don't understand why the blinker should be an oscillator. I suspect this might have to do with periodic boundary conditions, but the text seems obscure. Please clarify 213.140.21.231 11:31, 12 February 2006 (UTC)

See oscillator. Why shouldn't it be? Dysprosia 13:14, 12 February 2006 (UTC)

[edit] Computer time

At one time it was claimed that, since 1970, more computer time worldwide had been devoted to the Game of Life than any other single activity[citation needed].

This is pretty useless when it doesn't mention when this "one time" was. At least today it seems pretty far off, compared to e.g. weather simulations or render farms. --Big gun 22:55, 21 July 2006 (UTC)

Agreed. I have removed the statement. If a solid citation can be provided for this you're more than welcome to reinstate it, but I am extremely skeptical. --INTRIGUEBLUE (talk|contribs) 07:16, 6 November 2006 (UTC)

[edit] Infinite-3

is not true, try it yourself. 89.1.175.210 18:28, 24 July 2006 (UTC)

I tried it and it worked (two block-laying switch engines), so I think you must have entered it incorrectly. Try copying and pasting the following into your favorite Life app: ********.*****...***......*******.***** --Zundark 21:16, 24 July 2006 (UTC)

The pattern is totally correct. Who discovered it? And when? She/He deserves credit. Thanks in advance! -- Pichote (talk) 01:16, 8 June 2008 (UTC)

I found the answer here and the pattern here:) In October 1998. Paul Callahan did an exhaustive search, finding the smallest example with is 39x1 and produces two block-laying switch engines. Well, it has been almost ten years since then -- Pichote (talk) 01:29, 8 June 2008 (UTC)

Paul Callahan found it and reported it to a private mailing list of Life enthusiasts in October 1998. The method was exhaustive enumeration of sequences that don't contain any isolated live cells or pairs of live cells. —David Eppstein (talk) 01:29, 8 June 2008 (UTC)

Nor composed only by 3-cell and 4-cells groups. :) -- Pichote (talk) 01:36, 8 June 2008 (UTC)

You could make that restriction as well, but Callahan's email only mentions the 1-cell and 2-cell groups. —David Eppstein (talk) 01:41, 8 June 2008 (UTC)

Thank you! -- Pichote (talk) 01:46, 8 June 2008 (UTC)

[edit] Question

Maybe a wrong place to put this here, but I've done some of my own still lifes (which is pretty easy), but I'm wanting to make my own oscillator.

Is there any tips to make oscillators? I mean, here's one I'm trying to do:

#D0116C174
#r S23/B3
#P -6 -9
..**...
..**...
.......
..****.
.*....*
.**...*
*...**.
*....*.
.****..
.......
...**..
...**..

(just copy and paste that into Life32)

I'm trying to make my own "hustler" or "babbling brook", but dunno what term is correct for that =P

I was wondering if anyone can redirect me something like a forum regarding Life32, so I can get more help there.

So, apologies if this is in the wrong place =) --Burai 10:36, 5 August 2006 (UTC)

It would be hard to find any really new non-compound oscillators by hand these days, as so much is now known. Usually these things are now found using search programs such as WinLifeSearch. You can get some of these programs from Jason Summers' web site. --Zundark 19:19, 5 August 2006 (UTC)

[edit] Sierpinski Gasket???

I found this when messing with Life32.Doomed Rasher 18:05, 23 August 2006 (UTC)

Sierpinski Gasket???

Okay, okay, fine, I'll be more descriptive next time. The first image is generated by placing a sufficiently long horizontal/vertical line segment in Life 32 with the regular Conway's rules. When the two gaskets collide the stram of gliders that it shot out will form a rhombus with angles 120 and 60. The second image which I am kind enough to provide is the generation of a perfect Sierpinski gasket with a diagonal line segment sufficiently long in the /2 universe. The entire gaket is made up of the /2 blinker, two diagonally adjacent cells. When the two gaskets collide either the life form remains stable or the gasket will be consumed by chaos by the /2 exploder, depending on the length of the diagonal segment (even=chaos, odd=stable life).

