Deformation theory of Cohen-Macaulay approximation
arXiv:1907.10405 · doi:10.1016/j.jalgebra.2020.09.039
Abstract
In a previous article (J. Algebra 367 (2012), 142-165) we established axiomatic parametrised Cohen-Macaulay approximation which in particular was applied to pairs consisting of a finite type flat family of Cohen-Macaulay rings and modules. In this sequel we study the induced maps of deformation functors and deduce properties like smoothness and injectivity under general, mainly cohomological conditions on the module.
v4, 23 pages. Definition 4.1 is changed. Some arguments have been expanded. A few minor additions. This preprint supersedes section 8, 9 and 11 in arXiv: 1103.2712. The article is published with open access. https://doi.org/10.1016/j.jalgebra.2020.09.039. arXiv admin note: text overlap with arXiv:1103.2712