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Thread for homepage article suggestions/contributions

Post by dvgrn » June 7th, 2020, 10:51 am

A lot of interesting stuff has happened since January, but the discovery of the Scholar is still what’s showing up on the conwaylife.com home page.

I’d like to put something new there every month, or even every week, but I’m not likely to actually write 52 new articles a year, or even 12 of them. Could really use some help with this.

If current-news articles show up here as posts on this thread, with or without extra decorations like images or LifeViewer animations, I can take care of making them show up on the home page.

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » June 11th, 2020, 10:13 am

dvgrn wrote:
June 7th, 2020, 10:51 am
A lot of interesting stuff has happened since January, but the discovery of the Scholar is still what’s showing up on the conwaylife.com home page.
To be a little more specific, here's what has showed up in LifeWiki CurrentNews since the scholar:
June 8: A collaborative effort produces a fully universal *WSS-to-glider converter that recovers in only 588 ticks, and works even if moved by an odd number of cells along the input lane.
June 7: Matthias Merzenich completes an adjustable-width c/5 orthogonal wickstretcher using components by Keith Amling and Hartmut Holzwart.
June 5: Entity Valkyrie completes a mechanism suggested by Martin Grant to make a Bandersnatch, a glider-constructible color-changing glider shifter with a recovery time of only 70 ticks.
May 25: Louis-François Handfield and Goldtiger997 find improved highway robbers with better clearance and 876- and 873-tick recovery times.
May 22: Entity Valkyrie constructs a gun for 58P5H1V1, the first gun to produce a c/5 diagonal spaceship.
May 9: The silverfish, a self-supporting 31c/240 caterpillar-type spaceship designed using the slow salvo recipe from the Centipede but a simpler front end, is completed.
May 6: Goldtiger997 solves the problem of glider-constructing all pseudo still lifes consisting of 4×N chunks of blocks agar.
May 3-4: Louis-François Handfield adapts Martin Grant's new HL161H conduit to make a new compact color-changing edge shooter, HSW47T214.
Apr. 21: Rob Liston discovers 49768M, the longest-lasting known methuselah fitting within a 16×16 bounding box.
Apr. 11: John Horton Conway, the inventor of Conway's Game of Life, dies in Princeton, NJ at the age of 82.
Apr. 3: Goldtiger997, Tanner Jacobi, and others complete the glider synthesis for 58P5H1V1, the first synthesis for a c/5 diagonal spaceship.
Apr. 1: A loafer appears for the first time in an asymmetric soup, submitted to Catagolue by John Goodman. Coincidentally, this occurred exactly two years after Dave Greene posted a fake soup for April Fools' Day 2018.
Mar. 25: Martin Grant and others complete the glider synthesis for 56P6H1V0, the first synthesis for a c/6 orthogonal spaceship and the first for a period-6 spaceship.
Mar. 22: Andrew J. Wade uses life_slice_ship_search to find 186P7H2V0, a third 2c/7 orthogonal spaceship, part of an infinite family based on a known 2c/7 wave.
Mar. 22: Goldtiger997 completes the activation stage for a recipe for 56P6H1V0, which along with the spider and weekender is now one of the largest elementary spaceships for which a glider synthesis can (presumably) be completed.
Mar. 17: Andrew J. Wade discovers 409P6H1V0, the narrowest known c/6 orthogonal spaceship, using life_slice_ship_search.
Mar. 9: Richard K. Guy, discoverer of the glider, passes away at the age of 103.
Feb. 9: Rob Liston discovers a new p16 oscillator, Rob's p16, using apgsearch. It is the smallest known p16 by both population and bounding box, the first p16 to appear from an asymmetric soup, the first strictly volatile p16, and the first new rotor to be discovered by asymmetric soup search since the 1980s.
Feb. 8: All 19-bit still lifes are confirmed to have valid glider syntheses.
Jan. 26: Dave Greene creates LifeSuper, an extended version of LifeHistory for advanced pattern annotation.
Jan. 26: Entity Valkyrie constructs a period-11040 spider gun, the first gun to fire a c/5 orthogonal spaceship.
Jan. 13: Matthias Merzenich sets up a new "manually distributed" search (table here), to find out whether a symmetric c/8 spaceship exists at width 19.
Jan. 9: Nathaniel Johnston completes a long-running enumeration of 34-bit still lifes, finding 35,422,864,104 strict still lifes with 34 bits, and 41,058,173,683 pseudo still lifes with the same bit count, including 26 triple pseudo still lifes.
Jan. 5: A Rules namespace update on the LifeWiki allows LifeViewer to display in-browser many patterns using rule tables and trees, which previously couldn't be simulated without copying them into Golly.
I'll probably go ahead and make a post for all the green circuitry stuff. If anyone wants to put together articles for things that happened mostly before that recent green group, now would be a good time. There's some spaceship discovery stuff (orange), some Stuff Found Floating In Soup (purple) and some glider synthesis stuff (blue).
Last edited by calcyman on June 11th, 2020, 1:04 pm, edited 1 time in total.
Reason: Colour code was incorrect for 19-bit still life synthesis announcement