I found the same results at a Conway's game of Life Applet by Alan Hensel. I call it The Principal of Collapsing Rods.

Perfect sierpinski gasket in the /2 universe.

P.S. Every lightspeed spaceship in /2 that has wings longer than two units is a puffer.

P.P.S. Here's the code for the initiation of the second gasket if you want it.

#D010493E8
x = 711, y = 711, rule = S/B2
710bo$709bo$708bo$707bo$706bo$705bo$704bo$703bo$702bo$701bo$700bo$699b
o$698bo$697bo$696bo$695bo$694bo$693bo$692bo$691bo$690bo$689bo$688bo$
687bo$686bo$685bo$684bo$683bo$682bo$681bo$680bo$679bo$678bo$677bo$676b
o$675bo$674bo$673bo$672bo$671bo$670bo$669bo$668bo$667bo$666bo$665bo$
664bo$663bo$662bo$661bo$660bo$659bo$658bo$657bo$656bo$655bo$654bo$653b
o$652bo$651bo$650bo$649bo$648bo$647bo$646bo$645bo$644bo$643bo$642bo$
641bo$640bo$639bo$638bo$637bo$636bo$635bo$634bo$633bo$632bo$631bo$630b
o$629bo$628bo$627bo$626bo$625bo$624bo$623bo$622bo$621bo$620bo$619bo$
618bo$617bo$616bo$615bo$614bo$613bo$612bo$611bo$610bo$609bo$608bo$607b
o$606bo$605bo$604bo$603bo$602bo$601bo$600bo$599bo$598bo$597bo$596bo$
595bo$594bo$593bo$592bo$591bo$590bo$589bo$588bo$587bo$586bo$585bo$584b
o$583bo$582bo$581bo$580bo$579bo$578bo$577bo$576bo$575bo$574bo$573bo$
572bo$571bo$570bo$569bo$568bo$567bo$566bo$565bo$564bo$563bo$562bo$561b
o$560bo$559bo$558bo$557bo$556bo$555bo$554bo$553bo$552bo$551bo$550bo$
549bo$548bo$547bo$546bo$545bo$544bo$543bo$542bo$541bo$540bo$539bo$538b
o$537bo$536bo$535bo$534bo$533bo$532bo$531bo$530bo$529bo$528bo$527bo$
526bo$525bo$524bo$523bo$522bo$521bo$520bo$519bo$518bo$517bo$516bo$515b
o$514bo$513bo$512bo$511bo$510bo$509bo$508bo$507bo$506bo$505bo$504bo$
503bo$502bo$501bo$500bo$499bo$498bo$497bo$496bo$495bo$494bo$493bo$492b
o$491bo$490bo$489bo$488bo$487bo$486bo$485bo$484bo$483bo$482bo$481bo$
480bo$479bo$478bo$477bo$476bo$475bo$474bo$473bo$472bo$471bo$470bo$469b
o$468bo$467bo$466bo$465bo$464bo$463bo$462bo$461bo$460bo$459bo$458bo$
457bo$456bo$455bo$454bo$453bo$452bo$451bo$450bo$449bo$448bo$447bo$446b
o$445bo$444bo$443bo$442bo$441bo$440bo$439bo$438bo$437bo$436bo$435bo$
434bo$433bo$432bo$431bo$430bo$429bo$428bo$427bo$426bo$425bo$424bo$423b
o$422bo$421bo$420bo$419bo$418bo$417bo$416bo$415bo$414bo$413bo$412bo$
411bo$410bo$409bo$408bo$407bo$406bo$405bo$404bo$403bo$402bo$401bo$400b
