Turkish Journal of Mathematics
DOI
10.3906/mat-1912-82
Abstract
We study the following partial differential equation (PDE) \begin{align} \begin{split} (-\Delta)^s u + g(x,u) & = \mu\,\,\mbox{in}\,\,\Omega,\\ u & = 0\,\,\mbox{in}\,\,\mathbb{R}^N\setminus\Omega,\label{eqn_abs} \end{split} \end{align} where $(-\Delta)^s$ is the fractional Laplacian operator, $\Omega$ is a bounded domain in $\mathbb{R}^N$ with $\partial\Omega$ being the boundary of $\Omega$, $g(.,.)$ is a nonlinear function defined over $\Omega\times\mathbb{R}$. Let $(\mu_n)_n$ be a sequence of measure in $\Omega$. Assume that there exists a solution $u_n$ with data $\mu_n$, i.e. $u_n$ satisfies the equation (0.1) with $\mu=\mu_n$. We further assume that the sequence of measures weakly converges to $\mu$, while $(u_n)_n$ converges to $u$ in $L^1(\Omega)$. In general, $u$ is not a solution to the partial differential equation in (0.1) with datum $(\mu,0)$. However, there exists a measure $\mu^{\#}$ such that $u$ is a solution of the partial differential equation with this data. $\mu^{\#}$ is called the reduced limit of the sequence $(\mu_n)_n$. We investigate the relation between weak limit $\mu$ and the reduced limit $\mu^{\#}$ and the dependence of $\mu^{\#}$ to the sequence $(\mu_n)_n$. A closely related problem was studied by Bhakta and Marcus [3] and then by Giri and Choudhuri [15] but for the case of a Laplacian and a general second order linear elliptic differential operator, respectively instead of a fractional Laplacian.
Keywords
Fractional Laplacian, reduced limit, very weak solution, good measure, Sobolev space
First Page
2108
Last Page
2125
Recommended Citation
GIRI, RATAN KUMAR and CHOUDHURI, DEBAJYOTI
(2021)
"Reduced limit approach to semilinear PDEs involving the fractional Laplacian with measure data,"
Turkish Journal of Mathematics: Vol. 45:
No.
5, Article 16.
https://doi.org/10.3906/mat-1912-82
Available at:
https://journals.tubitak.gov.tr/math/vol45/iss5/16