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Re: Thread for homepage article suggestions/contributions

Post by Hunting » June 26th, 2020, 9:03 pm

I might write something at some point to advertise my blog.
中国共产党万岁!!!!
Support Taliban!
STOP THE ATROCITY

LeapLife - DirtyLife - LispLife

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » July 2nd, 2020, 12:45 pm

Here's a LifeViewer-based summary of this spring's 58P5H1V1 synthesis that Saka sent to me privately back in April. For some reason I didn't get around to editing for publication then, and it got buried by other projects on my LIFO stack. Working on it now:

Code: Select all

x = 536, y = 536, rule = B3/S23
504bobo$504b2o$505bo2$503bo$501b2o$502b2o5bobo$17bo491b2o$18bo491bo$
16b3o$492bo20bobo$491bo21b2o8bobo$491b3o20bo8b2o$20bo503bo$5bobo13b2o$
6b2o12b2o$6bo2$4bo510bo$2bobo509bo$3b2o10bobo496b3o8bo$9bo6b2o505b2o$
10b2o4bo507b2o$9b2o$529bo$527b2o$493bobo32b2o$481bobo9b2o$481b2o11bo$
482bo52bo$533b2o$56bo430bobo44b2o$54bobo430b2o40bobo$55b2o431bo40b2o$
530bo$62bo$63bo$61b3o$487bo$486bo$486b3o20bo$463bobo41b2o$463b2o43b2o
13bo$464bo58bobo$523b2o$67bo$68bo435bo$66b3o426bo6b2o$470bo24bobo5b2o$
31bo438bobo22b2o$32b2o436b2o$31b2o$508bo$506b2o$74bo432b2o$75bo$73b3o$
461bo$461bobo$461b2o4$81bo404bo$82bo402bo$80b3o402b3o$452bo$452bobo$
436bo15b2o$434b2o$426bobo6b2o57bo$426b2o64b2o$427bo49bo15b2o$73bo402bo
$74bo401b3o$72b3o351bo$425bo$425b3o2$61bo$59bobo$60b2o406bo$467bo$65bo
bo399b3o$66b2o3bo$66bo5bo6bo$70b3o7b2o$79b2o9$408bo$407bo$400bobo4b3o$
114bo285b2o63bobo$115bo285bo63b2o$113b3o350bo6$465bo$458bo4b2o$458bobo
3b2o$458b2o5$394bobo$123bo270b2o$124b2o269bo$123b2o$136bo$137bo$135b3o
$398bo$397bo$397b3o$134bobo$135b2o300bo$135bo301bobo$437b2o$134bo$135b
o$133b3o$385bo$384bo52bo$384b3o48b2o$436b2o$380bo30bo$373bo4b2o31bobo$
371b2o6b2o30b2o$141bo230b2o46bo$139bobo276b2o$140b2o277b2o$372bo$129bo
bo240bobo$130b2o240b2o$130bo4$363bo37bo$140bo222bobo35bobo$141b2o27bo
192b2o36b2o$140b2o29b2o$170b2o6$382bo$382bobo$382b2o11$196bo$197b2o$
196b2o4$364bo$348bo15bobo$348bobo13b2o$348b2o10$195bo$196b2o134bobo25b
o$195b2o135b2o26bobo$333bo26b2o2$196bo$194bobo$195b2o$178bo21bobo151bo
bo2bo$176bobo22b2o151b2o3bobo$177b2o22bo141bo11bo3b2o$341b2o$342b2o10$
205bo$203bobo$204b2o2$212bo$213b2o$212b2o103$214bo$197b2o15b2o$198b2o
7b3o3bobo$197bo11bo136b3o$208bo137bo$320b2o25bo$319b2o$321bo3$320b3o$
320bo14b2o$182bo138bo12b2o$182b2o152bo$181bobo27bo$211b2o$210bobo130bo
$337b3o2b2o$337bo4bobo$338bo15$346b2o10bo$185b3o158bobo8b2o$187bo158bo
