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arXiv · 2206.13171

On normal Seshadri stratifications

Rocco Chirivì·Xin Fang·Peter Littelmann
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Abstract

The existence of a Seshadri stratification on an embedded projective variety provides a flat degeneration of the variety to a union of projective toric varieties, called a semi-toric variety. Such a stratification is said to be normal when each irreducible component of the semi-toric variety is a normal toric variety. In this case, we show that a Gr\"obner basis of the defining ideal of the semi-toric variety can be lifted to define the embedded projective variety. Applications to Koszul and Gorenstein properties are discussed. Relations between LS-algebras and certain Seshadri stratifications are studied.

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Rocco Chirivì, Xin Fang, Peter Littelmann. 2022-06-27. On normal Seshadri stratifications. https://arxiv.org/abs/2206.13171

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