Beyond Wolfram's Classification
Posted: August 26th, 2020, 11:46 am
As it is well known, Stephen Wolfram defined four main categories of CA. His classification is not rigorous and relies on human intuition. However, most rules are easy to put into one of the 4 classes.
If we define a rule that allows coexistence of several "sub-behaviors", it may exhibit, depending in the pattern, the behavior of 2 or or more classes (the basic classification remains true though for a particular subset of patterns).
One example I already have demonstrated here.
Two more examples. B3/S0123 is an exploding rule with average density roughly twice higher than Seeds. If we transform into a 3-color 4-state cyclical rule, it still explodes ("islands" of each color independently). However, if we augment the 3-color version with the following additional rule, patterns tend to stabilize after a color collision and random soups usually stabilize rather quickly:
The additional rule: a new cell of a certain color is born, of surrounded by 2 cells of a different color and 1 cell of the third color, T3a12c21c-0n1n2n3n is m rule table generator's notation.
Note that the stabilization process, if started after a sufficient 1 color chaotic growth, produces a structure that resembles very realistic maps of lakes and marshes (compare the output of this pattern to the map of Northern Canada or Finland). Better to see it in Golly; A nice map emerges after 15000 generations.
If we transform the standard Conway's Game of Life into a 3-color cyclical rule, we get a chaotic behavior of approximately the same density as Seeds, if we add the following rule and make two colors collide:
A cell of color A is born, if surrounded by 1 cell of the color A and 2 cells of another color:
Now, this rule table actually contains a couple of other rules enacted when all 3 color collide, which produces a slowly growing homogeneous stable circular pattern (it's stable in itself, but grows due to the exploding 2-color collision on the edges):
1. A cell of color R is born, if surrounded by 1 R, 2 G and 2 B cells. Since the rule is defined cyclically, it implies that G is born, if surrounded by 1 G, 2 B and 2 R; B is born, if surrounded by 1 B, 2 R and 2 G.
2. A cell survives, if surrounded by 2 or 3 neighbors of any color (3-color extension of the original Life rule)
3. A cell survives, if surrounded by 4,5,6,7 or 8 neighbors, if all 3 colors are present among these neighbors.
There are many other types of behavior that I've encountered while playing with such rules. For example, some rules produce methuselahs of enormous longevity (10s of millions of generations) from random soups, because color collisions produce glider emitting "kernels" (not guns. kind of chaotic things) that constantly revitalize the pattern.
If we define a rule that allows coexistence of several "sub-behaviors", it may exhibit, depending in the pattern, the behavior of 2 or or more classes (the basic classification remains true though for a particular subset of patterns).
One example I already have demonstrated here.
Two more examples. B3/S0123 is an exploding rule with average density roughly twice higher than Seeds. If we transform into a 3-color 4-state cyclical rule, it still explodes ("islands" of each color independently). However, if we augment the 3-color version with the following additional rule, patterns tend to stabilize after a color collision and random soups usually stabilize rather quickly:
The additional rule: a new cell of a certain color is born, of surrounded by 2 cells of a different color and 1 cell of the third color, T3a12c21c-0n1n2n3n is m rule table generator's notation.
Code: Select all
x = 344, y = 101, rule = Triple_Swamps
7$11.3C$13.C$11.C.C$12.2C80$328.B!If we transform the standard Conway's Game of Life into a 3-color cyclical rule, we get a chaotic behavior of approximately the same density as Seeds, if we add the following rule and make two colors collide:
A cell of color A is born, if surrounded by 1 cell of the color A and 2 cells of another color:
Code: Select all
x = 18, y = 7, rule = Triple_Behavior_Life
2$2.A12.B$3.2A9.B$2.2A10.3B!1. A cell of color R is born, if surrounded by 1 R, 2 G and 2 B cells. Since the rule is defined cyclically, it implies that G is born, if surrounded by 1 G, 2 B and 2 R; B is born, if surrounded by 1 B, 2 R and 2 G.
2. A cell survives, if surrounded by 2 or 3 neighbors of any color (3-color extension of the original Life rule)
3. A cell survives, if surrounded by 4,5,6,7 or 8 neighbors, if all 3 colors are present among these neighbors.
Code: Select all
x = 21, y = 22, rule = Triple_Behavior_Life
2$6.A$7.A9.B.B$5.3A9.2B$18.B11$2.3C$4.C$3.C!