10bobo$186bo$181b2o$180bobo195bo$182bo7b2o185b2o$189bobo185bobo$191bo
2$178b3o203b3o$180bo172b3o23bo4bo$179bo173bo24b2o5bo$354bo23bobo12$
134b2o$135b2o$134bo2$140bo$140b2o$139bobo3$136b2o$137b2o$98b2o31bo4bo$
97bobo31b2o$99bo30bobo239b2o$371b2o$373bo2$414b2o$409b2o3bobo$404b2o2b
2o4bo$404bobo3bo$404bo8$418bo$417b2o$417bobo8$434b2o$434bobo$434bo14$
141b3o$143bo$142bo$78b3o$80bo$79bo2$75bo$75b2o$65b2o7bobo$64bobo$66bo
3$69bo$69b2o$68bobo$470b2o$449bo20bobo$95b2o351b2o20bo$94bobo351bobo$
96bo2$90b2o$91b2o386b2o$90bo369b2o17bobo$460bobo16bo$449b2o9bo$449bobo
$83b2o364bo$84b2o$83bo404b2o$451b2o35bobo$88b3o359b2o36bo$90bo361bo$
89bo$498b2o$498bobo$454b3o41bo$454bo$455bo3$502b3o$502bo$503bo2$28b2o$
27bobo$29bo7$15b2o$bo12bobo$b2o13bo$obo8bo$11b2o$10bobo4$2b2o$3b2o480b
o$2bo481b2o$484bobo2$8b2o40b3o$9b2o41bo$8bo42bo5$12b3o506bo$14bo505b2o
$13bo4b2o500bobo$17bobo$19bo506b2o$514b2o10bobo$41b3o469b2o11bo$43bo
471bo$21b2o19bo$20bobo$22bo15b2o$39b2o472bo$28bo9bo473b2o$28b2o482bobo
$27bobo$520b2o$519b2o$521bo$515b3o$515bo$40b2o474bo$41b2o$40bo!
[[
WIDTH 720
AUTOSTART
GPS 20
PAUSE 2 "58P5H1V1 Synthesis"
PAUSE 2 "By Kazyan (Tanner Jacobi)\nand Goldtiger997"
PAUSE 2 "The synthesis was posted \non the forums on April 3, 2020."
T 60 "At the time this animation was made,\nit cost 161 gliders."
T 139 "It has since been reduced to 100 gliders."
GPS 30 T 202 "Let's zoom in."
ZOOM 12 GPS 60
T 203 PAUSE 3 "First glider collision."
T 216 PAUSE 3 "Beehive at beehive made."
PAUSE 2 "This will become the 'centerpiece'\nof the consttruction."
T 455 "A complex seed constellation is gradually\nbuilt up around the beehive at beehive."
T 456 PAUSE 3 "OK, that last part was cool.\nIt will happen again on the other side."
X -12
PAUSE 2 "11 cells are added all at once."
T 485 "\n"
GPS 30 "Magic..."
T 550 X 0
T 599  X 10 Y -10 "More of the superstructure is\nincrementally constructed."
T 600 PAUSE 3 "See those 2 long barges? \n They're going to get extended 4 times."
T 872 "\n"
T 873 PAUSE 3 "...And now they're boats, I guess. \n (Barges are a type of boat, right?)"
PAUSE 1 X 0 Y 0
T 936 PAUSE 3 "Here comes the really fun part!" ZOOM 5.5
PAUSE 2 "Hope you don't mind some SFX..."
PAUSE 0.5 LAYERS 10 DEPTH 2 THEME Fire
PAUSE 0.5 ZOOM 1 ANGLE 45 T 945
PAUSE 1 T 960 ZOOM 7.7 ANGLE 0 THEME Poison LAYERS 1
T 1000 "And the ship is done!"
T 1094 "Wait, don't forget cleanup!" THEME Blues X -6 Y 3
T 1100 PAUSE 3 X 25 Y -25 "The construction is complete!" ZOOM 15
LOOP 1500
]]
#C By: Saka

