2 papers
math.SP2026
Sum rules and a second order Feynman-Hellman theorem for abstract operators with applications
Joachim Stubbe
We discuss the role of the Feynman-Hellmann theorem for abstract one-parameter families of Hamiltonians in sum rules and trace identities of Harrell and the author and its applicat…
math.SP2025
Semiclassical eigenvalue bounds for compact homogeneous irreducible Riemannian manifolds
Luigi Provenzano, Joachim Stubbe
We exploit an identity for the gradients of Laplacian eigenfunctions on compact homogeneous Riemannian manifolds with irreducible linear isotropy group to obtain asymptotically sha…