
Wang Tiles and Turing Machines - gwern
https://grahamshawcross.com/2012/10/12/wang-tiles-and-turing-machines/
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diego898
These are a very interesting part of Greg Egan's Diaspora:
[https://en.wikipedia.org/wiki/Diaspora_(novel)](https://en.wikipedia.org/wiki/Diaspora_\(novel\))

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jamesrcole
FWIW the short story that that part of the book is based on is available for
under a dollar

Wang's Carpets, by Greg Egan
[https://www.amazon.com/gp/aw/d/B009ZVKQVS/](https://www.amazon.com/gp/aw/d/B009ZVKQVS/)

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panic
Here's another post which goes into more detail about the mapping from Turing
machines to sets of Wang tiles:
[https://moyix.wordpress.com/2012/04/06/computing-with-
tiles/](https://moyix.wordpress.com/2012/04/06/computing-with-tiles/)

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hinkley
Wang tiles remind me quite a bit of the Game of Life. From the article, tiles
were found to be Turing Complete in the '70s.

Wasn't Conway's Game proven to be Turing Complete much later? I find that a
little surprising if so.

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progval
Yes, with a right set of Wang tiles, once you set a row, there is only one
solution for each of the other row, and they can be built using local rules.
So it's really like a 1D cellular automaton if you put each time step of the
automaton on top of each other.

I can't find an early proof of Turing-completeness of Life. there is a paper
from 1974 has all the building blocks [1], but the authors got lazy: “From
here on, it is just a matter of engineering to construct an arbitrarily
powerful (albeit slow) computer. Our engineer has been given the tools - let
him finish the job”

[1]:
[https://dl.acm.org/citation.cfm?id=811303](https://dl.acm.org/citation.cfm?id=811303)

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ShannonAlther
Magic: the Gathering is also Turing complete.

[https://www.toothycat.net/~hologram/Turing/](https://www.toothycat.net/~hologram/Turing/)

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agumonkey
Got to see these used by Nicolas Schabanel, Damien Woodz and others for DNA
(the molecule) computing. Quite mind blowing.