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Re: Thread for homepage article suggestions/contributions

Post by Andrew » July 2nd, 2020, 9:51 pm

Very impressive! And a tribute to the great work Chris has been doing.
(Almost makes me want to write a LifeViewer-script-to-overlay-script converter so I can watch the same sort of things in Golly. Almost...)

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » July 2nd, 2020, 10:06 pm

Andrew wrote:
July 2nd, 2020, 9:51 pm
Very impressive! And a tribute to the great work Chris has been doing.
(Almost makes me want to write a LifeViewer-script-to-overlay-script converter so I can watch the same sort of things in Golly. Almost...)
No need, I think. Chris has already checked in showinviewer.lua for the next build of Golly, or it works fine in v3.3.

The waypoint commands that make the above animation work are just plain RLE comments, and now Golly scripts have easy access to those comments, so they can build an appropriate LifeViewer HTML page and then open it in the OS's default browser.

I mean, I guess it doesn't exactly count as "in Golly", but it seems close enough for me!

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Re: Thread for homepage article suggestions/contributions

Post by Andrew » July 2nd, 2020, 11:58 pm

dvgrn wrote:
July 2nd, 2020, 10:06 pm
No need, I think. Chris has already checked in showinviewer.lua for the next build of Golly, or it works fine in v3.3.
I guess I prefer to stay in Golly because I'm more familiar with its keyboard shortcuts (it'd be nice if LifeViewer had configurable hot keys but that's probably asking for too much!). While I think of it, is there any way to put LifeViewer in full screen mode? I scrolled thru the help but didn't see any key combo that does it.

Actually, now that we have showinviewer.lua, is there any point keeping lifeviewer.lua in the distribution? The latter's script support is no longer compatible, so you get weird errors if you try and run lifeviewer.lua after loading a pattern like yours. I got a message saying "58P5H1V1 unknown script command". I don't see much point keeping lifeviewer.lua if its script support is out of sync with the LifeViewer plugin.

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Re: Thread for homepage article suggestions/contributions

Post by rowett » July 3rd, 2020, 1:12 am

Andrew wrote:
July 2nd, 2020, 11:58 pm
... it'd be nice if LifeViewer had configurable hot keys but that's probably asking for too much!
I'll put it on the backlog. It's part of a bigger piece of work around user preferences (that I've not got to yet).
Andrew wrote:
July 2nd, 2020, 11:58 pm
While I think of it, is there any way to put LifeViewer in full screen mode?
Not currently. The best you can do at the moment is use the [[ WIDTH ]] and [[ HEIGHT ]] (or [[ POPUPWIDTH ]] and [[ POPUPHEIGHT ]]) script commands to make the LifeViewer canvas larger. If you're using showinviewer.lua then you can always edit the script to increase the default LifeViewer window size:

Code: Select all

-- width and height of the LifeViewer canvas in pixels
local viewerwidth = 800
local viewerheight = 700
Andrew wrote:
July 2nd, 2020, 11:58 pm
Actually, now that we have showinviewer.lua, is there any point keeping lifeviewer.lua in the distribution?
No point now. It can be removed.

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Re: Thread for homepage article suggestions/contributions

Post by Andrew » July 3rd, 2020, 3:54 am

rowett wrote:
July 3rd, 2020, 1:12 am
No point now. It can be removed.
Ok, I'll do that soon, but it seems a shame to waste all that work. I'll also remove lifeviewer.html and the images it uses from Help. (Maybe you could re-use all those nice docs somehow -- eg. maybe LifeViewer could have a button or key that links to a revamped version of lifeviewer.html? That would allow people to read a much more detailed description of the scripting commands, hot keys, etc.)

I searched the Patterns folder and there's only one file with scripting commands for lifeviewer.lua.
At the bottom of Life/Rakes/c2-Cordership-rake.rle are these 2 lines:

Code: Select all

#C Script commands for lifeviewer.lua:
#C [[ AUTOSTART AUTOFIT HISTORYFIT THEME 4 ANGLE 10 STEP 8 PAUSE 2 STARS ]]
The commands don't quite work the same when showinviewer.lua is run (I don't see any stars) so should I remove those lines? Or just let me know the new syntax and I'll update the file.

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » July 3rd, 2020, 9:20 am

Andrew wrote:
July 3rd, 2020, 3:54 am
The commands don't quite work the same when showinviewer.lua is run (I don't see any stars) so should I remove those lines? Or just let me know the new syntax and I'll update the file.
Just an ordering problem -- a change in the way a series of waypoint commands is interpreted, if I remember right. This should work:

#C [[ STARS AUTOSTART AUTOFIT HISTORYFIT THEME 4 ANGLE 10 STEP 8 PAUSE 2 LOOP 7500 ]]

The LOOP 7500 just avoids showcasing the impressive mess that happens when the Cordership hits the edge of LifeViewer's universe.

A lot of Golly's patterns could really benefit from a few LifeViewer labels, and/or arrows, polylines, shaded regions, timed captions, TRACK or TRACKLOOP settings, etc. They're not that hard to do, one pattern at a time, but building up a significant number of them would be a big project.

If anyone on the forums wants to collaborate to generate LifeViewer comments for Golly patterns, please say so and I'll start a new thread to collect contributions.

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Re: Thread for homepage article suggestions/contributions

Post by Andrew » July 3rd, 2020, 9:38 pm

dvgrn wrote:
July 3rd, 2020, 9:20 am
#C [[ STARS AUTOSTART AUTOFIT HISTORYFIT THEME 4 ANGLE 10 STEP 8 PAUSE 2 LOOP 7500 ]]
That worked -- thanks. I've now removed lifeviewer.lua and related files from the golly repository. I've put them all in a zip file on my website in case anybody wants to get them in future:

http://www.trevorrow.com/golly/lifeviewer.zip

I made minor changes to lifeviewer.lua so it can find the html/png files included in the zip.

