On the torsion of the differential module of a curve singularity
Let R be a complete analytic local k-algebra of dimension one without zero divisors over an algebraically closed field k of characteristic zero. This paper investigates the author's conjecture [cf. Math. Z. 81, 326-354 (1963; Zbl 0113.263)]: R is regular iff \(\Omega_{R/k}\) is torsion-free. In particular the author introduces a ring \(R^*\) between R and \(R_ 1\), the first quadratic transform, and shows that if \(\Omega_{R^*_ k}\) has torsion then R is not regular.
scientific article; zbMATH DE number 4144111