Let k be a field and let I be a monomial ideal in the polynomial ring Q = k[x1, . . . , xn]. In her thesis, Taylor introduced a complex which provides a finite free resolution for Q/I as a Q-module. Later, Gemeda constructed a differential graded structure on the Taylor resolution. More recently, Avramov showed that this differential graded algebra admits divided powers. We generalize each of these results to monomial ideals in a skew polynomial ring R. Under the hypothesis that the skew commuting parameters defining R are roots of unity, we prove as an application that as I varies among all ideals generated by a fixed number of monomials of degree at least two in R, there is only a finite number of possibilities for the Poincaré series of k over R/I and for the isomorphism classes of the homotopy Lie algebra of R/I in cohomological degree larger or equal to two.
[1]
Gennady Lyubeznik,et al.
A new explicit finite free resolution of ideals generated by monomials in an R-sequence
,
1988
.
[2]
David A. Buchsbaum,et al.
Algebra Structures for Finite Free Resolutions, and Some Structure Theorems for Ideals of Codimension 3
,
1977
.
[3]
A. Kustin.
The Minimal Resolution of a Codimension Four Almost Complete Intersection Is a DG-Algebra
,
1994
.
[4]
E. F. Assmus.
On the homology of local rings
,
1959
.
[5]
Luigi Ferraro,et al.
Differential graded algebra over quotients of skew polynomial rings by normal elements
,
2019,
Transactions of the American Mathematical Society.
[6]
L. L. Avramov,et al.
OBSTRUCTIONS TO THE EXISTENCE OF MULTIPLICATIVE STRUCTURES ON MINIMAL FREE RESOLUTIONS
,
1981
.