19.11.2025, 13:00 Uhr
– Haus 9, Raum 2.22
Forschungsseminar Diskrete Spektraltheorie
Calculus of variations for nonlocal Sobolev–Bregman forms
Artur Rutkowski
Christian Bär
We study the spectral properties of curl, a linear differential operator of first order acting on differential forms of appropriate degree on an odd-dimensional closed oriented Riemannian manifold. In three dimensions its eigenvalues are the electromagnetic oscillation frequencies in vacuum without external sources. In general, the spectrum consists of the eigenvalue 0 with infinite multiplicity and further real discrete eigenvalues of finite multiplicity. We compute the Weyl asymptotics and study the zeta-function. We give a sharp lower eigenvalue bound for positively curved manifolds and analyze the equality case. Finally, we compute the spectrum for flat tori, round spheres and spherical space forms.