nLab Nielsen invariant

Idea

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References

The original article:

• Jakob Nielsen: Über die Minimalzahl der Fixpunkte bei den Abbildungstypen der Ringflächen, die Minimalzahl der Fixpunkte bei den Abbildungstypen der Ringflächen, Math. Ann. 82 1-2 (1920) 83-93 [doi:10.1007/BF01457977]

Nielsen invariants and Reidemeister torsion are rather related. There are many article now on this relation, cf.

• Alexander Fel’shtyn, New directions in Nielsen-Reidemeister theory, arxiv/0712.2601; Nielsen theory, Floer homology and a generalisation of the Poincare-Birkhoff theorem, arxiv/0807.0045; The growth rate of Floer homology and symplectic zeta function, arxiv/1101.4495

There are also some precursors like dilogarithm functions from the end of 19th century, closely related to the subject.