25 papers
An inverse free boundary problem
Cătălin I. Cârstea, Matti Lassas, Jinpeng Lu +2
We study inverse problems for the elliptic and parabolic obstacle problems from boundary measurements. For the classical elliptic obstacle problem with strictly superharmonic obsta…
Multiphase-Diff: Diffusion-Based Generative Modeling for High-Contrast Multiphase Physical Systems with Sharp Interfaces
Yining Huang, Zhenyu Liang
Physics-constrained diffusion for high-contrast, sharp-interface multiphase fields faces three coupled difficulties. At coefficient jumps, expanded pointwise strong-form PDE residu…
Semiglobal uniqueness for the Lorentzian Calderón problem
Lauri Oksanen, Rakesh, Mikko Salo
We prove uniqueness in the Lorentzian Calderón problem in a semiglobal setting, comparing a potentially large perturbation of the Minkowski metric against a small one. Our proof us…
Determination of an anisotropic perturbation in elastic inverse scattering
Matti Lassas, Shiqi Ma, Lauri Oksanen +2
We consider a linearized inverse scattering problem for elastic waves. We prove that a fully anisotropic perturbation of the elastic parameters around an isotropic and homogeneous…
Counterexamples to the Lorentzian Calderón problem
Lauri Oksanen, Miika Sarkkinen
We show that two non-isometric, smooth, globally hyperbolic Lorentzian metrics can have the same hyperbolic Dirichlet-to-Neumann map on an infinite cylinder with timelike boundary.
Introduction to inverse problems for hyperbolic PDEs
Medet Nursultanov, Lauri Oksanen
There are two main approaches to solve inverse coefficient determination problems for wave equations: the Boundary Control method and an approach based on geometric optics. These n…