Invariants of closed braids via counting surfaces

Michael Brandenbursky

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arXiv · 1209.1308

Invariants of closed braids via counting surfaces

Michael Brandenbursky

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Abstract

A Gauss diagram is a simple, combinatorial way to present a link. It is known that any Vassiliev invariant may be obtained from a Gauss diagram formula that involves counting subdiagrams of certain combinatorial types. In this paper we present simple formulas for an infinite family of invariants in terms of counting surfaces of a certain genus and number of boundary components in a Gauss diagram associated with a closed braid. We then identify the resulting invariants with partial derivatives of the HOMFLY-PT polynomial.

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Michael Brandenbursky. 2012-09-06. Invariants of closed braids via counting surfaces. https://arxiv.org/abs/1209.1308

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