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Theory of perturbation of electric potential by a 3D object made of an anisotropic dielectric material

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 Added by Akhlesh Lakhtakia
 Publication date 2021
  fields Physics
and research's language is English




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The extended boundary condition method (EBCM) was formulated for the perturbation of a source electric potential by a 3D object composed of a homogeneous anisotropic dielectric medium whose relative permittivity dyadic is positive definite. The formulation required the application of Greens second identity to the exterior region to deduce the electrostatic counterpart of the Ewald--Oseen extinction theorem. The electric potential inside the object was represented using a basis obtained by implementing an affine bijective transformation of space to the Gauss equation for the electric field. The EBCM yields a transition matrix that depends on the geometry and the composition of the 3D object, but not on the source potential.



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167 - Lili Yan 2021
We prove that a continuous potential $q$ can be constructively determined from the knowledge of the Dirichlet-to-Neumann map for the perturbed biharmonic operator $Delta_g^2+q$ on a conformally transversally anisotropic Riemannian manifold of dimension $ge 3$ with boundary, assuming that the geodesic ray transform on the transversal manifold is constructively invertible. This is a constructive counterpart of the uniqueness result of [51]. In particular, our result is applicable and new in the case of smooth bounded domains in the $3$-dimensional Euclidean space as well as in the case of $3$-dimensional admissible manifolds.
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