Search found 606 matches

by pcallahan
June 11th, 2021, 11:35 am
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

"look at the pattern and delete any wicks and waves you see" That's not very scalable, though, unless you have a way to crowdsource it. And the "crowd" that could provide more signal than noise is going to be extremely small compared to the usual case. I think I'm paraphrasing the same point you ma...
by pcallahan
June 11th, 2021, 10:59 am
Forum: General Discussion
Topic: History Of ConwayLife
Replies: 12
Views: 1783

Re: History Of ConwayLife

This is probably him, from a genealogy page : Charles L Corderman 1924 - 1979 BORN September 10, 1924 DEATH February 4, 1979 LAST KNOWN RESIDENCE Winchester, Middlesex County, Massachusetts 01890 SUMMARY Charles L Corderman was born on September 10, 1924. He died on February 4, 1979 at 54 years old....
by pcallahan
June 10th, 2021, 10:42 am
Forum: General Discussion
Topic: History Of ConwayLife
Replies: 12
Views: 1783

Re: History Of ConwayLife

This was my best match for a topic to post a non-technical question about the people involved in Conway's Game of Life. I have always been curious about Charles Corderman, because unlike other early contributors such as Gosper or Buckingham, I have never heard anything about him besides his list of ...
by pcallahan
June 9th, 2021, 8:23 pm
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

Is lifelib capable of analyzing methuselahs, i.e. given a pattern RLE, can any function output its lifespan, bounding box, MCPS, final population, etc? No. Because ConwayLife is Turing-complete, one can build a Turing machine in it and run an example of why the halting problem has no general soluti...
by pcallahan
June 3rd, 2021, 11:52 pm
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

The new Snarks get built safely behind the existing ones, and then the glider gets sent to knock out the Snarks (at the right time again -- more slightly tricky timing details here, handwave handwave) and the elbow gets pushed a little farther out. The obvious question I've resisted asking: would i...
by pcallahan
June 3rd, 2021, 6:37 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

I knew I've seen something on this topic! https://conwaylife.com/forums/viewtopic.php?f=2&t=1599&p=20210#p20210 You are welcome :) Thanks. This one is good but it does not leave clearance for the return glider. I'm starting to think this will rule out a lot of possibilities. x = 28, y = 22, rule = ...
by pcallahan
June 3rd, 2021, 12:34 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

For that matter, I wonder if it helps to permit period-2, allowing blinkers and toads. This would make the timing a little less general for use as a memory loop but that seems like a problem that can be handled easily at the control end. To follow up on that idea, here is a collision between two gl...
by pcallahan
June 3rd, 2021, 11:19 am
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

It seems like it's definitely going to be cheaper to stick with Spartan-ish stuff for this particular application. Maybe just to set a precise bound on the kind of solution that I'd be happy to see: it should consist of still lifes with a total cell count of 11 or less, and no single still life wit...
by pcallahan
June 2nd, 2021, 8:51 pm
Forum: Patterns
Topic: Thread For Your Useless Discoveries
Replies: 3330
Views: 1347474

Re: Thread For Your Useless Discoveries

Just playing around with gencols. Two gliders hit a loaf. The loaf comes back and sends one glider 90° but also leaves a lot of junk. There might be an easy way to suppress the lower two blocks. x = 22, y = 16, rule = B3/S23 bo$2bo$3o6$9bo$10b2o$9b2o2$19b2o$18bo2bo$18bobo$19bo! Loaf is restored, thi...
by pcallahan
June 2nd, 2021, 7:22 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

The boojum happens to be Spartan. A boojum would be an option for terminating a single-glider extensible memory loop, though I have no idea how it compares to two snarks in terms of construction cost. I'm looking for something much cheaper on the assumption that I'm willing to use 2 outbound glider...
by pcallahan
June 2nd, 2021, 6:23 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Unless I'm forgetting something, the last investigation along these lines was by chris_c (Chris Cain) in 2015, and that was again an investigation looking for 90-degree gliders. So I guess 3 gliders hitting a block is reasonable, unless there is something intrinsically harder about 180°. Keeping th...
by pcallahan
June 2nd, 2021, 4:43 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

To be clear, are the two input gliders allowed to require exact-timing? The examples posted so far allow the gliders to have arbitrary timing. Yes, they are, though my examples did not. That's why I'm optimistic there could be something very simple that works. In fact, using a Python script to gene...
by pcallahan
June 2nd, 2021, 3:57 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

pcallahan wrote:
June 2nd, 2021, 3:53 pm
Another edit: I found a version with two blocks.
Nice! I was hoping to find something like that to post as an example but I gave up. However, I still think there must be something a lot simpler if we include the glider pair spacing and phase shift in the search.
by pcallahan
June 2nd, 2021, 3:53 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

There are quite a few known conduits with tandem-glider inputs, but interest in them has been waning recently. Well, not just recently, I guess, more like for the last decade. No matter how many such things we discover, nobody can really actually find a use for any of them. Well, whether they're us...
by pcallahan
June 2nd, 2021, 2:09 pm
Forum: Patterns
Topic: Simplest 2 gliders in/1 glider out 180° stable reflector?
Replies: 19
Views: 690

Simplest 2 gliders in/1 glider out 180° stable reflector?

