In article ,
John Larkin wrote:
[....]
Of course you can't determine what a small change does to a real-life
chaotic system, because there's nothing to use as a no-stimulus
reference. But you can simulate a chaotic system, with and again
without some stimulus, and compare the results. In a healthy chaotic
system, any, even the tiniest, change results in increasing effects;
if you wait long enough, any small disturbance grows to total,
grand-scale differences in system state. The longterm differences
between a small pertubation and a large one are indistinguishable;
*everything* looks different.


When I lift my arm it appears to move smoothly upwards. The nerves and
muscles are in fact a chaotic system. If you look at one cell, for lift
to lift, the action of that cell can't be predicted. My arm, however,
still rises smoothly.

The "hit and miss" regulator's pattern of on and off is hugely different
when you make a small change in the load but the output voltage remains
near constant.

Both these are examples of systems that robustly chaotic and yet the
average results are easy to predict.

If you wash your car, you may indeed change where the thunderstorm
happens, however, you won't bring on a new ice age, or at least the oddds
are so low they aren't worth bothering with. If instead, you decreased
the output of the sun by 20%, a new ice age is going to happen.


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