Correct Solvability, Embedding Theorems and Separability for the Sturm-Liouville Equation

We consider the equation - y"(x)+q(x)y(x)=f(x), x\in R and the weighted function space S_p^{(2)}(R,q)=\{y\in AC_{\loc}^{(1)}(R):\|y"-qy\|_p+\|q^{1/p}y\|_p<\infty\}; p\in[1,\infty), f\in L_p(R)$and$0\le q\in L_1^{\loc}(R)$. We show that there exists an embedding S_p^{(2)}(R,q)\hookrightarrow L_p(R) if and only if equation above is correctly solvable in$L_p(R).