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arXiv · 1909.13502

Cauchy-Schwarz functions and convex partitions in the ray space of a supertropical quadratic form

Zur Izhakian·Manfred Knebusch
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Abstract

Rays are classes of an equivalence relation on a module V over a supertropical semiring. They provide a version of convex geometry, supported by a "supertropical trigonometry" and compatible with quasilinearity, in which the CS-ratio takes the role of the Cauchy-Schwarz inequality. CS-functions which emerge from the CS-ratio are a useful tool that helps to understand the variety of quasilinear stars in the ray space Ray(V). In particular, these functions induce a partition of Ray(V) into convex sets, and thereby a finer convex analysis which includes the notions of median, minima, glens, and polars.

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Zur Izhakian, Manfred Knebusch. 2019-09-30. Cauchy-Schwarz functions and convex partitions in the ray space of a supertropical quadratic form. https://arxiv.org/abs/1909.13502

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