collaborators

12 papers

math.AP2026

Generic Recovery of Permittivity and Permeability in Anisotropic Maxwell Systems

Antonio Cocan, Maarten V. de Hoop, Joonas Ilmavirta +3

We study the inverse problem of recovering the constitutive tensors of a homogeneous anisotropic electromagnetic medium without magnetoelectric coupling (non-chiral) from its Fresn…

math.AG2026

Classification of singularities of planar slowness surfaces

Antonio Cocan, Maarten V. de Hoop, Joonas Ilmavirta +2

Slowness surfaces are algebraic varieties arising from propagation of elastic waves. In dimensions , we completely classify the types of singularities slowness surfaces can have…

math.MG2026

Stable recovery of a simple irreversible Finsler geometry from travel time data

Maarten V. de Hoop, Joonas Ilmavirta, Antti Kykkänen +1

We show that a simple irreversible Finsler geometry can be recovered uniquely and Lipschitz-stably from its travel time data. We introduce and use a version of Gromov--Hausdorff di…

math.AP2026

Rigidity of homogeneous Lamé systems

Joonas Ilmavirta, Teemu Saksala, Lili Yan

In this short paper, we show that any Lamé system whose Dirichlet-to-Neumann map for the elastic wave equation agrees with the one arising from the homogeneous Lamé system must a…

math.DG2026

Tomography of 1-forms on a gas giant

Joonas Ilmavirta, Antti Kykkänen, Eetu Satukangas

We show that on gas giant manifolds the geodesic X-ray transform is solenoidally injective on one-forms that are smooth up to the boundary in an appropriate smooth structure. A gas…

math.DG2025

Horizontal and Vertical Regularity of Elastic Wave Geometry

Joonas Ilmavirta, Pieti Kirkkopelto, Antti Kykkänen

The elastic properties of a material are encoded in a stiffness tensor field and the propagation of elastic waves is modeled by the elastic wave equation. We characterize analytic…