o$399bo$398bo$397bo$396bo$395bo$394bo$393bo$392bo$391bo$390bo$389bo$
388bo$387bo$386bo$385bo$384bo$383bo$382bo$381bo$380bo$379bo$378bo$377b
o$376bo$375bo$374bo$373bo$372bo$371bo$370bo$369bo$368bo$367bo$366bo$
365bo$364bo$363bo$362bo$361bo$360bo$359bo$358bo$357bo$356bo$355bo$354b
o$353bo$352bo$351bo$350bo$349bo$348bo$347bo$346bo$345bo$344bo$343bo$
342bo$341bo$340bo$339bo$338bo$337bo$336bo$335bo$334bo$333bo$332bo$331b
o$330bo$329bo$328bo$327bo$326bo$325bo$324bo$323bo$322bo$321bo$320bo$
319bo$318bo$317bo$316bo$315bo$314bo$313bo$312bo$311bo$310bo$309bo$308b
o$307bo$306bo$305bo$304bo$303bo$302bo$301bo$300bo$299bo$298bo$297bo$
296bo$295bo$294bo$293bo$292bo$291bo$290bo$289bo$288bo$287bo$286bo$285b
o$284bo$283bo$282bo$281bo$280bo$279bo$278bo$277bo$276bo$275bo$274bo$
273bo$272bo$271bo$270bo$269bo$268bo$267bo$266bo$265bo$264bo$263bo$262b
o$261bo$260bo$259bo$258bo$257bo$256bo$255bo$254bo$253bo$252bo$251bo$
250bo$249bo$248bo$247bo$246bo$245bo$244bo$243bo$242bo$241bo$240bo$239b
o$238bo$237bo$236bo$235bo$234bo$233bo$232bo$231bo$230bo$229bo$228bo$
227bo$226bo$225bo$224bo$223bo$222bo$221bo$220bo$219bo$218bo$217bo$216b
o$215bo$214bo$213bo$212bo$211bo$210bo$209bo$208bo$207bo$206bo$205bo$
204bo$203bo$202bo$201bo$200bo$199bo$198bo$197bo$196bo$195bo$194bo$193b
o$192bo$191bo$190bo$189bo$188bo$187bo$186bo$185bo$184bo$183bo$182bo$
181bo$180bo$179bo$178bo$177bo$176bo$175bo$174bo$173bo$172bo$171bo$170b
o$169bo$168bo$167bo$166bo$165bo$164bo$163bo$162bo$161bo$160bo$159bo$
158bo$157bo$156bo$155bo$154bo$153bo$152bo$151bo$150bo$149bo$148bo$147b
o$146bo$145bo$144bo$143bo$142bo$141bo$140bo$139bo$138bo$137bo$136bo$
135bo$134bo$133bo$132bo$131bo$130bo$129bo$128bo$127bo$126bo$125bo$124b
o$123bo$122bo$121bo$120bo$119bo$118bo$117bo$116bo$115bo$114bo$113bo$
112bo$111bo$110bo$109bo$108bo$107bo$106bo$105bo$104bo$103bo$102bo$101b
o$100bo$99bo$98bo$97bo$96bo$95bo$94bo$93bo$92bo$91bo$90bo$89bo$88bo$
87bo$86bo$85bo$84bo$83bo$82bo$81bo$80bo$79bo$78bo$77bo$76bo$75bo$74bo$
73bo$72bo$71bo$70bo$69bo$68bo$67bo$66bo$65bo$64bo$63bo$62bo$61bo$60bo$
59bo$58bo$57bo$56bo$55bo$54bo$53bo$52bo$51bo$50bo$49bo$48bo$47bo$46bo$
45bo$44bo$43bo$42bo$41bo$40bo$39bo$38bo$37bo$36bo$35bo$34bo$33bo$32bo$
31bo$30bo$29bo$28bo$27bo$26bo$25bo$24bo$23bo$22bo$21bo$20bo$19bo$18bo$
17bo$16bo$15bo$14bo$13bo$12bo$11bo$10bo$9bo$8bo$7bo$6bo$5bo$4bo$3bo$bb
o$bo$o!

