In the next experiment,  each CA sums up its cells, and when both CA come up with equal cell sums, CA-2 is killed. The image portrays two CA evolving asynchronously, and since the above condition is not met, they live happily ever after. The graph depicts total ages of three CA. CA-1 is the stem process, and the other two are transient processes

CA-3 stop age is controlled by CA-2 mean age. Since CA-3 cell ages are below stop age the CA evolves as usual.   From time  30 – 45  CA-2 donates its age increment to CA-3, which brings  cell ages closer to stop age, and CA-3 pauses. Both CA still compare their cell sums. At t = 53 both cell sums are equal and at t=54 CA-2 dies.

Since CA-2 is dead stop age = 0, and CA-3 starts aging again. Note that during its pause it lost age, and now it regains it.

Both cell sums oscillate, then CA-3 pauses, at t=53 they meet, and at t=54 CA-2 dies.


The condition which specifies  the outcome  after the two cell sums become equal, indicates when this event happens. It is an indicator condition. Without the killing of CA-2 we would not have  been aware of this event. We might  prefer a more benign outcome, like planting a zygote, and creating a new process.

nca3 zygote -> effect[no,1000]; go[50]; go[60]; go[70] storeparams; restoreparams If[j >30 && j < 45, donate[3, 2]]; If[sa[[2]] == sa[[3]], killca[2];  move[3, nowdat[[2 , 7]]-10]; go[100];

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