Determining Lamé coefficients by elastic Dirichlet-to-Neumann map on a Riemannian manifold

Abstract: For the Lam\'{e} operator $\mathcal{L}{\lambda,\mu}$ with variable coefficients $\lambda$ and $\mu$ on a smooth compact Riemannian manifold $(M,g)$ with smooth boundary $\partial M$, we give an explicit expression for full symbol of the elastic Dirichlet-to-Neumann map $\Lambda{\lambda,\mu}$. We show that $\Lambda_{\lambda,\mu}$ uniquely determines partial derivatives of all orders of the Lam\'{e} coefficients $\lambda$ and $\mu$ on $\partial M$. Moreover, for a nonempty open subset $\Gamma\subset\partial M$, suppose that the manifold and the Lam\'{e} coefficients are real analytic up to $\Gamma$, we prove that $\Lambda_{\lambda,\mu}$ uniquely determines the Lam\'{e} coefficients on the whole manifold $\bar{M}$.