It works in life 32.Doomed Rasher 21:23, 13 September 2006 (UTC)

By the way, the ending is stable, so you don't have to worry about your computer overloading. Two main gaskets and two miniature ones branching off showing the general SG structure and why not every diagonal line segment leads to two side-by-side gaskets.Doomed Rasher 21:36, 13 September 2006 (UTC)

This looks more relevant for Seeds (CA) since that's the rule you're using. However Sierpinski gaskets are known for other rules, e.g. see this replicator-base Sierpinski in HighLife. —David Eppstein 21:38, 13 September 2006 (UTC)

[edit] WinLifeSearch question..

If anyone has the WinLifeSearch program, I've got a problem... You know this "Translation" thing, right? Well, it says that you can use that for spaceship and fuse searches. The thing is, I don't understand it, even if I read the help files...

So can someone give me some advice on how to use the Translation section correctly?

PS: If this is in the wrong place, I apologise.

--Burai 17:18, 26 September 2006 (UTC)

[edit] Too many Life program links

The "life program links" section is getting unmanageably and uselessly large. There must have been millions of Life programs out there (he says, having probably written a dozen or two himself) and it's not helpful to anybody to list them all. Can we agree on some standards for how notable a program must be to be listed here? I'd like a criterion that leads to a very small number (at most half a dozen) of widely used and generally usable systems, such that for each one we can state clear reasons for why that system is notable enough to deserve its place on the list, e.g.

Mirek's Cellebration: widely used Windows system with good support for variant rules allowing multiple states and different neighborhoods than Life
Golly: well-engineered open-source cross-platform system for Life-like rules, incorporating hashlife for extremely fast simulation as well as Python scriptability and an extensive pattern library

I'm at a bit of a loss for other systems deserving to be on this list — xlife maybe, as probably the most widely used Unix program, but I don't know of any capability it has that Golly doesn't do better. Suggestions, with justifications for notability? —David Eppstein 20:36, 23 October 2006 (UTC)

The current random assortment of Life-program links is vaguely interesting to look through, but it could certainly stand to be sorted into priority order, at the very least. And I must admit there's no shortage of similar lists of links elsewhere on the Web, so mercilessly truncating this one probably wouldn't hurt. Let's see, if we're aiming for links that a non-Game-of-Life-fanatic might actually follow:

In my book, Alan Hensel's Java applet (from the External Links section) rates a place on the short list of Life programs: it's a really nice clean implementation that lets people explore a lot of carefully documented, impressive Life patterns from a Web browser, _without_ having to download or install (or compile!) anything. -- Well, maybe a Java VM, depending on the browser...
Life32's reputation has gotten a bit tarnished lately, due to things like RLE-header and XOR-pasting bugs in the 2.16 version -- but it still has a number of significant editing features that Golly can't match yet: support for multiple tabbed pages, a drag-and-drop scrapbook, and the ability (shared with MCell) to automate the editor using the language of one's choice.
Xlife is by way of being cross-platform, since there's a solid Windows port available. Unlike Golly, Xlife provides a pure GUI-based method of registering large patterns in terms of (translated, rotated, reflected, rephased) subpatterns... seems somewhat noteworthy, though I don't know for sure that anyone but me has actually _used_ that functionality since about 1995 -- the learning curve is fairly steep!
If Xlife does make the grade, David Bell's much more powerful Life program deserves a mention, too -- macro/command file capabilities, sticky "marks" for subpatterns, multiple undo/redo, cell history ("tracks") like in MCell, and lots of other good stuff. Still don't know this program as well as I should, so I can't say much more.

Dave Greene 07:56, 29 October 2006 (UTC)

I wish Dave Greene's comments had been listened to. The newly revised Life program list ordering is useful only to a Game-of-Life-fanatic (his term). Hensel's Java applet absolutely deserves to be first on the list for the very reasons Greene stated. Rearranging the list would better serve the interests of casual wikipedia users.

