Macaulay-like marked bases

Autor: Bertone, Cristina, Cioffi, Francesca, Roggero, Margherita
Rok vydání: 2012
Předmět:
Zdroj: Journal of Algebra and its Applications, Volume 16, Issue 5, 1 May 2017, Article number 1750100
Druh dokumentu: Working Paper
DOI: 10.1142/S0219498817501006
Popis: We define marked sets and bases over a quasi-stable ideal $\mathfrak j$ in a polynomial ring on a Noetherian $K$-algebra, with $K$ a field of any characteristic. The involved polynomials may be non-homogeneous, but their degree is bounded from above by the maximum among the degrees of the terms in the Pommaret basis of $\mathfrak j$ and a given integer $m$. Due to the combinatorial properties of quasi-stable ideals, these bases behave well with respect to homogenization, similarly to Macaulay bases. We prove that the family of marked bases over a given quasi-stable ideal has an affine scheme structure, is flat and, for large enough $m$, is an open subset of a Hilbert scheme. Our main results lead to algorithms that explicitly construct such a family. We compare our method with similar ones and give some complexity results.
Comment: 30 pages. Final version. In the present version Section 6 about flatness is improved, and new subsections concerning comparison with other existing computational methods (Section 7.1) and some complexity results (Section 7.2) were added
Databáze: arXiv