Fixed-point space: Difference between revisions

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imported>David Eppstein
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[[Category:Fixed points (mathematics)]]
[[Category:Fixed points (mathematics)]]

Latest revision as of 11:05, 26 December 2025

Template:Short description In mathematics, a Hausdorff space X is called a fixed-point space if it obeys a fixed-point theorem, according to which every continuous function f:XX has a fixed point, a point x for which f(x)=x.Template:R

For example, the closed unit interval is a fixed point space, as can be proved from the intermediate value theorem. The real line is not a fixed-point space, because the continuous function that adds one to its argument does not have a fixed point. Generalizing the unit interval, by the Brouwer fixed-point theorem, every compact bounded convex set in a Euclidean space is a fixed-point space.Template:R

The definition of a fixed-point space can also be extended from continuous functions of topological spaces to other classes of maps on other types of space.Template:R

References

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