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » August 16th, 2021, 10:24 am

I've added a new discussion topic to the LifeWiki Tiki bar, because I'd like to set up a place on the wiki where people can easily write collaborative "popular" articles on various topics. It seems as if a LifeWiki page would be a good scratch pad for this kind of thing, due to the availability of LifeViewer for roughing out illustrations and so forth. Eventually the articles could be converted into home-page blog posts -- or could be linked to directly from other places, converted into PDF or other formats, or whatever.

In point of fact, I'm bringing this up because some academic contacts in India have asked me to contribute a chapter or three to a book they're putting together to be published by Springer, based on a lecture series earlier this year. The title of the book will apparently be

"The Mathematical Artist: A Tribute to John Horton Conway"

Here are the people leading the "Cellular Automata in India Research Group" that put the lecture series together, and now the book proposal:

Dr. Kamalika Bhattacharjee, Assistant Professor, Department of Computer Science and Engineering,
National Institute of Technology, Tiruchirappalli, Tamilnadu, India
Dr. Sukanta Das, Associate Professor and Head, Department of Information Technology,
Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India

Three Possible Articles To Start With
* stable infinite line crosser and double-line (barge) crosser

* glider recipes for a series of increasingly larger "greyship" spaceships (see the first two entries in this list)

* self-synthesizing oblique loopship

These are mostly not my own projects; I didn't really do very much work on any of them, except maybe the stable line crosser (and even then I didn't contribute the recipes, which are the important part). It would make sense to me to do the article-writing collaboratively, if possible, similar to the spirit of the original projects -- and if this book project works out, basically get as many conwaylife.com community members into the chapter co-authors list as want to be there.

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Re: Thread for homepage article suggestions/contributions

Post by MathAndCode » August 16th, 2021, 7:00 pm

dvgrn wrote:
August 16th, 2021, 10:24 am
In point of fact, I'm bringing this up because some academic contacts in India have asked me to contribute a chapter or three to a book they're putting together to be published by Springer, based on a lecture series earlier this year. The title of the book will apparently be

"The Mathematical Artist: A Tribute to John Horton Conway"

Here are the people leading the "Cellular Automata in India Research Group" that put the lecture series together, and now the book proposal:

Dr. Kamalika Bhattacharjee, Assistant Professor, Department of Computer Science and Engineering,
National Institute of Technology, Tiruchirappalli, Tamilnadu, India
Dr. Sukanta Das, Associate Professor and Head, Department of Information Technology,
Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India

Three Possible Articles To Start With
* stable infinite line crosser and double-line (barge) crosser

* glider recipes for a series of increasingly larger "greyship" spaceships (see the first two entries in this list)

* self-synthesizing oblique loopship
While these seem like good topics for the news section, I don't think that they would be good topics for chapters in a book that is not specifically geared towards people with extensive prior knowledge of Conway's Game of Life. I think that for the book, it would best to break the complex projects up into chapters about their simpler parts. For the infinite line crosser and infinite barge crossed, the simpler parts are synthesis components (which fall under glider syntheses) and circuitry. The greyship syntheses can be reduced to glider syntheses, and the self-synthesizing oblique loopship can be reduced to circuitry and salvo construction.
Of course, merely explaining these concepts would seem boring and likely useless to the readers, so at the end of each chapter, let's apply the concept just explained to one of the discoveries that you mentioned. This suggests an order of syntheses (with the greyship synthesis at the end) first, circuitry (with the infinite line crosser and infinite barge crosser at the end) second, and salvo construction (with the self-synthesizing oblique loopship at the end) last. Because the chapter about glider syntheses is the first chapter about Conway's Game of Life, it will also have to introduce Conway's Game of Life then transition to glider syntheses. Here is a first attempt:
In the late 1960s, John Conway decided to explore a certain type of cellular automaton. Specifically, he would explore cellular automata that:
  • took place on a grid of squares with four squares meeting at each corner
  • had two states (alive and dead) so that each square had to have one of those two states (although it could change from one to the other)
  • had all squares repeatedly update their states simultaneously
  • gave each square a "neighborhood" (the set of other squares that could directly affect that square) consisting of the squares with which it shared an edge or a corner (or, in technical terms, the range-1 Moore neighborhood)
  • had each square choose a new state based on its current state and the number of squares in its neighborhood that are currently on but not their arrangement (or, in technical terms, is outer-totalistic)
Conway wanted to find such an automaton that would have certain interesting properties, such as not making every pattern result in an explosion. (This ruled out birth with one live neighbor.) Eventually, Conway settled on a rule where for each update, each square is alive for the next generation if and only if it satisfies one of the two criteria:
  • The square has three live neighbors.
  • The square is already alive and has two live neighbors.
Conway chose this rule partially because it allows a lot of interesting patterns. Here is one such interesting pattern:

Code: Select all

x = 3, y = 3, rule = B3/S23
2bo$2o$b2o!
[[ THUMBNAIL VIEWONLY ZOOM 64 THEME 6 GRID ]]
After one update, it has the following form:

Code: Select all

x = 3, y = 3, rule = B3/S23
bo$o$3o!
[[ THUMBNAIL VIEWONLY ZOOM 64 THEME 6 GRID ]]
After a second update, it has the same shape as originally, but it has been glide-reflected (due to which it is called the glider). Because all squares follow the same rules, and a square's next state does not depend on the arrangement of the alive squares in its neighborhood, this mirror image behaves the same way as the original, returning to the original orientation after two more updates. After four updates, the glider has returned to its original orientation but has moved one row down and one cell to the left. The glider will keep moving down and to the left as long as the grid keeps updating. This type of pattern (that periodically returns to its initial state and orientation but in a different position) is called a spaceship.
One usage of gliders is to make other objects. For example, two gliders colliding in a certain way make an object called a fishhook.

Code: Select all

x = 8, y = 5, rule = B3/S23
obo$b2o$bo3bo$5bobo$5b2o!
[[ THUMBNAIL VIEWONLY ZOOM 64 THEME 6 GRID ]]
A fishhook consistently has seven live cells, and their positions do not change. This type of pattern (that never changes) is called a still-life. The fishhook is a particularly useful still life because it can "eat" gliders, i.e. destroy gliders without being permanently changed.

Code: Select all

x = 8, y = 7, rule = B3/S23
obo$b2o$bo$4b2o$4bobo$6bo$6b2o!
[[ THUMBNAIL VIEWONLY ZOOM 64 THEME 6 GRID ]]
While some still-lives, like a fishhook, can be made from a single collision of two or more gliders, the feasibility of this gradually decreases as the size of the still-life increases. The only way to build large still-lives with gliders is to build them up gradually from a still-life that is small enough to form directly from a glider collision. This is achieved via converters, which are ways to change a still-life in a specific way by hitting it with a particular arrangement of gliders. As an example, here is a way to add a conjoined fishhook to the tail of a fishhook so that it can eat gliders from two directions:

Code: Select all

x = 12, y = 9, rule = B3/S23
2o$obo$2bo$2b2o2$5b2o$4bobo2bo$6bo2bobo$9b2o!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 40 THEME 6 GRID ]]
Here is an example of a converter that makes turns a fishhook into a much large still-life (as well as leaving behind an extra object that can be deleted with one additional glider):

Code: Select all

x = 17, y = 5, rule = B3/S23
2o13bo$obo11bobo$2bo7b2o2bobo$2b2o5bobo3bo$11bo!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 48 THEME 6 GRID ]]
This converter requires an additional still-life (called a beehive) that can be placed beforehand with two gliders.

Code: Select all

x = 21, y = 7, rule = B3/S23
17bo$2o13b2o$obo13b2o$2bo$2b2o15b2o$18b2o$20bo!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 36 THEME 6 GRID ]]
Thus, this converter has three stages: one preparatory stage to place the beehive, one stage that does the actual conversion, and one stage to clean up an unwanted object. Some but not all converters require preparatory or cleanup stages.
Similarly to how small still-lives but not large still-lives can result from a glider collision, small spaceships but not large spaceships can be made from gliders in a single step. Here is an example of three gliders making a small spaceship:

Code: Select all

x = 12, y = 7, rule = B3/S23
bo$2bo3bobo$3o3b2o$7bo$10bo$9b2o$9bobo!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 52 THEME 6 GRID X -1 ]]
However, large spaceships must be made by converting a specially-designed still-life into a spaceship. Here is an example of one such spaceship:

Code: Select all

x = 41, y = 28, rule = B3/S23
16b3o3b3o$15bo2bo3bo2bo$18bo3bo$14bo3bo3bo3bo$14bo3bo3bo3bo$18bo3bo$18b
o3bo2$16b3o3b3o$17bo5bo$17b7o$16bo7bo$15b11o$14bo11bo$13b15o$12bo15bo
$11b19o$10bo19bo$3o6b23o6b3o$o2bo4bo23bo4bo2bo$o6b27o6bo$o3bobo11bobo
bo11bobo3bo$o5b7obo11bob7o5bo$o4b2o3bobobo11bobobo3b2o4bo$bo3bo29bo3b
o$5bo29bo$3b3o29b3o$4b2o29b2o!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 16 THEME 6 GRID ]]
Here is the corresponding still-life that is converted to it:

