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arXiv · 2211.15394

Closures of T-homogeneous braids are real algebraic

Abstract

A link in $S^3$ is called real algebraic if it is the link of an isolated singularity of a polynomial map from $\mathbb{R}^4$ to $\mathbb{R}^2$. It is known that every real algebraic link is fibered and it is conjectured that the converse is also true. We prove this conjecture for a large family of fibered links, which includes closures of T-homogeneous (and therefore also homogeneous) braids and braids that can be written as a product of the dual Garside element and a positive word in the Birman-Ko-Lee presentation. The proof offers a construction of the corresponding real polynomial maps, which can be written as semiholomorphic functions. We obtain information about their polynomial degrees.

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Benjamin Bode. 2022-11-28. Closures of T-homogeneous braids are real algebraic. https://doi.org/10.2140/agt.2025.25.1075

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