activity
20222026
collaborators

14 papers

math.AP2026

Qualitative-to-quantitative regularity for degenerate equations

Aelson Sobral, Eduardo V. Teixeira, José Miguel Urbano

We establish a principle that converts qualitative regularity into uniform interior estimates for degenerate equations. For the -Laplace equation, , we prove that local $C^…

math.AP2026

From qualitative smoothness to uniform estimates for fully nonlinear elliptic equations

Aelson Sobral, Eduardo V. Teixeira

We establish a general mechanism that turns qualitative smoothness into uniform, quantitative regularity estimates for fully nonlinear elliptic equations. The central conclusion is…

math.AP2026

Endpoint Differentiability Moduli for Fully Nonlinear Elliptic Equations

Aelson Sobral, Eduardo V. Teixeira

A classical consequence of Caffarelli's fully nonlinear regularity theory [L. A. Caffarelli, Ann. of Math. (2) 130 (1989), no. 1, 189-213] is that viscosity solutions of uniformly…

math.AP2026

The Monge--Ampère equation on graphs

Ahmed Alkhozaae, Julio D. Rossi, Aelson Sobral +1

We introduce a version of the Monge--Ampère equation on finite graphs, motivated by nonlinear graph-based interpolation and semi-supervised learning. The operator is defined as the…

math.AP2026

Uniform Lipschitz regularity for two-phase singularly perturbed fully nonlinear elliptic equations

Thialita M. Nascimento, Aelson Sobral, Eduardo V. Teixeira

We study sign-changing viscosity solutions of the singularly perturbed fully nonlinear equation $$ F(D^2u_\varepsilon) = \fracα{\varepsilon} β\left(\frac{u_\varepsilon}{\varepsilon…

math.AP2026

Lipschitz regularity for the parabolic obstacle problem

David Jesus, Aelson Sobral, José Miguel Urbano

We study the obstacle problem for the parabolic fractional Laplace equation \[\partial_t u+(-Δ_p)^su = 0\] in the degenerate range . We prove that viscosity soluti…

math.AP2026

On a Weiss-type Almost Monotonicity Formula

Aelson Sobral

We establish a Weiss-type almost-monotonicity formula for a broad class of variable-coefficient energy functionals, assuming only minimal regularity of the coefficients. As an appl…

math.AP2026

Fractional -caloric functions are Lipschitz

David Jesus, Aelson Sobral, José Miguel Urbano

We study the parabolic fractional Laplace equation in the degenerate range . We show that weak solutions are Lipschitz continuous…

math.AP2025

Keller-Osserman and Harnack type results for nonlinear elliptic PDE with unbounded ingredients

Boyan Sirakov, Aelson Sobral

We show that the classical Keller-Osserman theorem on the solvability of the equation is valid when is a general operator in divergence form w…

math.AP2025

Borderline regularity in singular free boundary problems

Damião J. Araújo, Aelson Sobral, Eduardo V. Teixeira +1

In this paper, we investigate the borderline regularity of local minimizers of energy functionals under minimal assumptions on the potential term . When is merely bounded an…

math.AP2024

Regularity in diffusion models with gradient activation

Damião Araújo, Aelson Sobral, Eduardo V. Teixeira

We prove sharp regularity estimates for solutions of highly degenerate fully nonlinear elliptic equations. These are free boundary models in which a nonlinear diffusion process dri…

math.AP2024

Higher regularity of solutions to fully nonlinear elliptic equations

Thialita M. Nascimento, Ginaldo Sá, Aelson Sobral +1

We establish higher regularity properties of solutions to fully nonlinear elliptic equations at interior critical points. The key novelty of our estimates lies in the fact that the…

math.AP2024

On free boundary problems shaped by varying singularities

Damião Araújo, Aelson Sobral, Eduardo V. Teixeira +1

We start the investigation of free boundary variational models featuring varying singularities. The theory depends strongly on the nature of the singular power and how it ch…

math.AP2022

Cordes-Nirenberg type results for nonlocal equations with deforming kernels

Disson dos Prazeres, Aelson Sobral, José Miguel Urbano

We derive Cordes-Nirenberg type results for nonlocal elliptic integro-differential equations with deforming kernels comparable to sections of a convex solution of a Monge-Ampère eq…