Code: Select all

x = 31, y = 32, rule = B3/S23
8bo13bo$7bobo11bobo$8bo13bo$9b3ob2ob2ob3o$11bobo3bobo$14bobo$12b3ob3o
$11bo7bo$10bobo5bobo$11b2o5b2o$5b2o8bo8b2o$5bobo3b9o3bobo$6bobobo9bob
obo$2o6bob11obo6b2o$obo5bo13bo5bobo$bobo5b13o5bobo$2bobobo17bobobo$4b
ob19obo$4bo21bo$5b21o$2bo12bo12bo$2b6ob4o5b4ob6o$7bobo3bo3bo3bobo$bob
2o3bo3bo5bo3bo3b2obo$b2o2bo5bo7bo5bo2b2o$4bo6b2o5b2o6bo$b3o23b3o$bo27b
o$2b2o23b2o$3bo23bo$2bo25bo$2b2o23b2o!
[[ THUMBNAIL THUMBSIZE 2 VIEWONLY ZOOM 14 THEME 6 GRID ]]
This large still-life must be constructed from a much smaller still-life via a long series of components. Without these components, creating the large still-life (and hence creating the spaceship) would be impossible.

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » August 16th, 2021, 9:14 pm

MathAndCode wrote:
August 16th, 2021, 7:00 pm
While these seem like good topics for the news section, I don't think that they would be good topics for chapters in a book that is not specifically geared towards people with extensive prior knowledge of Conway's Game of Life. I think that for the book, it would best to break the complex projects up into chapters about their simpler parts.
Well, you probably have good instincts about that. However, the Life textbook already does a very thorough job of breaking things down into chapters (twelve of them) in pretty much exactly that way. It seems unlikely that we'll need to duplicate the effort of drilling down to simpler parts, since by the time this "Mathematical Artist" tribute book comes out, the textbook will be available too.

I was thinking more of relatively self-contained topics where maybe a little bit of a human-interest story could be told: for how many years this was an open problem, who worked on it when, who improved it or made a breakthrough or came up with the final solution, etc. Maybe it would work to explain some of these topics at a higher level without necessarily going through every tiny detail.

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Re: Thread for homepage article suggestions/contributions

Post by MathAndCode » August 16th, 2021, 9:23 pm

dvgrn wrote:
August 16th, 2021, 9:14 pm
Well, you probably have good instincts about that. However, the Life textbook already does a very thorough job of breaking things down into chapters (twelve of them) in pretty much exactly that way. It seems unlikely that we'll need to duplicate the effort of drilling down to simpler parts, since by the time this "Mathematical Artist" tribute book comes out, the textbook will be available too.
Yes, but I doubt that the majority of people who get that book will also get the textbook.
dvgrn wrote:
August 16th, 2021, 9:14 pm
I was thinking more of relatively self-contained topics where maybe a little bit of a human-interest story could be told: for how many years this was an open problem, who worked on it when, who improved it or made a breakthrough or came up with the final solution, etc.
This approach of chronicling the whole story seems like it would foster my suggestion of starting with the simple parts because in the early history of ConwayLife, the simple parts were the only things that were going on.

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » August 16th, 2021, 9:49 pm

MathAndCode wrote:
August 16th, 2021, 9:23 pm
Yes, but I doubt that the majority of people who get that book will also get the textbook.
I bet they will, though -- if they actually want to dig into that level of detail, which probably a lot of people won't...! The textbook will be available as a free PDF download, so it will be easy enough to link to it in any given chapter of this "Mathematical Artist" tribute book, and point to particular chapters whenever background is needed.

I'm going to want a printed copy of the textbook myself, but I'm not sure why exactly -- the PDF version is a lot more functional, since you can click on any illustration and get a pop-up RLE text file that can be copied into Golly. You definitely can't say that for the printed-on-a-dead-tree illustrations.

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Re: Thread for homepage article suggestions/contributions

Post by ColorfulGabrielsp138 » August 17th, 2021, 2:25 am

dvgrn wrote:
August 16th, 2021, 10:24 am

Three Possible Articles To Start With
* stable infinite line crosser and double-line (barge) crosser

* glider recipes for a series of increasingly larger "greyship" spaceships (see the first two entries in this list)

* self-synthesizing oblique loopship

These are mostly not my own projects; I didn't really do very much work on any of them, except maybe the stable line crosser (and even then I didn't contribute the recipes, which are the important part). It would make sense to me to do the article-writing collaboratively, if possible, similar to the spirit of the original projects -- and if this book project works out, basically get as many conwaylife.com community members into the chapter co-authors list as want to be there.
Maybe we can also put "Encyclopedia of numbers" into the "Articles".

Code: Select all

x = 21, y = 21, rule = LifeColorful
11.E$10.3E$10.E.2E$13.E4$2.2B$.2B$2B$.2B15.2D$19.2D$18.2D$17.2D4$7.C$
7.2C.C$8.3C$9.C!
I have reduced the glider cost of quadratic growth to eight and probably to seven. Looking for conduits...

