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Question on Functional Powers

  1. Sep 8, 2011 #1
    I was reading on wikipedia about "functional powers", but I can't seem to find anything on it outside of this one section. I was wondering if there's any way to show anything for f^n(x). This is more of a general plea for more information on the topic than a specific question.

    Oh and here's the wikipdia page I mentioned.http://en.wikipedia.org/wiki/Function_composition#Functional_powers"
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Sep 8, 2011 #2
    Functional powers are used for example in Banach fixed point theorem http://en.wikipedia.org/wiki/Banach_fixed_point_theorem where one take a function f and investigates the limit of


    Also check the theory of Markov chains, dynamics systems and fractals (i.e. iterated function systems). This used functional powers.
    Last edited by a moderator: Apr 26, 2017
  4. Sep 8, 2011 #3
    Fixpoints are also very relevant in type theory and functional programming. The fixpoint function fix f = f(f(f(...))) allows for general recursion (which is useful for programmers), but opens the possibility of nonterminating programs (infinite loops) which correspond under the Curry-Howard isomorphism to proofs of false propositions.
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