A cellular automaton (CA) is defined by four attributes: |
1. The state space, the model of the world,
a collection of cells. |
2. The neighborhood (nbhd) of a cell. Those
cells whose current states affect the next state of a cell. |
3. The number of states a cell can assume.
This measures the level of detail at which we view the cells. |
4. The rule of the CA: how the current states of
the cells in the nbhd determine the next state of a cell. |
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This seems awfully simple, especially if the number of states
is few and the neighborhood size small. As a hint of the possible richness involved, we
calculate the number of CA rules. |
Cellular automata are used to model physical, chemical, biological, and
social interactions. |
For many of these applications, the exact positions of live cells in the
neighborhood is not as important as the number of live cells. |
Such CA are called totalistic. |
We are interested in an extension of this notion
called outer totalistic.
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