Limiting the size of the list to six is needlessly arbitrary. If the list is somewhat properly ordered by relevence to the wikipedia user its size is not so important. Arbitrarily limiting the size of the list removes an element of intelligent choice from the casual wikipedia user.

Half of the entries in the revised external links section don't deserve to be there while the link to the far worthier Callahan's page link has been removed. Restoring the link to Callahan's page and placing it first would better serve the interests of casual wikipedia users.

The recent changes went too far - they deleted too many links. The best interests of the casual wikipedia user have not been served. 66.42.71.38 00:30, 14 January 2007 (UTC)

Y halo thar George Maydwell. Here and in your email you are arguing in the wrong direction — the precise number six is not important, and your emailed complaints that these edits have reduced the web traffic to your site are also not convincing that the reduced traffic is a problem. Based on the half-dozen Google hits I found to "Modern Cellular Automata Author", widespread use will not fly as a reason for your software to be considered notable, either. A better reason (and the one I'll be using to restore the link to your software) is that it can be used to embed CA applets into users' web pages, a very useful functionality that the other programs lack. As for Paul's collection, can you give me a reason why (1) it is significantly more notable than Silver's, Hickerson's, Bell's, Niemiec's, or Koenig's collections, or the collections included withing most of the programs listed, and (2) this page should serve as a directory for such collections? —David Eppstein 01:23, 14 January 2007 (UTC)

A link to the author's easy to use color pattern collection might be more relevant to this article's topic. Web referrals, if true, indicate that at least some casual wikipedia users find a given link to be of interest and potential use (Dave Greene's "...links that a non-Game-of-Life-fanatic might actually follow"). 66.42.71.48 22:30, 14 January 2007 (UTC)

comp.theory.cell-automata contains additional specific discussion.66.42.71.105 14:27, 17 January 2007 (UTC)

It's been a year and a half since I stopped following that one, but does it really have much discussion on Life specifically, as opposed to cellular automata more generally? —David Eppstein 17:20, 17 January 2007 (UTC)

The too many Life program links problem has apparently been mostly solved for now. One remaining issue is the application of the following wikipedia guideline: "... you should give your reader a good summary of the site's contents, and the reasons why this specific website is relevant ...". I opine that including the Life program author names in external program descriptions is by and large not relevant to wikipedia users of the article. If the names were relevant they would appear in the article's text. I propose removal of the names.66.42.71.37 15:56, 20 January 2007 (UTC)

Ok with me. —David Eppstein 17:26, 20 January 2007 (UTC)

[edit] Objects

I hope this isn't in the wrong place...

Does anyone of patterns such as these:

Impassable Wall - A wall is constructed and infinitely extended in both directions. A defined width of the wall is given. If something is created on one side of the wall (outside the width of the wall), it will never be able to reach the other side. i.e. We have glider eaters but such a wall is an everything-eater.
Life in a Life - A unit is created and copied infinitely in a grid with equal spacing which is meant to interact with other units of the same kind in the same way that individual cells interact (23survive3birth145678die). The unit consists of three more or less distinct parts:
- Control center - identifies the state (on or off) of the unit and determines whether to stay alive, become dead, become alive, or stay dead.
- Out messengers - tells the other units' in messengers what the state of the unit is (via gliders?)
- In messengers - receives information from other units' out messengers and tells the control center the state of the surrounding units. 208.124.23.83 00:16, 16 January 2007 (UTC)

It was misplaced at the top of the talk page, but I moved it to the bottom. I don't believe that any impassable wall is known in Life although they can exist in other rules. As for what you call "life in a life", it's often called a "unit cell". See here for an example. If you run Golly, there is a better unit cell (looks like a light or dark square when viewed at high zooms) used in a few of its example patterns, the ones with "META" in their names under "Hashing Examples". —David Eppstein 01:38, 16 January 2007 (UTC)

In Conway's Life the closest known approach to an impassable wall, discussed in this weblog entry, stops only 4/9ths of the gliders shot at it; gliders on the other paths, or the great majority of spaceships on the great majority of paths, will destroy it very quickly.

