Fundamental solutions for Schrodinger operators with general inverse square potentials
In this paper, we classify the fundamental solutions for a class of Schrodinger operators.
arXiv subjects
Publications and source records attributed to Huyuan Chen.
In this paper, we classify the fundamental solutions for a class of Schrodinger operators.
Our purpose of this paper is to study the isolated singularities of positive solutions to Choquard equation in the sublinear case $q \in (0,1)$ $$\displaystyle \ \ -Δu+ u =I_α[u^p] u^q\;\; {\rm in}\; \mathbb{R}^N\setminus\{0\}, % [2mm] \phantom{ } \;\; \displaystyle \lim_{|x|\to+\infty}u(x)=0, $$ where $p >0, N \geq 3, α\in (0,N)$ and $I_α[u^p](x) = \int_{\mathbb{R}^N} \frac{u^p(y)}{|x-y|^{N-α}}dy$ is the Riesz potential, which appears as a nonlocal term in the equation. We investigate the nonexistence and existence of isolated singular solutions of Choquard equation under different range of the pair of exponent $(p,q)$. Furthermore, we obtain qualitative properties for the minimal singular solutions of the equation.
In this paper, we consider the solutions for elliptic equations involving regional fractional Laplacian \begin{equation}\label{0} \arraycolsep=1pt \begin{array}{lll} \displaystyle (-Δ)^α_Ωu=f \qquad & {\rm in}\quad Ω,\\[2mm] \phantom{ (-Δ)^α} \displaystyle u=g\quad & {\rm on}\quad \partial Ω, \end{array} \end{equation} where $Ω$ is a bounded open domain in $\mathbb{R}^N$ ($N\ge 2$) with $C^2$ boundary $\partialΩ$, $α\in(\frac12,1)$ and the operator $(-Δ)^α_Ω$ denotes the regional fractional Laplacian. We prove that when $g\equiv0$, problem (\ref{0}) admits a unique weak solution in the cases that $f\in L^2(Ω)$, $f\in L^1(Ω, ρ^βdx)$ and $f\in \mathcal{M}(Ω,ρ^β)$, here $ρ(x)={\rm dist}(x,\partialΩ)$, $β=2α-1$ and $\mathcal{M}(Ω,ρ^β)$ is a space of all Radon measures $ν$ satisfying $\int_Ωρ^βd|ν|<+\infty.$ Finally, we provide an Integral by Parts Formula for the classical solution of (\ref{0}) with general boundary data $g$.
Our purpose of this paper is to study the nonexistence of nonnegative very weak solutions of \begin{equation}\label{eq 0.1} \displaystyle (-Δ)^αu = u^p+ν\quad {\rm in}\quad Ω,\qquad\ u=g\quad {\rm in}\quad \mathbb{ R}^N\setminus Ω, \end{equation} where $α\in(0,1)$, $p>0$, $Ω$ is a unbounded $C^2$ domain in $\mathbb{ R}^N$ with $N>2α$, $g\in L^1(\mathbb{ R}^N\setminus Ω,\frac{dx}{1+|x|^{N+2α}})$ nonnegative and $ν$ is a nonnegative Radon measure. We obtain that\smallskip $(i)$ if $Ω\supseteq \left(\mathbb{R}^N\setminus \overline{B_{r_0}(0)}\right)$ for some $r_0>0$ and $p<\frac{N}{N-2α}$, then fractional Lane-Emden equation has no weak solutions. $(ii)$ if $Ω\supseteq \left\{x\in \mathbb{ R}^N:\, x\cdot a>r_0\right\}$ for some $r_0\ge 0$, $a\in \mathbb{ R}^N$ and $p<\frac{N+α}{N-α}$, then fractional Lane-Emden equation has no weak solutions. Here $\frac{N+α}{N-α}$ is sharp for the nonexistence in the half space. \smallskip The above Liouville theorem could be applied to obtain nonexistence of classical solution of the fractional Lane-Emden equations $$ (-Δ)^αu = u^p\quad {\rm in}\quad Ω, \qquad u\ge 0\quad {\rm in}\quad \mathbb{ R}^N\setminus Ω, $$ where $Ω=\mathbb{R}^N\setminus B_{r_0}(0)$ with $r_0>0$ or $Ω=\mathbb{R}^{N-1}\times(0,+\infty)$.
