5 papers
Reverse Transportation and Harnack Inequalities for Underdamped Langevin in the Non-convex Setting
Andreas Habring, Laurenz Nagler
We establish a dimension-free long-time reverse transportation, respectively Harnack inequality for the underdamped Langevin dynamics with non-convex potential. Specifically, we pr…
Annealed Underdamped Langevin Dynamics
Laurenz Nagler, Alexander Falk, Andreas Habring
In sampling, different flavours of annealing, tempering, or other successive approximation approaches are widely used and studied. In this work we investigate annealed underdamped…
Product-of-Gaussian-Mixture Diffusion Models for Joint Nonlinear MRI Reconstruction
Laurenz Nagler, Martin Zach, Thomas Pock
Recently, diffusion models have attracted considerable attention for magnetic resonance image reconstruction due to their high sample quality. However, most existing methods rely o…
Time-Inhomogeneous Preconditioned Langevin Dynamics
Alexander Falk, Laurenz Nagler, Andreas Habring +1
Langevin sampling from distributions of the form faces two major challenges: (global) mode coverage and (local) mode exploration. The first challenge is…
Product of Gaussian Mixture Diffusion Model for non-linear MRI Inversion
Laurenz Nagler, Martin Zach, Thomas Pock
Diffusion models have recently shown remarkable results in magnetic resonance imaging reconstruction. However, the employed networks typically are black-box estimators of the (smoo…