arXiv subjects
Publications and source records attributed to Emerson Abreu.
This paper investigates the existence, nonexistence, and qualitative properties of p-harmonic functions in the upper half-space $\mathbb{R}^N_+ \, (N \geq 3)$ satisfying nonlinear boundary conditions for $1<p<N$. Moreover, the symmetry of positive solutions is shown by using the method of moving planes.
In this work, we develop a study involving some nonlinear partial differential equations on spheres and hemispheres, with the zero Neumann boundary condition, which are so-called Brezis-Nirenberg type problems, and we give conditions on which such equations have only constant solutions. We also extend these results for some nonlinear partial differential systems.
In this paper, we obtain nonexistence results of positive solutions, and also the existence of an unbounded sequence of solutions that changing sign for some critical problems involving conformally invariant operators on the standard unit sphere, and the fractional Laplacian operator in the Euclidean space. Our arguments are based on a reduction of the initial problem in the Euclidean space to an equivalent problem on the standard unit sphere and vice versa, what together to blow up arguments, a variant of Pohozaev's type identity, a refinement of regularity results for this type operators, and finally, by exploiting the symmetries of the sphere.
We consider the monomial weight $x^{A}=\vert x_{1}\vert^{a_{1}}\ldots\vert x_{N}\vert^{a_{N}}$, where $a_{i}$ is a nonnegative real number for each $i\in\{1,\ldots,N\}$, and we establish the existence and nonexistence of isoperimetric inequalities with different monomial weights. We study positive minimizers of $\int_{\partialΩ}x^{A}\mathcal{H}^{N-1}(x)$ among all smooth bounded sets $Ω$ in $\mathbb{R}^{N}$ with fixed Lebesgue measure with monomial weight $\int_Ωx^{B}dx$.
In this paper, we consider the regularity of weak solutions (in an appropriate space) to the elliptic partial differential equation \begin{equation*} (-Δ_{p})^{s} u + (-Δ_{q})^{s} u = f(x) \quad \text{in} \quad \mathbb{R}^{N}, \end{equation*} where $0<s<1$ and $ 2 \leq q \leq p < N/s$. We prove that these solutions are locally in $C^{0,α}(\mathbb{R}^N)$, which seems to be optimal. Furthermore, we prove the existence of solutions to the problem \begin{equation*} (-Δ_{p})^{s} u + (-Δ_{q})^{s} u = \vert u \vert^{p^{*}_{s}-2}u + λg(x) \vert u \vert^{r-2}u \,\,\, \text{in} \,\,\,\, \mathbb{R}^{N}, \end{equation*} where $1 < q\leq p < N/s$, $λ$ is a parameter and $g$ satisfies some conditions of integrability. We also show that, if $g$ is bounded, then the solutions are continuous and bounded.
We establish the Trudinger-Moser inequality on weighted Sobolev spaces in the whole space, and for a class of quasilinear elliptic operators in radial form of the type $\displaystyle Lu:=-r^{-θ}(r^α\vert u'(r)\vert^βu'(r))'$, where $θ, β\geq 0$ and $α>0$, are constants satisfying some existence conditions. It worth emphasizing that these operators generalize the $p$- Laplacian and $k$-Hessian operators in the radial case. Our results involve fractional dimensions, a new weighted Pólya-Szeg{ö} principle, and a boundness value for the optimal constant in a Gagliardo-Nirenberg type inequality.