Hybrid high-order methods for the wave equation on unfitted meshes

We design and analyze an unfitted hybrid high-order (HHO)
method for the acoustic wave equation. The wave propagates in a domain where a
curved interface separates subdomains with different material properties.
The key feature of the space discretization method is that the interface can cut
more or less arbitrarily through the mesh cells. We address both the
second-order formulation in time of the wave equation and its reformulation as
a first-order system.