It seems hard to prove definitively that there's no such thing as an impassable wall in B3/S23 Life -- but I'd definitely prefer to figure out how to break through a given defensive wall, rather than figuring out how to build one! -- Dave Greene 03:08, 20 January 2007 (UTC)

Thanks, although the unit cell linked to is not quite what I had imagined (it is not easy to determine whether the cell is alive or not, also the number of generations that represent one generations is extremely high). It's quite interesting to think about such things. Leon math 01:44, 29 January 2007 (UTC)

The more recent "metapixel" patterns at least fix the "not easy to determine" problem, though unless you have a hashlife-based program such as Golly they are still very slow to run. In the meantime I also found this web link by Dvgrn describing them. (Dave, you could have mentioned this when you posted above!) —David Eppstein 05:16, 29 January 2007 (UTC)

This is my first 3-period space ship:

.....1..........

.111.111........

1......11.......

.11...1..1...1..

...........1111.

...........1...1

.........1..1.1.

..........1.....

Deo Favente (talk) 00:54, 20 February 2008 (UTC)

That's one of the classic c/3 ships -- top spaceship on the left in Golly's Spaceships/c3-orthogonal.rle, for example. Did you find it with an existing search program, or write your own? Dave Greene (talk) 13:57, 28 February 2008 (UTC)

[edit] Thoughts regarding origins and history

Parts of "origins" could perhaps be reworked into a new section "history" by someone more expert and a better writer than myself. My recollection is that Gardner's article was followed in short order by the availability of Life programs on time share dialup systems. A history section would encompass Gardner's article, early time share systems, LIFELINE, early microcomputer implementions, and pattern hunting through the ages up to what experts consider today's current state of the art. A well written history section would provide names, including the names of those who wrote the earliest widely available Life programs.66.42.71.37 00:16, 21 January 2007 (UTC)

[edit] Strongly object to link to the commercial "Fi*e Cellular Automata" site.

This site and its wikipedia link apparently exist primarily to sell copies of the "Fi*e Cellular Automata" software. From the site: "Price and ordering: A single-user license for Fi*e Cellular Automata costs US$16.00, €12.00 or £8.00 (excluding any sales tax).". According to my reading of the wikipedia guidelines the site should NOT be linked to. I also question the relevance of this site to GOL. If q-life is so relevant to the article then why cannot a different NON-COMMERCIAL reference be found and used instead?

Why should wikipedia guidelines against commercial sites be overlooked in this one case? The link has been deleted and reinstated once. Reason was given for the link's removal, but no reason was given for its reinstatement. This is unacceptable.66.42.71.84 21:24, 26 January 2007 (UTC)

Here is a quote from the opening sentence of a press release about the company [[1]]: "... (in business since mid-1997) exists primarily to market the software developed by ...".

Wikipedia article search for the site[[2]] currently returns 55 articles. 66.42.71.95 03:23, 27 January 2007 (UTC)

I repeated your removal of the link from here, and took down a few of the ones from the WP search. There's plenty more left there for others to remove, though. —David Eppstein 05:03, 27 January 2007 (UTC)

Wondered about that link in passing, but left it in because it described how to do the weighting to get Conway's-Life behavior out of q-Life (and I was doing enough for one edit already!). The q-Life rule system seems fairly arbitrary and implementation-specific -- at least, I haven't seen that exact generalization elsewhere in CA literature. Without the link, the paragraph was too vague to be useful, so I rebuilt it with examples from MCell instead. -- Dave Greene 12:12, 28 January 2007 (UTC)

A very similar link was embedded in the text of the Cellular Automaton article. The MCell examples are welcomed. Corresponding GIF files would be cool. Examples of q > 10 state Life exist. 66.42.71.57 19:13, 28 January 2007 (UTC)

[edit] "Variation for two players" section

I just reflexively cleaned up the new two-player-Life section, but now that I'm mostly done, I strongly suspect that the quoted rules aren't particularly encyclopedic. I can find references to two-player "Life" games -- e.g., [P2Life] is mentioned in [several] [places], and there are other implementations [here] and [there] and [everywhere] -- but it looks as if they're significantly different from the rules given here.