In this paper we classify the isolated singularities of positive solutions to Choquard equation and prove the existence of isolated singular solutions.
This paper is concerned with the nonlinear elliptic problem $-Δu=\frac{λ}{(a-u)^2}$ on a bounded domain $Ω$ of $\mathbb{R}^N$ with Dirichlet boundary conditions. This problem arises from Micro-Electromechanical Systems devices in the case that the elastic membrane contacts the ground plate on the boundary. We analyze the properties of minimal solutions to this equation when $λ>0$ and the function $a:\barΩ\to[0,1]$ satisfying $a(x)\ge κ{\rm dist}(x,\partialΩ)^γ$ for some $κ>0$ and $γ\in(0,1)$. Our results show how the boundary decay of the membrane works on the solutions and pull-in voltage $λ$.
In this paper, we classify the singularities of nonnegative solutions to fractional elliptic equation \begin{equation}\label{eq 0.1} \arraycolsep=1pt \begin{array}{lll} \displaystyle (-Δ)^αu=u^p\quad &{\rm in}\quad Ω\setminus\{0\},\\[2mm] \phantom{ (-Δ)^α} \displaystyle u=0\quad &{\rm in}\quad \mathbb{R}^N\setminusΩ, \end{array} \end{equation} where $p>1$, $Ω$ is a bounded, $C^2$ domain in $\mathbb{R}^N$ containing the origin, $N\ge2$ and the fractional Laplacian $(-Δ)^α$ is defined in the principle value sense. We obtain that any classical solution $u$ of (\ref{eq 0.1}) is a weak solution of \begin{equation}\label{eq 0.2} \arraycolsep=1pt \begin{array}{lll} \displaystyle (-Δ)^αu=u^p+kδ_0\quad &{\rm in}\quad Ω,\\[2mm] \phantom{ (-Δ)^α} \displaystyle u=0\quad &{\rm in}\quad \mathbb{R}^N\setminusΩ\end{array} \end{equation} for some $k\ge0$, where $δ_0$ is the Dirac mass at the origin. In particular, when $p\ge \frac{N}{N-2α}$, we have that $k=0$; when $p< \frac{N}{N-2α}$, $u$ has removable singularity at the origin if $k=0$ and if $k>0$, $u$ satisfies $$\lim_{x\to0} u(x)|x|^{N-2α}=c_{N,α}k,$$ where $c_{N,α}>0$. Furthermore, when $p\in(1, \frac{N}{N-2α})$, we obtain that there exists $k^*>0$ such that problem (\ref{eq 0.1}) has at least two positive solutions for $k k^*$.
In this paper, we study the following elliptic problem with Dirac mass \begin{equation}\label{eq 0.1} -Δu=Vu^p+k δ_0\quad {\rm in}\quad \mathbb{R}^N, \qquad \lim_{|x|\to+\infty}u(x)=0, \end{equation} where $N>2$, $p>0$, $k>0$, $δ_0$ is Dirac mass at the origin, the function $V$ is a locally Lipchitz continuous in $\mathbb{R}^N\setminus\{0\}$ satisfying $$ V(x)\le \frac{c_1}{|x|^{a_0}(1+|x|^{a_\infty-a_0})} $$ with $a_0 a_0 $ and $c_1>0$. We obtain two positive solutions of (\ref{eq 0.1}) with additional conditions for parameters on $a_\infty, a_0$, $p$ and $k$. The first solution is a minimal positive solution and the second solution is constructed by Mountain Pass theorem.
