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arXiv · 1305.6042

Traceless SU(2) representations of 2-stranded tangles

Abstract

Given a 2-stranded tangle in a $\ZZ/2$ homology ball, $T\subset Y$, we investigate the character variety $R(Y,T)$ of conjugacy classes of traceless SU(2) representations of $π_1(Y\setminus T)$. In particular we completely determine the subspace of binary dihedral representations, and identify all of $R(Y,T)$ for many tangles naturally associated to knots in S^3. Moreover, we determine the image of the restriction map from $R(T,Y)$ to the traceless SU(2) character variety of the 4-punctured 2-sphere (the {\it pillowcase}). We give examples to show this image can be non-linear in general, and show it is linear for tangles associated to pretzel knots.

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BibTeXRIS

Yoshihiro Fukumoto, Paul Kirk, Juanita Pinzón-Caicedo. 2013-05-26. Traceless SU(2) representations of 2-stranded tangles. https://doi.org/10.1017/s0305004116000360

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