ON COMMUTING FUNCTIONS,

Abstract

There is a rather well-known conjecture that if f and g are continuous functions from (0,1) to (0, 1) which commute (i.e., f(g(x)) = g(f(x))), then f and g have a common fixed point. The conjecture is known to be true in some special cases; for example, when f and g are polynomials. H. Cohen has proved the conjecture for the case when f and g have a property he calls fullness. In this memorandum the author generalizes Cohen's theorem to the case when f is full and g is arbitrary. This result is especially interesting because the author assumes a special form for only one of the functions. The methods used seem to be new, and the author feels that further work in this direction may eventually yield a proof of the conjecture in the case when one of the functions is of bounded variation. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1964
Accession Number
AD0608060

Entities

People

  • Jon H. Folkman

Organizations

  • RAND Corporation

Tags

DTIC Thesaurus Topics

  • Polynomials

Fields of Study

  • Mathematics

Readers

  • Mathematical Modeling and Probability Theory.
  • Military History of the United States in the 20th Century.