We study existence and uniqueness of weak solutions to (F) $\partial\_t u+ (-Δ)^\alphau+h(t, u)=0 $ in $(0,\infty)\times\R^N$,with initial condition $u(0,\cdot)=ν$ in $\R^N$, where $N\ge2$, the operator $(-Δ)^α$is the fractional Laplacian with $α\in(0,1)$, $ν$ isa bounded Radon measure and $h:(0,\infty)\times\R\to\R$ is a continuous function satisfying a subcritical integrability condition.In particular, if $h(t,u)=t^βu^p$ with $β\textgreater{}-1$ and $0 \textless{} p \textless{} p^*\_β:=1+\frac{2α(1+β)}{N}$, we prove that there exists a unique weak solution $u\_k$ to (F) with $ν=kδ\_0$, where $δ\_0$ is the Dirac mass at the origin. We obtain that $u\_k\to\infty$ in $(0,\infty)\times\R^N$ as $k\to\infty$ for $p\in(0,1]$ and the limit of $u\_k$ exists as $k\to\infty$ when $1 \textless{} p \textless{} p^*\_β$, we denote it by $u\_\infty$.When $1+\frac{2α(1+β)}{N+2α}:=p^{**}\_β\textless{} p \textless{} p^*\_β$,$u\_\infty$ is the minimal self-similar solution of $(F)\_\infty$ $\partial\_t u+ (-Δ)^αu+t^βu^p=0 $ in $(0,\infty)\times\R^N$ with the initial condition $u(0,\cdot)=0$ in $\R^N\setminus\{0\}$ and it satisfies $u\_\infty(0,x)=0$ for $x\neq 0$.While if $1\textless{} p \textless{} p^{**}\_β$, then $u\_\infty\equiv U\_p$, where $U\_p$ is the maximal solution of the differential equation $y'+t^βy^p=0$ on $\R\_+$.
The purpose of this article is to give a complete study of the weak solutions of the fractional elliptic equation \begin{equation}\label{00} \arraycolsep=1pt \begin{array}{lll} (-Δ)^α u+u^p=0\ \ \ \ &\ {\rm in}\ \ B_1(e_N),\\[2mm]\phantom{(-Δ)^α +u^p} u=δ_{0}& \ {\rm in}\ \ \mathbb{R}^N\setminus B_1(e_N), \end{array} \end{equation} where $p>0$, $ (-Δ)^α$ with $α\in(0,1)$ denotes the fractional Laplacian operator in the principle value sense, $B_1(e_N)$ is the unit ball centered at $e_N=(0,\cdots,0,1)$ in $\mathbb{R}^N$ with $N\ge 2$ and $δ_0$ is the Dirac mass concentrated at the origin. We prove that problem (\ref{00}) admits a unique weak solution when $p> 1+\frac{2α}{N}$. Moreover, if in addition $p\ge \frac{N+2}{N-2}$, the weak solution vanishes as $α\to 1^-$. We also show that problem (\ref{00}) doesn't have any weak solution when $p\in[0, 1+\frac{2α}{N}]$. These results are very surprising since there are in total contradiction with the classical setting, i.e. $$ \arraycolsep=1pt \begin{array}{lll} -Δu+ u^p=0\ \ \ \ &\ {\rm in}\ \B_1(e_N),\\[2mm] \phantom{-Δ+u^{p} } u=δ_{0}& \ {\rm in}\ \ \R^N\setminus B_1(e_N), \end{array} $$ for which it has been proved that there are no solutions for $p\ge \frac{N+1}{N-1}$.
