
Cellular Automata: Rule 30 fed as input to Conway’s Game of Life (2019) [video] - torotonnato
https://www.youtube.com/watch?v=IK7nBOLYzdE
======
DonHopkins
I love the colorful persistent phosphor effect.

It reminds me of running Life and Munching Squares on a PDP-7 340 Vector
Graphics Display, with its beautiful P7 phosphor:

[https://www.youtube.com/watch?v=hB78NXH77s4](https://www.youtube.com/watch?v=hB78NXH77s4)

Conway's Game of LIFE in a DEC PDP-7 w/ Type 340 Display

Here is an implementation of John Conway's Game of Life on an 18 bit DEC PDP-7
with a DEC Type 340 X/Y point display. Patterns are stored on and can be
called from our new JK09 PDP-7 storage device which is what we use for UNIX
V0. We have set a few starter patterns including Bill Gosper's Glider Gun.

The sounds you hear are from the Type 347 display controller. They were
received using a Yaesu FT1XD radio in AM mode.

The world supports 1296 points (36 x 36). We are attempting to increase this
to 72 x 72 or 5184 points.

[https://www.youtube.com/watch?v=V4oRHv-
Svwc](https://www.youtube.com/watch?v=V4oRHv-Svwc)

DEC PDP-7 w/ Type 340 display running Munching Squares and Spirograph

Two display hacks run on PDP-7 serial number 129 with the Type 340 XY display
option. The 340 has a P7 phosphor has a slow decay which gives Munching
Squares an eerie afterglow. Both programs read the left switches to modify
patterns. A small AM radio was used to pick up RFI from the Type 347
controller. For the MIT AI lab hackers the Munching Squares "music" was
referred to as Munching Tunes.

~~~
tartoran
Yes, that has some mystical effect on me. I think I saw it when you shares it
the other day. How does the AM capture the sound? What exactly generates the
sound waves?

~~~
DonHopkins
It's electromagnetic interference from the electronics. A hulking powerful
"big iron" PDP-7 makes a much better RFI broadcast antenna than an iPhone, but
it broadcasts at much lower frequencies, that an AM radio can pick up.

You can hear a little bit of interference on an FM radio, but it sounds much
stronger and more interesting on the AM dial.

PDP-7's were actually relatively sleek fast inexpensive computers for the
time, and were only 18 bits compared to the PDP-6's and PDP-10's 36 bits. ("If
you're not working with 36 bits, you're not working with a full DEC!" -DIGEX)
But physically they still have a lot of "big iron" parts and use lots of power
like mainframes.

[https://en.wikipedia.org/wiki/Mainframe_computer](https://en.wikipedia.org/wiki/Mainframe_computer)

[https://en.wikipedia.org/wiki/PDP-7](https://en.wikipedia.org/wiki/PDP-7)

The other sibling post by nitrogen referred to "tempest", which is a (no
longer) secret NSA codename for "Telecommunications Electronics Materials
Protected from Emanating Spurious Transmissions", a certification for
shielding equipment from spying on it via electromagnetic radiation.

[https://en.wikipedia.org/wiki/Tempest_(codename)](https://en.wikipedia.org/wiki/Tempest_\(codename\))

The slower the computer, the more "details" you can hear of the computation.
Modern computers are so fast and have so much going on and are so much better
shielded (they need to be, since they have their own radios they don't want
their own RFI to interfere with), that they aren't nearly as interesting to
listen to on AM radio. I loved to listen to my Apple ][ on AM radio,
especially compiling my FORTH system and applications (it's satisfying to
listen to your own code you wrote compiling and running)!

~~~
tartoran
Thank you, this is a very interesting topic to me. I remember ,when I was a
kid in the 90s and had the Sound Blaster card, 1.0 or something quite cheap
and in certain situations I would hear very similar but quiet interference on
the headphones when there was no sound playing.

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brtkdotse
Neat! In a similar vein, here's Game of Life implemented in Game of Life:

[https://www.youtube.com/watch?v=xP5-iIeKXE8](https://www.youtube.com/watch?v=xP5-iIeKXE8)

~~~
andyjohnson0
According to Wikipedia, a cellular automaton running the game of life rules is
Turing complete. So it can compute anything that a Universal Turing Machine
can compute [1] - In other words, anything that a conventional computer can
compute.

