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Fixed points of nonexpansive maps in reflexive Banach spaces
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Nonexpansive fixed points in reflexive Banach spaces. Resolves Kirk's reflexive-space fixed-point problem: every nonexpansive selfmap of a nonempty closed bounded convex subset of a real reflexive Banach space has a fixed point. The result uses the original norm, without assuming uniform convexity.

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released 2026-09-24  |  1 theorem · 8 lemmas · 13 proofs · 7,931 words  |  PLAY LEVEL 1 »  (pdf)
Every nonexpansive selfmap of a nonempty closed bounded convex subset of a real reflexive Banach space has a fixed point. This resolves the reflexive-space fixed point problem for the given norm.

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