Let $α\in(0,1)$, $Ω$ be a bounded open domain in $R^N$ ($N\ge 2$) with $C^2$ boundary $\partialΩ$ and $ω$ be the Hausdorff measure on $\partialΩ$. We denote by $\frac{\partial^αω}{\partial \vec{n}^α}$ a measure $$\langle\frac{\partial^αω}{\partial \vec{n}^α},f\rangle=\int_{\partialΩ}\frac{\partial^αf(x)}{\partial \vec{n}_x^α} dω(x),\quad f\in C^1(\barΩ),$$ where $\vec{n}_x$ is the unit outward normal vector at point $x\in\partialΩ$. In this paper, we prove that problem $$ \begin{array}{lll} (-Δ)^αu+g(u)=k\frac{\partial^αω}{\partial \vec{n}^α}\quad & {\rm in}\quad \barΩ,\\[2mm] \phantom{(-Δ)^α+g(u)} u=0\quad & {\rm in}\quad Ω^c \end{array} $$ admits a unique weak solution $u_k$ under the hypotheses that $k>0$, $(-Δ)^α$ denotes the fractional Laplacian with $α\in(0,1)$ and $g$ is a nondecreasing function satisfying extra conditions. We prove that the weak solution is a classical solution of $$ \begin{array}{lll} \ \ \ (-Δ)^αu+g(u)=0\quad & {\rm in}\quad Ω,\\[2mm] \phantom{------\} \ u=0\quad & {\rm in}\quad R^N\setminus\barΩ,\\[2mm] \phantom{} \lim_{x\inΩ,x\to\partialΩ}u(x)=+\infty. \end{array} $$
The purpose of this paper is to study the weak solutions of the fractional elliptic problem \begin{equation}\label{000} \begin{array}{lll} (-Δ)^αu+εg(u)=k\frac{\partial^αν}{\partial \vec{n}^α}\quad &{\rm in}\quad\ \ \barΩ,\\[3mm] \phantom{(-Δ)^α+εg(u)} u=0\quad &{\rm in}\quad\ \ \barΩ^c, \end{array} \end{equation} where $k>0$, $ε=1$ or $-1$, $(-Δ)^α$ with $α\in(0,1)$ is the fractional Laplacian defined in the principle value sense, $Ω$ is a bounded $C^2$ open set in $R^N$ with $N\ge 2$, $ν$ is a bounded Radon measure supported in $\partialΩ$ and $\frac{\partial^αν}{\partial \vec{n}^α}$ is defined in the distribution sense, i.e. $$ \langle\frac{\partial^αν}{\partial \vec{n}^α},ζ\rangle=\int_{\partialΩ}\frac{\partial^αζ(x)}{\partial \vec{n}_x^α}dν(x), \qquad \forallζ\in C^α(R^N), $$ here $\vec{n}_x$ denotes the unit inward normal vector at $x\in\partialΩ$.
In this article, we study the existence of positive solutions to elliptic equation (E1) $$(-Δ)^αu=g(u)+σν\quad{\rm in}\quad Ω,$$ subject to the condition (E2) $$u=\varrhoμ\quad {\rm on}\quad \partialΩ \ {\rm if}\ α=1\qquad {\rm or\ \ in}\ \ Ω^c \ \ {\rm if}\ α\in(0,1),$$ where $σ,\varrho\ge0$, $Ω$ is an open bounded $C^2$ domain in $\mathbb{R}^N$, $(-Δ)^α$ denotes the fractional Laplacian with $α\in(0,1)$ or Laplacian operator if $α=1$, $ν,μ$ are suitable Radon measures and $g:\mathbb{R}_+\mapsto\mathbb{R}_+$ is a continuous function. We introduce an approach to obtain weak solutions for problem (E1)-(E2) when $g$ is integral subcritical and $σ,\varrho\ge0$ small enough.
The purpose of this paper is to extend the embedding theorem of Sobolev spaces involving general kernels and we provide a sharp critical exponent in these embeddings. As an application, solutions for equations driven by a general integro-differential operator, with homogeneous Dirichlet boundary conditions, is established by using the Mountain Pass Theorem.
