English

A Combinatorial Study of the Fixed Point Index

Algebraic Topology 2025-06-02 v1

Abstract

We introduce a theory of integration with respect to the fixed point index, offering a substantial improvement over previous approaches based on the Lefschetz number. This framework eliminates several restrictive assumptions -- such as the need for definability, openness, or f-invariance of subspaces -- thereby allowing broader applicability. We also present a natural combinatorial adaptation of the fixed point index that extends the combinatorial Lefschetz number. This extension yields new topological and homotopical invariance results and facilitates the integration of real-valued functions with respect to fixed points.

Keywords

Cite

@article{arxiv.2505.24530,
  title  = {A Combinatorial Study of the Fixed Point Index},
  author = {Jesús A. Álvarez López and Alejandro O. Majadas-Moure and David Mosquera-Lois},
  journal= {arXiv preprint arXiv:2505.24530},
  year   = {2025}
}
R2 v1 2026-07-01T02:50:31.109Z