ArticleOriginal scientific text
Title
Generalized Lefschetz numbers of pushout maps defined on non-connected spaces
Authors 1
Affiliations
- Dipartimento di Matematica, Università di Milano, Via Saldini 50, 20133 Milano, Italy
Abstract
Let A, and be topological spaces and let , be continuous maps. For all self-maps , and such that and there exists a pushout map f defined on the pushout space . In [F] we proved a formula relating the generalized Lefschetz numbers of f, , and . We had to assume all the spaces involved were connected because in the original definition of the generalized Lefschetz number given by Husseini in [H] the space was assumed to be connected. So, to extend the result of [F] to the not necessarily connected case, a definition of generalized Lefschetz number for a map defined on a not necessarily connected space is given; it reduces to the original one when the space is connected and it is still a trace-like quantity. It allows us to prove the pushout formula in this more general case and therefore to get a tool for computing Nielsen and generalized Lefschetz numbers in a wide class of spaces.
Bibliography
- [B] R. F. Brown, The Lefschetz Fixed Point Theorem, Scott Foresman and Company, Chicago, 1971.
- [FH] E. Fadell and S. Husseini, The Nielsen Number on Surfaces, Contemp. Math. 21, AMS, Providence, 1983.
- [F] D. Ferrario, Generalized Lefschetz numbers of pushout maps, Topology Appl. 68 (1996) 67-81.
- [H] S. Y. Husseini, Generalized Lefschetz Numbers, Trans. Amer. Math. Soc. 272 (1982), 247-274.
- [J] B. J. Jiang, Lectures on Nielsen fixed point theory, Contemp. Math. 14, Amer. Math. Soc., Providence, 1983.
- [J1] B. J. Jiang, Periodic orbits on surfaces via Nielsen fixed point theory, in: Topology Hawaii (Honolulu, HI, 1990), 101-118.
- [P] R. A. Piccinini, Lectures on Homotopy Theory, North-Holland, Amsterdam, 1992.
- [S] J. Stallings, Centerless groups - an algebraic formulation of Gottlieb's theorem, Topology 4 (1965), 129-134.