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arXiv · 0705.2441

An algorithm for lifting points in a tropical variety

Anders Nedergaard Jensen·Hannah Markwig·Thomas Markwig
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Abstract

The aim of this paper is to give a constructive proof of one of the basic theorems of tropical geometry: given a point on a tropical variety (defined using initial ideals), there exists a Puiseux-valued ``lift'' of this point in the algebraic variety. This theorem is so fundamental because it justifies why a tropical variety (defined combinatorially using initial ideals) carries information about algebraic varieties: it is the image of an algebraic variety over the Puiseux series under the valuation map. We have implemented the ``lifting algorithm'' using Singular and Gfan if the base field are the rational numbers. As a byproduct we get an algorithm to compute the Puiseux expansion of a space curve singularity in (K^{n+1},0).

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Anders Nedergaard Jensen, Hannah Markwig, Thomas Markwig. 2009-07-28. An algorithm for lifting points in a tropical variety. https://arxiv.org/abs/0705.2441

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