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arXiv · 1003.1101

Supertropical semirings and supervaluations

Zur Izhakian·Manfred Knebusch·Louis Rowen
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Abstract

We interpret a valuation $v$ on a ring $R$ as a map $v: R \to M$ into a so called bipotent semiring $M$ (the usual max-plus setting), and then define a \textbf{supervaluation} $ϕ$ as a suitable map into a supertropical semiring $U$ with ghost ideal $M$ (cf. [IR1], [IR2]) covering $v$ via the ghost map $U \to M$. The set $\Cov(v)$ of all supervaluations covering $v$ has a natural ordering which makes it a complete lattice. In the case that $R$ is a field, hence for $v$ a Krull valuation, we give a complete explicit description of $\Cov(v)$. The theory of supertropical semirings and supervaluations aims for an algebra fitting the needs of tropical geometry better than the usual max-plus setting. We illustrate this by giving a supertropical version of Kapranov's lemma.

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Zur Izhakian, Manfred Knebusch, Louis Rowen. 2010-10-12. Supertropical semirings and supervaluations. https://arxiv.org/abs/1003.1101

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