Linear Maps in Minimal Free Resolutions of Stanley-Reisner Rings

In this short note we give an elementary description of the linear part of the minimal free resolution of a Stanley-Reisner ring of a simplicial complex <inline-formula> <math display="inline"> <semantics> <mo>&#916;</mo> </semantics> </math> &...

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Bibliographic Details
Main Author: Lukas Katthän
Format: Article
Language:English
Published: MDPI AG 2019-07-01
Series:Mathematics
Subjects:
Online Access:https://www.mdpi.com/2227-7390/7/7/605
Description
Summary:In this short note we give an elementary description of the linear part of the minimal free resolution of a Stanley-Reisner ring of a simplicial complex <inline-formula> <math display="inline"> <semantics> <mo>&#916;</mo> </semantics> </math> </inline-formula>. Indeed, the differentials in the linear part are simply a compilation of restriction maps in the simplicial cohomology of induced subcomplexes of <inline-formula> <math display="inline"> <semantics> <mo>&#916;</mo> </semantics> </math> </inline-formula>. Along the way, we also show that if a monomial ideal has at least one generator of degree 2, then the linear strand of its minimal free resolution can be written using only <inline-formula> <math display="inline"> <semantics> <mrow> <mo>&#177;</mo> <mn>1</mn> </mrow> </semantics> </math> </inline-formula> coefficients.
ISSN:2227-7390