Search found 508 matches

by pcallahan
May 18th, 2020, 5:17 pm
Forum: General Discussion
Topic: John Conway has passed away
Replies: 10
Views: 1241

Re: John Conway has passed away

NYT had an article about Conway by his biographer Siobhan Roberts. The emphasis is on contributions other than Game of Life, but it's quite interesting. I had forgotten about the game Sprouts for many years. I remember that it was featured in the Piers Anthony novel Macroscope. I have never played. ...
by pcallahan
May 11th, 2020, 2:00 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

I have added a new printable tile sheet to https://drive.google.com/drive/folders/1KIOs3y7xN0f6PSrAKULJsUq6ojGtD8Tq?usp=sharing (As always, I would advise testing that the printer is not cutting of boundaries before using a magnetic sheet.) I haven't printed them yet, but I will soon unless I think ...
by pcallahan
May 4th, 2020, 6:07 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

A while back, used to do something similar to this where I'd copy-paste-rotate-overlap tiles similar to these, and color-match parts in order to construct SLs. Its super time-consuming and I don't know its applicability. https://i.postimg.cc/2yrN03Mt/EX.png That's an interesting approach. I think t...
by pcallahan
April 29th, 2020, 11:21 am
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

Here's what the redesigned tiles (split petals) look like after printing on magnetic sheets and cutting. The split petals and leaves span a longer boundary than the the dots, and are, I think a little more forgiving in terms on placement. 20200429_073003.jpg I pu PDFs of both types of tiles in this ...
by pcallahan
April 27th, 2020, 1:54 pm
Forum: General Discussion
Topic: John Conway tribute project (FPGA full HD GoL)
Replies: 3
Views: 348

Re: John Conway tribute project (FPGA full HD GoL)

It is just a for-fun and tribute project, wasn't aiming for high speed as 1080p @ 60 is still the ceiling with most monitors nowadays. It is an *as simple as it goes* implementation that calculates the entire grid. I know people here have much more background on GoL and implementations so this may ...
by pcallahan
April 27th, 2020, 12:30 pm
Forum: General Discussion
Topic: John Conway tribute project (FPGA full HD GoL)
Replies: 3
Views: 348

Re: John Conway tribute project (FPGA full HD GoL)

Do you have more information on the FPGA? I think the implementation itself is the interesting part here rather than raw speed. High speeds can be attained using algorithms like HashLife rather than optimizing the speed of calculating individual cell transitions. Is this a sparse implementation, i.e...
by pcallahan
April 26th, 2020, 10:54 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

Kiran wrote:
April 26th, 2020, 10:04 pm
The only place this graph can have an intersection is at the vertex between four cells, and that can only happen if all four cells around that vertex are occupied.
Yeah, I realize that. I had never given it much thought before.
by pcallahan
April 26th, 2020, 5:37 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

This latest image is too busy. The second image of the earlier posting is better. The split petals give the impression of "magnetic lines of force", which the first petals image doesn't have, even though I understand what the petals are showing. I agree with both points. I also like the petals, tho...
by pcallahan
April 26th, 2020, 4:14 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

One more thought. Here's a tiling that presents a very direct view of the skeleton of connected dots. It's no-nonsense compared to the petals and leaves. However, I think it is still a lot harder to pick out births visually. Maybe I should not fully connect the blue lines. Screen Shot 2020-04-26 at ...
by pcallahan
April 25th, 2020, 11:51 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 15
Views: 2677

Re: Tiling with placement rules for still life and p2 oscillators

I was getting a little bored with the minimalist look of the tiles above and decided to try to do something with colors and a "petals and leaves" theme. Personally, I find it easier to spot triples (particularly unwanted ones) when they look like leaf clusters or flowers. I have made a number of mis...
by pcallahan
April 16th, 2020, 12:45 am
Forum: General Discussion
Topic: Realizing CGOL rules in mechanical unit
Replies: 29
Views: 16548

Re: Realizing CGOL rules in mechanical unit

Replying to my own post from 2016. I do think water is interesting, I also see the point of no moving parts (saving state in some container). I also think it's possible and can use tricks from electronics which is nice. On the other hand I can't find anything like it on the net. No logic gates or ad...
by pcallahan
April 15th, 2020, 1:06 am
Forum: Website Discussion
Topic: John Horton Conway
Replies: 26
Views: 1894

Re: John Horton Conway

Basically, there are plenty of allowable variables -- length of leg, length of body, size and shape of head, length and shape of arms -- so that a little experimenting was pretty much certain to be able to get a clean glider out, somehow. A northbound LWSS might have been a bit more of a challenge....
by pcallahan
April 14th, 2020, 9:33 pm
Forum: General Discussion
Topic: John Conway has passed away
Replies: 10
Views: 1241

