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Re:Leslie Lamport revolutionized computer science with math ... by raegis on Tuesday May 24, 2022 @11:07PM (#31500155)
> I still wonder sometimes whether an infinite composition of continuous functions has to be continuous (limit of a sequence) ...

No, as you expected. Take f(x) = x^2 on [0,1]. Then f(f(f(...f(x))) converges to g(x) = { 0, if 0 <= x < 1; 1, if x=1 }

Re:Leslie Lamport revolutionized computer science with math ... by EGreg on Tuesday May 24, 2022 @11:42PM (#31500372)
Right. So now the question is -- are you able to give a physical example of physical (continuous) processes which can create a discontinuous output from a continuous initial state, in a finite amount of time? I think this is a sort of Zeno's paradox...
Re:Leslie Lamport revolutionized computer science with math ... by juhanima on Wednesday May 25, 2022 @06:38AM (#31502607)
Tossing a coin?
Re:Leslie Lamport revolutionized computer science with math ... by EGreg on Wednesday May 25, 2022 @07:33AM (#31503048)
No. The coin could land on its side, for instance, and stay there.

Consider a pencil that is placed almost vertically, and then later drops to a horizontal position. There is a period where it is "unsure" where to go, and the more perfectly balanced it starts out, the longer this period is (assuming no wind etc.)

That's what is being discussed.