|
Vestnik Volgogradskogo gosudarstvennogo universiteta. Seriya 1. Mathematica. Physica, 2014, Issue 2(21), Pages 17–26
(Mi vvgum42)
|
|
|
|
Mathematics
On interrelation between resolvabilities of some boundary value problems for $L$-harmonic functions on unbounded open subsets of Riemannian manifolds
S. A. Korolkov Volgograd State University
Abstract:
We study $L$-harmonic functions,
i.e. solutions of the stationary Shrodinger equation
$$Lu\equiv\Delta u-c(x)u=0$$ on unbounded open set of Riemannian manifold and
establish some existence results.
Let $M$ be a smooth connected noncompact Riemannian manifold
without boundary and $\Omega$ be a simply connected unbounded open
set of $M$ with $C^1$-smooth boundary $\partial \Omega$. Let
$\{B_k\}_{k=1}^\infty$ be a smooth exhaustion of $M$, i.e. sequence
of precompact open subsets of $M$ with $C^1$-smooth boundaries
$\partial B_k$ such that $M=\bigcup_{k=1}^\infty B_k$, $\overline
B_k\subset B_{k+1}$ for all $k$. In what follows we assume
$B_k\cap \Omega\ne\emptyset$, sets $B_k\cap\Omega$ are simply
connected, $\partial B_k$ and $\partial \Omega$ are transversal
for all $k$.
Let $B'_k=B_k \setminus\Omega$ and $v_{M\setminus B'_k}$ be a
$L$-potential of $B'_k$ relative to $M$ (see, for example,
[10; 11]). By the maximum principle, the
sequence $\{v_{M\setminus B'_k}\}_{k=1}^\infty$ is point-wise
increasing and converges to an $L$-harmonic in $\Omega$ function
$v_{\Omega}=\lim\limits_{k\to\infty}v_{M\setminus B'_k}$. It is
easy to see that $0\leq v_{\Omega}\leq 1$,
$v_\Omega|_{\partial\Omega}=1$. The function $v_{\Omega}$ is
called the $L$-potential of the $\Omega$.
Two continuous in $\Omega$ (in $\partial\Omega$, resp.) functions
$f_1$ and $f_2$ are called weak equivalent in $\Omega$
(in $\partial\Omega$, resp.) relative to $v_{\Omega}$
($f_1\stackrel{\Omega}{\simeq} f_2$,
$f_1\stackrel{\partial\Omega}{\simeq} f_2$, resp.) if there exists
some constant $C$, such that $|f_1-f_2|\leq C v_{\Omega}\rm{\; in
\;} \Omega$ ($|f_1-f_2|\leq C v_{\Omega}$ in $\partial\Omega$,
resp.).
A continuous function $f$ in $\Omega$ is called weak admissible
relative to $\Omega$ ($f\in K^*_\Omega(\Omega)$) if there is an
compact $B$ and $L$-harmonic function $u$ in $\Omega\setminus B$
such that $u\stackrel{\Omega}{\simeq} f$ in $\Omega\setminus B$.
We have the following results.
Theorem 1. Let $B$ be an compact, $v_{M\setminus B}$ be a
$L$-potential of $B$ relative to $M$ and $u(x)$ be an $L$-harmonic
in $\Omega\setminus B$ function. Then there exists a constant $C$
and $L$-harmonic in $\Omega$ function $f$ such that
$ |f-u|\leq Cv_{M\setminus B} \in{\; in \;} \Omega\setminus B.$
Theorem 2. Let $f\in K^*_\Omega(\Omega)$. Then for any
continuous in $\partial\Omega$ function $\varphi$ such that
$\varphi\stackrel{\Omega}{\simeq}f$ in $\partial\Omega$, there
exists solution of the following problem in $\Omega$
$$
\left\{ \begin{array}{c} Lu=0 \rm{\; in \;}\Omega,\\
u|_{\partial\Omega}=\varphi,\\
u\stackrel{\Omega}{\simeq}f.
\end{array} \right.
$$
Keywords:
boundary
problems, $L$-harmonic functions, Riemannian manifolds, solutions of the stationary Shrodinger equation, equivalent functions.
Citation:
S. A. Korolkov, “On interrelation between resolvabilities of some boundary value problems for $L$-harmonic functions on unbounded open subsets of Riemannian manifolds”, Vestnik Volgogradskogo gosudarstvennogo universiteta. Seriya 1. Mathematica. Physica, 2014, no. 2(21), 17–26
Linking options:
https://www.mathnet.ru/eng/vvgum42 https://www.mathnet.ru/eng/vvgum/y2014/i2/p17
|
Statistics & downloads: |
Abstract page: | 142 | Full-text PDF : | 52 | References: | 37 |
|