Topological semigroups and fixed points
نویسندگان
چکیده
منابع مشابه
Common Fixed Points of Commutative Semigroups of Nonexpansive Mappings
Let C be a closed convex subset of a Banach space E. A mapping T on C is called a nonexpansive mapping if ‖Tx− Ty‖ ≤ ‖x− y‖ for all x, y ∈ C. We denote by F (T ) the set of fixed points of T . Kirk [21] proved that F (T ) is nonempty in the case that C is weakly compact and has normal structure. See also [3, 4, 5, 14] and others. If C is weakly compact and E has the Opial property, then C has n...
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A universal schema for diagonalization was popularized by N.S. Yanofsky (2003), based on a pioneering work of F.W. Lawvere (1969), in which the existence of a (diagonolized-out and contradictory) object implies the existence of a fixed-point for a certain function. It was shown that many self-referential paradoxes and diagonally proved theorems can fit in that schema. Here, we fi...
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ژورنال
عنوان ژورنال: Illinois Journal of Mathematics
سال: 1970
ISSN: 0019-2082
DOI: 10.1215/ijm/1256052955