2025/11/12 by Pérez, Pedro D. González
#Algebraic Geometry (math.AG) #FOS: Mathematics #Primary 14M25 #Secondary 32S25
paper · doi:10.48550/arxiv.2511.09126
Let (S, 0) ⊂ (ℂd+1,0) be an irreducible germ of hypersurface. The germ (S,0) is quasi-ordinary if (S,0) has a finite projection to (ℂd,0) which is unramified outside the coordinate hyperplanes. This implies that the normalization of S is a toric singularity. One has also a monomial variety associated to S, which is a toric singularity with the same normalization, and with possibly higher embedding dimension. Since (S,0) is quasi-ordinary, the extension of the Jacobian ideal of S to the local ring of its normalization is a monomial ideal. We describe this monomial ideal by comparing it with the \em logarithmic Jacobian ideals of S and of its associated monomial variety and we give some applications.