Rodríguez Sanjurjo, José Manuel
(1990)
*Selections of multivalued maps and shape domination.*
Mathematical Proceedings of the Cambridge Philosophical Society, 107
(Part 3).
pp. 493-499.
ISSN 0305-0041

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Official URL: http://journals.cambridge.org/abstract_S0305004100068778

## Abstract

Given an approximate mapping f − ={f k }:X→Y between compacta from the Hilbert cube [K. Borsuk, Fund. Math. 62 (1968), 223–254, the author associates with f − a (u.s.c.) multivalued mapping F:X→Y . If F is single-valued, F and f − induce the same shape morphism, S(F)=S(f − ) . If Y is calm [Z. Čerin, Pacific J. Math. 79 (1978), no. 1, 69–91 and all F(x) , x∈X , are sufficiently small sets, then the existence of a selection for F implies that S(f − ) is generated by some mapping X→Y . If F is associated with f − and admits a coselection (a mapping g:Y→X such that y∈F(g(y)) , for y∈Y ), then S(f − ) is a shape domination and therefore sh(Y)≤sh(X) . If Y is even an FANR, then every sufficiently small multivalued mapping F:X→Y , which admits a coselection, induces a shape domination S(F) .

Item Type: | Article |
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Uncontrolled Keywords: | Shape theory, Set-valued maps, Selections |

Subjects: | Sciences > Mathematics > Geometry Sciences > Mathematics > Topology |

ID Code: | 17050 |

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Deposited On: | 07 Nov 2012 11:21 |

Last Modified: | 07 Feb 2014 09:40 |

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