Kauffman brackets, character varieties, and triangulations of surfaces

Francis Bonahon; Helen Wong

doi:10.1090/conm/560/11099

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arXiv · 1009.0084

Kauffman brackets, character varieties, and triangulations of surfaces

Francis Bonahon·Helen Wong

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Abstract

A Kauffman bracket on a surface is an invariant for framed links in the thickened surface, satisfying the Kauffman skein relation and multiplicative under superposition. This includes representations of the skein algebra of the surface. We show how an irreducible representation of the skein algebra usually specifies a point of the character variety of homomorphisms from the fundamental group of the surface to PSL_2(C), as well as certain weights associated to the punctures of the surface. Conversely, we sketch a proof of the fact that each point of the character variety, endowed with appropriate puncture weights, uniquely determines a Kauffman bracket. Details will appear elsewhere.

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BibTeX RIS

Francis Bonahon, Helen Wong. 2010-09-01. Kauffman brackets, character varieties, and triangulations of surfaces. https://doi.org/10.1090/conm%2F560%2F11099

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