21 citations · 132 across the 37 of their papers we have counts for
4 papers · 1 filter
A Short Proof of the Localization Formula for the Loop Space Chern Character of Spin Manifolds
Matthias Ludewig, Zelin Yi
In this note, we give a short proof of the localization formula for the loop space Chern character of a compact Riemannian spin manifold M, using the rescaled spinor bundle on the…
Gaplessness of Landau Hamiltonians on hyperbolic half-planes via coarse geometry
Matthias Ludewig, Guo Chuan Thiang
We use coarse index methods to prove that the Landau Hamiltonian on the hyperbolic half-plane, and even on much more general imperfect half-spaces, has no spectral gaps. Thus the e…
Cobordism invariance of topological edge-following states
Matthias Ludewig, Guo Chuan Thiang
We prove that a spectral gap-filling phenomenon occurs whenever a Hamiltonian operator encounters a coarse index obstruction upon compression to a domain with boundary. Furthermore…
A Framework for Geometric Field Theories and their Classification in Dimension One
Matthias Ludewig, Augusto Stoffel
In this paper, we develop a general framework of geometric functorial field theories, meaning that all bordisms in question are endowed with geometric structures. We take particula…