[1]
[https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life](https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life)

~~~
wizzwizz4
Including Tetris.
[https://codegolf.stackexchange.com/q/11880/43394](https://codegolf.stackexchange.com/q/11880/43394)

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ajnin
Same account posted a similar video for rule 110 :
[https://www.youtube.com/watch?v=P2uhhAXd7PI](https://www.youtube.com/watch?v=P2uhhAXd7PI)

Pretty interesting !

~~~
brtkdotse
Fun fact is that rule 110 is Turing complete, which for me is mind blowing

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mkl
The Wikipedia article on Rule 30 is interesting:
[https://en.wikipedia.org/wiki/Rule_30](https://en.wikipedia.org/wiki/Rule_30)

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tomlockwood
I've been playing around with Cellular Automata recently too!!! Wish my viz
looked as good as this one, though :D

[https://lockwood.dev/automata/2020/03/28/bruteforcing-
beauti...](https://lockwood.dev/automata/2020/03/28/bruteforcing-beautiful-
cellular-automata-rulesets-with-golang.html)

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rasalas
Watching this video caused some noticeable motion aftereffects for me.

~~~
enchiridion
Can you elaborate?

~~~
urxvtcd
The bottom part "goes down" when you stop the video.

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hanoz
Slightly unnerving to see it fall victim to a kind of Kessler Syndrome,
preventing gliders from escaping eventually.

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jpalomaki
I have been watching some videos about quantum field theory[1]. Now that I saw
this, just got the random idea if there could be some relation between those
and cellular automaton.

Particles would be the "cells". Them being live or dead would be result of the
interactions of the underlying fields.

[1]
[https://en.wikipedia.org/wiki/Quantum_field_theory](https://en.wikipedia.org/wiki/Quantum_field_theory)

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pieterk
Would it be possible to advance the POV up as the game goes on?

Should be cool to see other planets etc etc.

~~~
xwdv
There are no other planets. They are entirely alone in their universe, and
will simply fly out to eternity in a futile search for other life.

