Normalization of Twisted Alexander Invariants
نویسندگان
چکیده
Twisted Alexander invariants of knots are well-defined up to multiplication of units. We get rid of this multiplicative ambiguity via a combinatorial method and define normalized twisted Alexander invariants. We can show that the invariants coincide with signdetermined Reidemeister torsion in a normalized setting and refine the duality theorem. As an application, we obtain stronger necessary conditions for a knot to be fibered than those previously known. Finally, we study a behavior of the highest degree of the normalized invariant.
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