Re: John Conway has passed away

Princeton finally has an obituary out. https://www.princeton.edu/news/2020/04/ ... e-dies-age
by pcallahan
April 13th, 2020, 3:37 pm
Forum: Website Discussion
Topic: John Horton Conway
Replies: 26
Views: 1894

Re: John Horton Conway

In a number of areas, including cellular automata, he didn't do either the first work or the final work, but an important intermediate step that made it more interesting and accessible to the rest of us. That's probably true. He conveyed a playfulness that I think most mathematicians appreciate, bu...
by pcallahan
April 12th, 2020, 6:25 pm
Forum: General Discussion
Topic: John Conway has passed away
Replies: 10
Views: 1241

Re: John Conway has passed away

Freywa wrote:
April 12th, 2020, 6:14 pm
I am not mourning the death. I am not at all saddened by the fact that it was from Covid-19.
Well, I am mourning his passing. 82 is not old today, though it is true he was in very poor health to begin with. Perhaps it was a swift and merciful end. Anyway, I don't get a say in that.
by pcallahan
April 12th, 2020, 6:19 pm
Forum: Website Discussion
Topic: John Horton Conway
Replies: 26
Views: 1894

Re: John Horton Conway

Words fail me, the impact his work had on my life is beyond measure. Jon Bennett (Xlife) Here's a local obituary (actually found by simsim314) https://dailyvoice.com/new-jersey/mercer/obituaries/covid-19-kills-renowned-princeton-mathematician-game-of-life-inventor-john-conway-in-3-days/786461/?fbcl...
by pcallahan
April 12th, 2020, 12:44 pm
Forum: General Discussion
Topic: John Conway has passed away
Replies: 10
Views: 1241

Re: John Conway has passed away

According to several sources close to his family, John Horton Conway died today of an illness related to the COVID pandemic. All I can say in this sad moment is that I am happy to know that his legacy will live on through us. (Aside) I am also angry at any needless deaths caused by our delayed resp...
by pcallahan
April 11th, 2020, 4:50 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

It's exponential at first, then there is a very long tail. If you have family member in risk group, I would worry more about the tail rather than the exponential part. When we stop the exponent we actually prolong the tail, making this period last a year or two up to vaccine. I've no good solution ...
by pcallahan
April 2nd, 2020, 12:41 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

I hope nobody finds my fixation morbid. I also repeat that I am not an epidemiologist and I have no idea what is needed for a realistic pandemic model, but I can get similar curves with these assumptions to what I see in actual data online. This time I decided that instead of going straight to calcu...
by pcallahan
April 1st, 2020, 3:20 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

I should probably read how real epidemiologists do this, but I put together a simple model that at least qualitatively captures the curve-flattening process. Instead of trying to separate out the spread factor and the percent detected, as I did in https://conwaylife.com/forums/viewtopic.php?f=12&t=4...
by pcallahan
March 28th, 2020, 3:23 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

first global incident ( financial panic ) 1857 ( shortly after Crystal Palace Exhibition, London, 1850 ) the interesting $3 Trillion response begs the question of when will people realize that we are not going back to "the way things were before" even though it may sure feel like it, for a while......
by pcallahan
March 28th, 2020, 12:22 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

I'm also believing corona will continue for half a year so new economical opportunities with the internet technologies should come up, as the market always adapts to new situation. If free market is trying to emulate evolution, so now it's the time when the meteor hits. It may last until a vaccine ...
by pcallahan
March 27th, 2020, 2:54 am
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

The toilet paper is to throw at the rampaging zombies as they approach to eat your brains. Zombies are pretty vulnerable. You just have to hit them square in the noggin with one of those rolls. The paper towels are for the big zombies.
by pcallahan
March 26th, 2020, 2:11 am
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

A random thought that might have been better for US Pi Day: "The SARS-CoV-2 genome ... is an RNA molecule of about 30,000 bases containing 15 genes" . The world record for memorizing digits of pi is 67890 . Others have memorized 30000 or more digits. The bases A, U, C, and G are as easy to memorize ...
by pcallahan
March 24th, 2020, 11:47 pm
Forum: The Sandbox
Topic: COVID-19
Replies: 73
Views: 2979

Re: COVID-19

Though I don't quite believe it, total cases in the US seem to be on a linear, not exponential growth path over the last few days: https://www.worldometers.info/coronavirus/country/us/ New York is also taking the brunt of it now. There could be all kinds of artifacts skewing the data, but maybe the ...