The closest I can come is the description of ['war of life'], in which the generation rules are similar (and I like the idea of turning "Conway's Crank" to run the pattern one generation) but there you're only allowed to move one of your cells, not create one of yours and delete one of your opponent's. Is there any documentation of this new two-player variant actually being played, or is it a new invention? I wouldn't mind trying it out, but it would be nice to have an online implementation available, with at least a minor amount of popularity... -- Dave Greene 16:14, 22 May 2007 (UTC)

User Dave Greene wrote on my talk page that this variant is too marginal to be suitable to the main article about this game. So what about creating a stub article "Variants of Conway's Life"? And there could be a section about the two-player variants. What do you think, please?

And the 2-player variant that I described is played by program Lifegen for Widnows 3.11. I can send it to you (with some delay), if you email me at pjel ampers centrum.cz. Pavel Jelinek 19:13, 23 May 2007 (UTC)

My general feeling is that, if it's too marginal for the main page, it's even more too marginal to have its own article, and that one shouldn't make a stub unless there is enough material to later turn it into a full article. That's why Immigration and Quadlife (both similar in principle to the game you describe) were merged into the main article after attempts were made to make separate articles for them. There is a separate article Life-like cellular automaton though it describes a class of CA rules different from what you're talking about here. —David Eppstein 19:27, 23 May 2007 (UTC)

[edit] Vista compatible game of life simulator.

My new computer has Windows Vista, and Life32, which is what I normally use, doesn't work on it. Does anyone know of one that uses Windows Vista? --4.244.141.169

Have you tried Golly? --Zundark 08:36, 5 July 2007 (UTC)

http://kongregate.com/games/locos/the-game-of-life 203.164.96.238 13:35, 31 July 2007 (UTC)

[edit] No infinitely growing pattern

The statement that there are patterns that grow infinitely should be clarified as applying only to an infinite (non existant) universe, where nothing ever goes off the edge or wraps around. Since each cell can have only two states, it should be obvious to anyone that in any real life universe (with or without wrap around) the number of possible configurations is equal to 2ⁿ where n is the number of cells in the universe.

Thus in a 10x10 universe the number of possible configurations is equal to 2¹⁰⁰. Granted, the number is quite large even for a small universe, but it is actually a lot smaller when you consider that many of those configurations will be the same pattern at a different location.

To sum it up, an infinitely growing pattern can exist only in an infinite universe. In a finite universe every pattern will either die, reach equalibrium or lapse into a repeating pattern with a finite number of steps (less than 2ⁿ ).

The comparison of an infinite (non emulatable) universe to a finite universe with wrap around gets into some of the same issues as Euclidean geometry vs non-Euclidean geometry. Just as the notion of a paralell lines never meeting and all convergent lines eventually meeting requires an infinite, non curving universe , so the notion of an infinitely growing life pattern requires an infinite, noncurving universe. Johnelson (talk) 02:36, 18 February 2008 (UTC)

But, mathematically (and if we're not speaking mathematically we should eschew words such as infinite) Life is generally defined on an infinite universe. Many implementations wrap; many others don't (the one I usually use automatically expands the field to fit a growing pattern, and slows to a crawl when the pattern gets too big rather than providing it with an edge to fall off or to wrap around), but we should distinguish what an implementation does from the mathematical definition of the system. —David Eppstein (talk) 07:02, 18 February 2008 (UTC)