出典:Wikipedia
出典:『Wikipedia』 (2010/12/03 10:40 UTC 版)
A mathematical object X has the fixed point property if every suitably well-behaved mapping from X to itself has a fixed point. It is a special case of the fixed morphism property. The term is most commonly used to describe topological spaces on which every continuous mapping has a fixed point. But another use is in order theory, where a partially ordered set P is said to have the fixed point property if every increasing function on P has a fixed point.