2025/03/25 by de Hoop, Maarten V., Ilmavirta, Joonas, Katsnelson, Vitaly
#Analysis of PDEs (math.AP) #FOS: Mathematics
paper · doi:10.48550/arxiv.2503.19866
We study the inverse spectral problem of jointly recovering a radially symmetric Riemannian metric and an additional coefficient from the Dirichlet spectrum of a perturbed Laplace-Beltrami operator on a bounded domain. Specifically, we consider the elliptic operator La,b := ea-b ∇ ⋅ eb ∇ on the unit ball B ⊂ ℝ3 , where the scalar functions a = a(|x|) and b = b(|x|) are spherically symmetric and satisfy certain geometric conditions. While the function a influences the principal symbol of L , the function b appears in its first-order terms. We investigate the extent to which the Dirichlet eigenvalues of La,b uniquely determine the pair (a, b) and establish spectral rigidity results under suitable assumptions.