Initial ideals of generic ideals and variations of Moreno-Soc\'{i}as conjecture

Koichiro Tani

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arXiv · 2501.17383

Initial ideals of generic ideals and variations of Moreno-Soc\'{i}as conjecture

Koichiro Tani

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Abstract

It is known that the initial ideals of generic ideals are the same. Moreno-Soc\'{i}as conjectured that the initial ideal of generic ideals with respect to the degree reverse lexicographic order is weakly reverse lexicographic. In the first half of this paper, we study the initial ideal of generic ideals for arbitrary monomial order and prove that the initial ideal of generic ideals is Borel-fixed. It can be considered as a weakened version of Moreno-Soc\'{i}as conjecture. In the second half, we propose a new method of the computation of the initial ideal of generic ideals using stability condition of Gr\"{o}bner bases. We apply the method in the case of lexicographic order and study the relationship between the lexsegment ideal and the initial ideal of generic ideals. This study aims to bound the maximal degree of Gr\"{o}bner basis. At the last, we propose questions that can be considered as a lexicographic analogue of Moreno-Soc\'{i}as conjecture.

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Koichiro Tani. 2025-01-29. Initial ideals of generic ideals and variations of Moreno-Soc\'{i}as conjecture. https://arxiv.org/abs/2501.17383

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