Below you can find more information about my Research (research interests, papers, and working groups), my Teaching page (courses and didactic materials), and my Notes, where I post general mathematical notes.

Research

My research is in the area of Dynamical Systems, focusing on piecewise smooth dynamics, entropy, and symbolic dynamics. On this page I list my published articles and preprints, my research projects, the research groups I participate in, and a list of collaborators and colleagues.

Projects

Non-deterministic Chaos in Piecewise Smooth Dynamical Systems
Study of the dynamics and entropy of Filippov vector fields via the orbit space — a quotient space on which the flow is deterministic and the classical tools of ergodic theory apply.
Entropy in Extended Symbolic Shifts
Generalization of Bernoulli shifts to non-invertible systems with two distinct alphabets, with explicit computation of the metric and folding entropies.

Recent work

  1. N. Martins, P. G. Mattos, R. Varão. Folding and Metric Entropies for Extended Shifts. Journal of Dynamics and Differential Equations, 2026.
  2. O. M. L. Gomide, P. G. Mattos, R. Varão. The Orbit Space Approach for Piecewise Smooth Vector Fields. Preprint, 2026.
  3. R. D. Euzébio, P. G. Mattos, R. Varão. Characterization of Non-deterministic Chaos in Two-dimensional Non-smooth Vector Fields. Differential Equations and Dynamical Systems, 2025.

Teaching

On this page I list the courses I have taught or am currently teaching, with didactic materials available on each course page.

Notes

Here I post general mathematical notes — expository, study, or reference — without any commitment to rigor or completeness.