Fixed point theory for admissible pairs and maps in Frechet spaces via degree theory


New fixed point results are presented for admissible pairs and maps (admissible in the sense of Gorniewicz) defined on subsets of a Frechet space E. The proof relies on the notion of a pseudo open set, degree theory, and on viewing E as the projective limit of a sequence of Banach spaces.


Ruyun MA
Department of Mathematics, Northwest Normal University Lanzhou 730070, China

Donal  O’Regan
Department of Mathematics, National University of Ireland Galway, Ireland

Radu Precup
Department of Mathematics, Babes-Bolyai University, Cluj-Napoca, Romania


fixed point; admissible pair; degree theory

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R. Ma, D. O’Regan, R. Precup, Fixed point theory for admissible pairs and maps in Frechet spaces via degree theory, Fixed Point Theory 8 (2007) no. 2, 273-283.


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Fixed Point Theory

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