Twisted Alexander polynomials on curves in character varieties of knot groups

Taehee Kim; Takahiro Kitayama; Takayuki Morifuji

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arXiv · 1301.1447

Twisted Alexander polynomials on curves in character varieties of knot groups

Taehee Kim·Takahiro Kitayama·Takayuki Morifuji

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Abstract

For a fibered knot in the 3-sphere the twisted Alexander polynomial associated to an SL(2,C)-character is known to be monic. It is conjectured that for a nonfibered knot there is a curve component of the SL(2,C)-character variety containing only finitely many characters whose twisted Alexander polynomials are monic, i.e. finiteness of such characters detects fiberedness of knots. In this paper we discuss the existence of a certain curve component which relates to the conjecture when knots have nonmonic Alexander polynomials. We also discuss the similar problem of detecting the knot genus.

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BibTeX RIS

Taehee Kim, Takahiro Kitayama, Takayuki Morifuji. 2013-02-10. Twisted Alexander polynomials on curves in character varieties of knot groups. https://arxiv.org/abs/1301.1447

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