There may be an existing thread to cover this, but I was unable to find it. I am curious if anyone has done a search for the pattern described in the subject line. Here's the basic idea: Two gliders traveling in the same direction (not necessarily the same path) hit a stable constellation. Both glid...
by pcallahan
June 1st, 2021, 3:28 pm
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

Heh, really the biggest difference between Gemini and a loopship is that with Gemini, Golly really can't run it quickly (unless you cheat and load it into a Golly timeline, anyway) -- so you're forced to watch it at slow speeds and you can see all the construction details. I think it's also easier ...
by pcallahan
June 1st, 2021, 12:09 am
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

The closest thing we currently have to this kind of technology is the loopship, I think, but that takes glide-symmetry shortcuts again so it's not quite the same. I don't think your link works, but I found it here . Very interesting. It runs much faster in Golly than Gemini. I find it kind of hard ...
by pcallahan
May 31st, 2021, 12:32 pm
Forum: General Discussion
Topic: Thread for basic questions
Replies: 2821
Views: 813460

Re: Thread for basic questions

I finally got a chance to study and think about Gemini after all these years and I had a question that maybe other people have considered or even answered by implementing it. Question The main trick to Gemini (and the reason for its name) is having symmetrical constructors on each end of the glider ...
by pcallahan
May 29th, 2021, 11:15 am
Forum: Patterns
Topic: Oscillator Discussion Thread
Replies: 1941
Views: 830174

Re: Oscillator Discussion Thread

Entity Valkyrie 2 wrote:
May 29th, 2021, 7:17 am
A P218 using it:
This component is really cool! I find it more fun to watch it work as a p654 in which a single glider is tasked with cleaning up its own mess.
by pcallahan
May 28th, 2021, 1:33 pm
Forum: Patterns
Topic: Thread for your unsure discoveries
Replies: 2300
Views: 1188596

Re: Thread for your unsure discoveries

all that is needed is to find a still life that can replace the long barge. Well, OK, but you can say that about any destructive turner . Finding a still life is unlikely, though you might be able to replace it with a spark and find a higher period reflector (I did not look closely enough to guess ...
by pcallahan
May 28th, 2021, 9:59 am
Forum: Patterns
Topic: Thread for your unsure discoveries
Replies: 2300
Views: 1188596

Re: Thread for your unsure discoveries

huh, interesting. weird how it wasn't until 2004 that periodic 180 degree reflectors were made. oh well. Not all of them. It was known in the 1970s that pentadecathlons could reflect gliders 180 degrees. In 1992, Dean Hickerson found that Twin Bees could reflect a glider 180 degrees after first tem...
by pcallahan
May 13th, 2021, 5:56 pm
Forum: The Sandbox
Topic: RLE copy/paste thread - everyone else
Replies: 574
Views: 111672

Re: RLE copy/paste thread - everyone else

Some links for a demo https://www.princeton.edu/news/2020/04/14/mathematician-john-horton-conway-magical-genius-known-inventing-game-life-dies-age #C [[ GPS 3 ]] #C [[ LABEL 40 -6 3 "Some glider collisions (1970s)" ]] #C [[ LABEL 8 47 5 "vanish" ]] #C [[ LABEL 22 45 5 "explode" ]] #C [[ LABEL 39 49 ...
by pcallahan
April 18th, 2021, 9:13 pm
Forum: The Sandbox
Topic: Thread for custom aperiodic (substitution) tilings
Replies: 3
Views: 505

Re: Thread for custom aperiodic (substitution) tilings

My earliest invention was based on marked regular hexagons and Gosper island, which I dubbed "Graphene's dream" due to its resemblance of a partially hydrogenated fragment of graphene mulecules Have you considered making the marks more visible? I am curious how they change over time, but it's hard ...
by pcallahan
April 18th, 2021, 9:01 pm
Forum: General Discussion
Topic: Conway/Guy/Game of Life talk, app *Today*
Replies: 1
Views: 525

Re: Conway/Guy/Game of Life talk, app *Today*

Thanks for the announcement. I almost missed it but remembered at the last minute. On Conway's point in the recorded segment that you learn more by working through the steps manually, I will briefly plug the set of six tiles I posted last year: https://www.conwaylife.com/forums/viewtopic.php?f=7&t=4...
by pcallahan
March 29th, 2021, 10:39 pm
Forum: General Discussion
Topic: Shipibo art and cellular automata
Replies: 4
Views: 3280

Re: Shipibo art and cellular automata

Thanks for re-activating this interesting discussion. I missed it the first time. I sort of doubt that the people who make this art would have ever expressed it in terms of neighborhood constraints, and their designs include global symmetry as well that would not arise from those rules. At the same ...