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » August 17th, 2021, 9:14 am

ColorfulGabrielsp138 wrote:
August 17th, 2021, 2:25 am
Maybe we can also put "Encyclopedia of numbers" into the "Articles".
Is there some way for other people to know what this "Encyclopedia of numbers" is? It doesn't seem to be mentioned anywhere else on the forums. Why is it relevant?

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Re: Thread for homepage article suggestions/contributions

Post by ColorfulGabrielsp138 » August 17th, 2021, 9:22 am

dvgrn wrote:
August 17th, 2021, 9:14 am
ColorfulGabrielsp138 wrote:
August 17th, 2021, 2:25 am
Maybe we can also put "Encyclopedia of numbers" into the "Articles".
Is there some way for other people to know what this "Encyclopedia of numbers" is? It doesn't seem to be mentioned anywhere else on the forums. Why is it relevant?
It's a "collaborative popular article", as you have mentioned.

Code: Select all

x = 21, y = 21, rule = LifeColorful
11.E$10.3E$10.E.2E$13.E4$2.2B$.2B$2B$.2B15.2D$19.2D$18.2D$17.2D4$7.C$
7.2C.C$8.3C$9.C!
I have reduced the glider cost of quadratic growth to eight and probably to seven. Looking for conduits...

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » August 17th, 2021, 9:48 am

ColorfulGabrielsp138 wrote:
August 17th, 2021, 9:22 am
It's a "collaborative popular article", as you have mentioned.
That technically answers the question, and yet it doesn't really answer the question at all.

In what specific way does a collaborative popular article entitled "Encyclopedia of numbers" have anything to do with cellular automata?

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Re: Thread for homepage article suggestions/contributions

Post by GUYTU6J » August 17th, 2021, 9:58 am

dvgrn wrote:
August 17th, 2021, 9:48 am
In what specific way does a collaborative popular article entitled "Encyclopedia of numbers" have anything to do with cellular automata?
It refers to the article at User:ColorfulGalaxy/Encyclopedia of numbers, which lists a large amount of mildly interesting number-based random CA facts.
(EDIT: now that it got mentioned, why are the intervals divided like this? Is there anything special about 4, 32, 317, 3163, ...?)

Code: Select all

(-∞, 0) | [0, 4) | [4, 10) | [10, 32) | [32, 100) | [100, 317)
[317, 1000) | [1000, 3163) | [3163, 10000) | [10000, +∞)
(EDIT2: I see, it is related to sqrt(10)≈3.1623... but what is the benefit?)
Last edited by GUYTU6J on August 17th, 2021, 11:14 am, edited 2 times in total.
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Re: Thread for homepage article suggestions/contributions

Post by hotdogPi » August 17th, 2021, 9:59 am

It's this page: User:ColorfulGalaxy/Encyclopedia_of_numbers. Despite being in his userspace, I added most of the entries. I don't think it would be useful for this purpose, though.
User:HotdogPi/My discoveries

Periods discovered: 6,8,10-16,18,20,21G,22,24,25,27-31,32SG,35,36,40,42,45,48,50,54G,55G,57G,60,63-66,70,74S,75,76S,84,96S,100,117G,120,126,128S,138,147,156,196S,217,486,576

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Re: Thread for homepage article suggestions/contributions

Post by ColorfulGabrielsp138 » August 18th, 2021, 2:41 am

hotdogPi wrote:
GUYTU6J wrote:
It's based on this, this and this article. But the latter two didn't mention imaginary numbers, unfortunately.

Code: Select all

x = 21, y = 21, rule = LifeColorful
11.E$10.3E$10.E.2E$13.E4$2.2B$.2B$2B$.2B15.2D$19.2D$18.2D$17.2D4$7.C$
7.2C.C$8.3C$9.C!
I have reduced the glider cost of quadratic growth to eight and probably to seven. Looking for conduits...

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Re: Thread for homepage article suggestions/contributions

Post by dvgrn » September 18th, 2021, 12:30 pm

A follow-up email came in today from the Cellular Automata in India Research Group, about their upcoming book:
Please find this mail as a gentle reminder of the proposed article(s) in our book on Conway (The Mathematical Artist). Is there any progress on it? Like, have you decided the title(s) of your article(s)? Please let us know.

Thanks and best regards,

Kamalika
I'm going to try and write up a quick introductory article about line crossers in the LifeWiki Articles subspace (it's not its own namespace, just part of the main namespace, at least as things currently stand -- same as Tutorials.

I think MathAndCode's response above could easily be expanded into a complete LifeWiki article and/or book chapter, maybe about the glider-constructible greyships since it seems to be heading in that direction. It kind of stops in the middle at the moment, since it shows a still life that needs to be activated to make the greyship, but doesn't show how it's done.

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