Skip to main content
  • Research Article
  • Open access
  • Published:

The Lefschetz-Hopf theorem and axioms for the Lefschetz number

Abstract

The reduced Lefschetz number, that is, where denotes the Lefschetz number, is proved to be the unique integer-valued function on self-maps of compact polyhedra which is constant on homotopy classes such that (1) for and ; (2) if is a map of a cofiber sequence into itself, then ; (3) , where is a self-map of a wedge of circles, is the inclusion of a circle into the th summand, and is the projection onto the th summand. If is a self-map of a polyhedron and is the fixed point index of on all of , then we show that satisfies the above axioms. This gives a new proof of the normalization theorem: if is a self-map of a polyhedron, then equals the Lefschetz number of . This result is equivalent to the Lefschetz-Hopf theorem: if is a self-map of a finite simplicial complex with a finite number of fixed points, each lying in a maximal simplex, then the Lefschetz number of is the sum of the indices of all the fixed points of .

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Martin Arkowitz.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Arkowitz, M., Brown, R.F. The Lefschetz-Hopf theorem and axioms for the Lefschetz number. Fixed Point Theory Appl 2004, 465090 (2004). https://doi.org/10.1155/S1687182004308120

Download citation

  • Received:

  • Published:

  • DOI: https://doi.org/10.1155/S1687182004308120