{ "id": "1810.05813", "version": "v1", "published": "2018-10-13T07:49:09.000Z", "updated": "2018-10-13T07:49:09.000Z", "title": "The absolutely Koszul and Backelin-Roos properties for spaces of quadrics of small codimension", "authors": [ "Rasoul Ahangari Maleki", "Liana M. Şega" ], "comment": "37 pages", "categories": [ "math.AC" ], "abstract": "Let $\\kk$ be a field and let $R$ be a standard graded quadratic $\\kk$-algebra with $\\dim_{\\kk}R_2\\le 3$. We construct a graded surjective Golod homomorphism $\\varphi \\colon P\\to R$ such that $P$ is a complete intersection of codimension at most $3$. Furthermore, we show that $R$ is absolutely Koszul (that is, every finitely generated $R$-module has finite linearity defect) if and only if $R$ is Koszul if and only if $R$ is not a trivial fiber extension of a standard graded $\\kk$-algebra with Hilbert series $(1+2t-2t^3)(1-t)^{-1}$. In particular, we recover earlier results on the Koszul property of Backelin, Conca and D'Al\\`i.", "revisions": [ { "version": "v1", "updated": "2018-10-13T07:49:09.000Z" } ], "analyses": { "subjects": [ "13D02" ], "keywords": [ "absolutely koszul", "backelin-roos properties", "small codimension", "trivial fiber extension", "finite linearity defect" ], "note": { "typesetting": "TeX", "pages": 37, "language": "en", "license": "arXiv", "status": "editable" } } }