On self-adjoint boundary conditions for singular Sturm-Liouville operators bounded from below

Fritz Gesztesy, Lance L. Littlejohn, Roger Nichols

We extend the classical boundary values \begin{align*} & g(a) = - W(u_{a}(λ_0,.), g)(a) = \lim_{x \downarrow a} \frac{g(x)}{\hat u_{a}(λ_0,x)}, \\ &g^{[1]}(a) = (p g')(a) = W(\hat…