How CA evades a barrier

We continue exploring the wisdom of a two tailed reference CA depicted at the upper left corner. At t = 38 a barrier is placed at  location x = 38 (Compare with previous barrier experiments: Chapters 2, 3, and 31). The barrier  remains at location x =38  until t = 48, and is removed at  t = 49.  At  location x = 50, we plant a zygote ( t = 0 ). As CA grows it becomes wider and approaches the barrier. At t = 35 it pauses.  In order to evade the barrier, it starts recollecting its previous experience.  Without recall (= 0) it touches the barrier and its  left tail is short.  At recall = -5 it interacts heavily with the barrier. At recall = -8 it barely touches the barrier but the tail remains short. Finally recall = -10 evades the barrier.  The CA  strategy is to elongate its narrow body and grow its tail somewhat later than the reference CA.

The first graph below, depicts CA efforts to find a solution. It depicts the deviation of center of mass of the CA from that of the reference CA in the upper left corner . When the deviation is zero it is symmetric and  similar to the reference CA. The production graph depicts the price that CA paid for evading the barrier. Its production declined. All recalls beyond -9  evaded the barrier, yet the longer the body, the less cells were produced. Solution based on recall = -10 was therefore the best.

The upper graph depicts a CA repertory for evading an obstacle. (compare with chapters 34, 38). By planting 35 zygotes, it may be evaluated in parallell. In each CA a different state is recollected (activated).

barriertime = 38; barrierendtime = 48; statetime= 35; prevstate = *; agetime = 35; prevage = *;  preva[[1,*]] = a[[1,*]];  prevage[[1,*]] = age[[1,*]]; effect[1, 1, 25];

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