5 papers
Regularity of infinitesimal automorphisms of involutive structures
Bernhard Lamel, Nicholas Braun Rodrigues
In this paper, we prove that infinitesimal automorphisms of an involutive structure are smooth. For this, we build a regularity theory for sections of vector bundles over an involu…
On a class of globally analytic Hypoelliptic operators with non-negative characteristic form
Nicholas Braun Rodrigues, Gregorio Chinni
The global analytic hypoellipticity is proved for a class of second order partial differential equations with non-negative characteristic form globally defined on the torus. The cl…
Smooth and Gevrey Microlocal Hypoellipticity for a Class of Hypocomplex Tube Structures
Nicholas Braun Rodrigues
We prove a smooth and Gevrey- microlocal hypoellipticity result for a system of complex vector fields associated with a real-analytic locally integrable structure of tube type,…
An FBI characterization for Gevrey vectors on hypo-analytic structures and propagation of Gevrey singularities
Nicholas Braun Rodrigues
In this work we prove an FBI characterization for Gevrey vectors on hypo-analytic structures, and we analyze the main differences of Gevrey regularity and hypo-analyticity concerni…
Approximate solutions of vector fields and an application to Denjoy-Carleman regularity of solutions of a nonlinear PDE
Nicholas Braun Rodrigues, Antonio V. da Silva
In this paper we study microlocal regularity of a solution of the equation \begin{equation*} u_t = f(x,t,u,u_x), \end{equation*} where is ultrad…