A cohomology theory for colored tangles

Carmen Caprau

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arXiv · 1207.3373

A cohomology theory for colored tangles

Carmen Caprau

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Abstract

We employ the sl(2) foam cohomology to define a cohomology theory for oriented framed tangles whose components are labelled by irreducible representations of U_q(sl(2)). We show that the corresponding colored invariants of tangles can be assembled into invariants of bigger tangles. For the case of knots and links, the corresponding theory is a categorification of the colored Jones polynomial, and provides a tool for efficient computations of the resulting colored invariant of knots and links. Our theory is defined over the Gaussian integers Z[i] (and more generally over Z[i][a,h], where a,h are formal parameters), and enhances the existing categorifications of the colored Jones polynomial.

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Carmen Caprau. 2013-05-11. A cohomology theory for colored tangles. https://arxiv.org/abs/1207.3373

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