1. Integration in \v{C}ech theories and a bound on entropy
- Author
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Hernández-Corbato, Luis, Nieves-Rivera, David Jesús, del Portal, Francisco Romero Ruiz, and Sánchez-Gabites, Jaime Jorge
- Subjects
Mathematics - Algebraic Topology ,Mathematics - Dynamical Systems - Abstract
The evaluation of Alexander-Spanier cochains over formal simplices in a topological space leads to a notion of integration of Alexander-Spanier cohomology classes over \v{C}ech homology classes. The integral defines an explicit and non-degenerate pairing between the Alexander-Spanier cohomology and the \v{C}ech homology. Instead of working on the limits that define both groups, most of the discussion is carried out "at scale $\mathcal U$", for an open covering $\mathcal U$. As an application, we generalize a result of Manning to arbitrary compact spaces $X$: we prove that the topological entropy of $f \colon X \to X$ is bounded from below by the logarithm of the spectral radius of the map induced in the first \v{C}ech cohomology group.
- Published
- 2021