===== Cellular Automata =====

Picture a grid of cells:

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Each cell is now given a set of rules: Each rule tells the cell to look at 4 of its nearest neighbors and count the number of white cells. If there are more than 3 white cells surrounding it, it should change its color to black. 

Imagine that for the grid above you now ask each cell to count the cells around it and remember which color it should become next; and when you give the signal "GO" all cells should change their color to the new (remembered) color. 

What will happen to the above grid when you yell GO?  (Cells at the edge will look at the cell on the oposit side of the grid.)


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Recently an RU student, Hrafn Þorri Þórisson, created [[http://cadia.ru.is/wiki/public:velaldin:main|a system for building cellular automata systems]]. He implemented a rule that Wolfram (Wolfram 2002) calls "Rule 30". This rule produced a pattern like this: 

{{:public:e-217-prog-2010-1:thorisson-simulation-2:rule30.png|Rule 30}}

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Interestingly, nature seems to implement this rule in some ways too: 

{{:public:e-217-prog-2010-1:thorisson-simulation-2:800px-textile_cone.jpg?700|Conc}}

EOF