3 papers
math.AG2026
Tannakian duality and Gauss-Manin connections for a family of curves
Phùng Hô Hai, Võ Quôc Bao, Trân Phan Quôc Bao
Let be a smooth family of smooth projective varieties, where is a smooth affine curve over a field of characteristic We relate the differential fundamental group…
math.AG2025
Singular varieties and infinitesimal non-commutative Witt vectors
Phùng Hô Hai, João Pedro dos Santos, Äà o VÄn Thinh
Given a projective variety over an algebraically closed field , M. V. Nori introduced in 1976 a group scheme which accounts for principal bundles with finit…
math.AG2024
On the fundamental group schemes of certain quotient varieties
Indranil Biswas, Phùng Hô Hai, João Pedro dos Santos
In \cite{armstrong}, M. Armstrong proved a beautiful result describing fundamental groups of quotient spaces. In this paper we prove an analogue of Armstrong's theorem in the setti…