The Calderón Problem for Quasilinear Conductivities of Conformally Transversally Anisotropic Media
Xi Chen, Ziyun Jin
TL;DR
This work extends Calderón’s inverse boundary value problem to quasilinear anisotropic conductivities on conformally transversally anisotropic (CTA) manifolds. It develops a higher-order linearization framework combined with complex geometric optics (CGO) and Gaussian beam constructions on CTA geometries to recover the derivatives $\partial_{(s,p)}^{\beta} a(s,x,p)$ at $(s,p)=(t,0)$ from boundary measurements; in particular, all derivatives are determined, and if $a$ is analytic in $p$, the full nonlinear conductivity is uniquely recovered. The analysis reduces the nonlinear inverse problem to linear inverse problems and leverages CTA structure to obtain uniqueness via CGO/Gaussian beams, including forward problem well-posedness and gauge invariance. Overall, the paper broadens Calderón-type identifiability to nonlinear, anisotropic media in CTA settings, providing theoretical foundations for boundary-based reconstruction in more complex EIT-like models.
Abstract
This paper investigates Calderón's problem on a conformally transversally anisotropic manifold $ (M,g) $ of dimension $n \geq 3$, where the conductivity $ a(s,x,p) $ might depend on both the electric potential and the electric field. We establish that for all $(t,x)\in \mathbb{R}\times M$ and $β\in \mathbb{N}^{1+n}$ the derivatives $ \partial_{(s,p)}^βa(s,x,p)|_{(s,p)=(t,0)}$ are uniquely determined by the boundary voltage-current measurements. If $ a(s,x,p) $ is analytic in $ p $, then $ a(s,x,p) $ can be uniquely recovered.
