Inverse problems for semilinear wave equations on Lorentzian manifolds

Matti Lassas, Gunther Uhlmann, Yiran Wang

We consider inverse problems in space-time $(M,g)$, a $4$-dimensional Lorentzian manifold. For semilinear wave equations ${\square }_{g}u+H(x,u)=f$, where ${\square }_g$ denotes the…