~~~
leeno
There's one glider that comes back:
[https://youtu.be/IK7nBOLYzdE?t=112](https://youtu.be/IK7nBOLYzdE?t=112)

~~~
xwdv
Those didn’t come back from deep space they simply made a U-turn in low orbit
and returned to the surface.

In theory two gliders taking off at the same time at the right distance on a
long enough axis could collide in deep space and create something new, which
would then return to the planet surface like some kind of invasion, but I
doubt it.

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zuminator
The top half reminds me a bit of the old arcade game "Missile Command."

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DonHopkins
This is a beautiful combination, and reminiscent of Rudy Rucker's hybrid
cellular automata rule "EcoLiBra", that combined Life and Brian's Brain by
switching between them on a per-pixel basis, based on another cellular
automata rule, Anneal, running in a parallel plane.

Anneal decides whether each cell is land or water, and clumps cells into
oceans and continents that look like cow spots, with smoothly eroded
shorelines and long beaches. Life runs on land, and brain runs in water, and
they interact and stimulate each other along the beaches where land and water
meet.

Actually EcoLiBra uses "AntiLife" (aka "Death") on land, the ones-complement
of life, because that makes the empty space "1" for AntiLife stimulate Brain,
and the empty space "0" for brain stimulate Life, so the beach is a fertile
breeding ground that never dies out, and there's much more cross-species
stimulation and humping and birthing along the shores, then the children
disperse by swimming down into the deep ocean, or climbing up into the inland
hills.

[http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#EcoL...](http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#EcoLiBra)

>ECOLIBRA

>The JC EcoLiBra rule, a cross between Life and Brain.

>This rule is a cross between Life and Brain. The basic idea is that the cells
are divided between dark "sea" cells and light "land" cells. We run Brain in
the sea, and on land we run not Life but AntiLife. All the land cells are
normally firing cells, and the presence of an active AntiLife cell is signaled
by having a land cell which is not firing. Full details on EcoLiBra are in §

>The name EcoLiBra suggests 1) an ecology of Life and Brain, 2) a balanced
situation (equilibrium), and 3) the human intestinal bacteria Escherichia
coli, known as E. coli for short. The third connection is perhaps a bit
unsavory, but remember that E. coli cells are in fact the favorite "guinea
pigs" for present day genesplicing experiments. As one of the goals of CelLab
is to promote the development of artificial life, the designer gene connection
is entirely appropriate. I've given EcoLiBra a nice, symmetric start pattern,
but it also does fine if you press R to randomize the screen. You can make a
randomized screen a little more interesting by using the screen editor to
drill a big black hole in the center. This can be done by using the following
keystrokes

Here is an earlier somewhat simpler cellular automata rule that Rudy Rucker
made when he first started playing with the CAM-6 in 1987.

[http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#Brai...](http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#BraiLife)

>BRAILIFE

>The JC BraiLife rule after 213 generations. A hauler is about to hit a
butterfly just above and to the right of the center of the diamond shape.

>When I first started hacking cellular automata on the CAM-6 in 1987, I
couldn't quite see how to think of a completely new rule. So I decided a good
way to start might be to try combining some of the old rules, particularly the
rules Life and Brain.

>Life is very interesting, but it tends to die out. Brain, on the other hand,
is extremely hard to kill off; if anything, Brain is too persistent. So I
thought I might try running Life and Brain in parallel, using Brain to
stimulate Life, and using Life to dampen Brain.

>At first I had every firing Brain cell turn on a Life cell, and had every
firing Life cell turn off a Brain cell, but, run fullscreen, this reaction
quickly wipes Brain out. You can see the fullscreen reaction by loading
BraiLife, clearing all the screens, setting plane 4 to 1, and randomizing
plane 2. The keystrokes are as follows. Note that you do not press Enter after
answering the "Initialize planes" prompts called up by pressing I:

Rudy referrs to Anneal as "Vote" (with a twist of chaos is a tie-breaker):

[http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#Vote](http://www.rudyrucker.com/oldhomepage/celdoc/rules.html#Vote)

>VOTE

>The JC Vote rule, a few generations after a random start. Vote is a one-bit
rule where each cell calculates the NineSum of itself and its eight neighbors,
and then determines its new state on the basis of the NineSum. We can regard
this as EveryCell conducting a little election between 0 and 1 among the nine
cells in its neighborhood. If either 0 or 1 wins by a clear majority of 6
votes or more out of the nine votes, then that is the state which EveryCell
will take on. But if either 0 or 1 wins by a scant, sneaky majority of 5 votes
out of the nine, then the election is overturned, and EveryCell takes on the
color of the "losing" state. Vote is discussed in more detail in the Theory
chapter.

>The version of Vote shown here uses bit #1 as an "echo" of bit #0. This means
that cells will take on different colors if they have changed state in the
last generation. You can keep rerandomizing Vote by pressing R. It's a bit
startling to see what organic-looking shapes can arise from such a simple rule
acting on a rectangular grid.

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amelius
How much computational resources does this take? Is it ever growing, or can
you cut it off outside a certain window without it affecting the visible part?

~~~
wizzwizz4
I can answer the second bit: no. However, cutting it off at a certain point
won't affect anything, so long as you keep shrinking the cut off bit by one
each turn. Eventually you'll have nothing generating any more, but everything
you do generate will be accurate.

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soheil
Pretty random. I wonder if there is a way of thinking about this perceived
complexity with a higher dimension similar to the way imaginary numbers are
used.

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tartoran
Amazing. Looks like a warzone.