In this paper, we study the existence of nonnegative weak solutions to (E) $ (-Δ)^αu+h(u)=ν$ in a general regular domain $Ω$, which vanish in $\R^N\setminusΩ$, where $(-Δ)^α$ denotes the fractional Laplacian with $α\in(0,1)$, $ν$ is a nonnegative Radon measure and $h:\mathbb{R}_+\to\mathbb{R}_+$ is a continuous nondecreasing function satisfying a subcritical integrability condition. Furthermore, we analyze properties of weak solution $u_k$ to $(E)$ with $Ω=\mathbb{R}^N$, $ν=kδ_0$ and $h(s)=s^p$, where $k>0$, $p\in(0,\frac{N}{N-2α})$ and $δ_0$ denotes Dirac mass at the origin. Finally, we show for $p\in(0,1+\frac{2α}{N}]$ that $u_k\to\infty$ in $\mathbb{R}^N$ as $k\to\infty$, and for $p\in(1+\frac{2α}{N},\frac{N}{N-2α})$ that $\lim_{k\to\infty}u_k(x)=c|x|^{-\frac{2α}{p-1}}$ with $c>0$, which is a classical solution of $ (-Δ)^αu+u^p=0$ in $\mathbb{R}^N\setminus\{0\}$.
Let $p\in(0,\frac{N}{N-2α})$, $α\in(0,1)$ and $Ω\subset \R^N$ be a bounded $C^2$ domain containing $0$. If $δ_0$ is the Dirac measure at $0$ and $k>0$, we prove that the weakly singular solution $u_k$ of $(E_k)$ $ (-Δ)^αu+u^p=kδ_0 $ in $Ω$ which vanishes in $Ω^c$, is a classical solution of $(E_*)$ $ (-Δ)^αu+u^p=0 $ in $Ω\setminus\{0\}$ with the same outer data. When $\frac{2α}{N-2α}\leq 1+\frac{2α}{N}$, $p\in(0, 1+\frac{2α}{N}]$ we show that the $u_k$ converges to $\infty$ in whole $Ω$ when $k\to\infty$, while, for $p\in(1+\frac{2α}N,\frac{N}{N-2α})$, the limit of the $u_k$ is a strongly singular solution of $(E_*)$. The same result holds in the case $1+\frac{2α}{N}<\frac{2α}{N-2α}$ excepted if $\frac{2α}{N}
We study the existence of solutions to the fractional elliptic equation (E1) $(-Δ)^αu+εg(|\nabla u|)=ν$ in a bounded regular domain $Ω$ of $\R^N (N\ge2)$, subject to the condition (E2) $u=0$ in $Ω^c$, where $ε=1$ or $-1$, $(-Δ)^α$ denotes the fractional Laplacian with $α\in(1/2,1)$, $ν$ is a Radon measure and $g:\R_+\mapsto\R_+$ is a continuous function. We prove the existence of weak solutions for problem (E1)-(E2) when $g$ is subcritical. Furthermore, the asymptotic behavior and uniqueness of solutions are described when $ν$ is Dirac mass, $g(s)=s^p$, $p\geq 1$ and $ε=1$.
In this paper we study positive solutions to problem involving the fractional Laplacian $(E)$ $(-Δ)^α u(x)+|u|^{p-1}u(x)=0 in x\inΩ\setminus\mathcal{C}$, subject to the conditions $u(x)=0$ $x\inΩ^c$ and $\lim_{x\inΩ\setminus\mathcal{C}, x\to\mathcal{C}}u(x)=+\infty$, where $p>1$ and $Ω$ is an open bounded $C^2$ domain in $\mathbb{R}^N$, $\mathcal{C}\subset Ω$ is a compact $C^2$ manifold with $N-1$ multiples dimensions and without boundary, the operator $(-Δ)^α$ with $α\in(0,1)$ is the fractional Laplacian. We consider the existence of positive solutions for problem $(E)$. Moreover, we further analyze uniqueness, asymptotic behaviour and nonexistence.