Math Seminars.

Anna Bravo (U of M visitor),
Smoothness and arithmetical schemes


We study the notion of quasi-smoothness introduced by O. Villamayor in some recent works. This notion makes possible to associate a "canonical tangent bundle" to certain arithmetical schemes. In this context we can associate a "jacobian ideal" to any irreducible scheme embedded in a quasi-smooth scheme. We describe the class of centers so that quasi-smoothness is preserved by blowing-ups. Finally we characterize this class of centers in terms of the jacobian ideal.