Search results for "Dirichlet-to-Neumann map"

showing 4 items of 4 documents

Recovery of time-dependent coefficients from boundary data for hyperbolic equations

2019

We study uniqueness of the recovery of a time-dependent magnetic vector-valued potential and an electric scalar-valued potential on a Riemannian manifold from the knowledge of the Dirichlet to Neumann map of a hyperbolic equation. The Cauchy data is observed on time-like parts of the space-time boundary and uniqueness is proved up to the natural gauge for the problem. The proof is based on Gaussian beams and inversion of the light ray transform on Lorentzian manifolds under the assumptions that the Lorentzian manifold is a product of a Riemannian manifold with a time interval and that the geodesic ray transform is invertible on the Riemannian manifold.

GeodesicDirichlet-to-Neumann maplight ray transformmagnetic potentialBoundary (topology)CALDERON PROBLEM01 natural sciencesGaussian beamMathematics - Analysis of PDEsFOS: Mathematics111 Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]Uniqueness0101 mathematicsMathematics::Symplectic GeometryMathematical PhysicsMathematicsX-ray transformSTABILITYinverse problemsMathematical analysisStatistical and Nonlinear PhysicsRiemannian manifoldX-RAY TRANSFORMWave equationMathematics::Geometric TopologyManifoldTENSOR-FIELDS010101 applied mathematicsUNIQUE CONTINUATIONGeometry and TopologyMathematics::Differential GeometryWAVE-EQUATIONSHyperbolic partial differential equationAnalysis of PDEs (math.AP)
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Applications of Microlocal Analysis in Inverse Problems

2020

This note reviews certain classical applications of microlocal analysis in inverse problems. The text is based on lecture notes for a postgraduate level minicourse on applications of microlocal analysis in inverse problems, given in Helsinki and Shanghai in June 2019.

radon transformRadon transforminverse problemsGeneral Mathematicslcsh:Mathematics010102 general mathematicscalderón problemMicrolocal analysisDirichlet-to-Neumann mapInverse problemlcsh:QA1-93901 natural sciencesinversio-ongelmatGel’fand problem010104 statistics & probabilitymicrolocal analysisComputer Science (miscellaneous)Calculus0101 mathematicsPostgraduate levelEngineering (miscellaneous)MathematicsMathematics
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Reconstruction from boundary measurements for less regular conductivities

2012

In this paper, following Nachman's idea and Haberman and Tataru's idea, we reconstruct $C^1$ conductivity $\gamma$ or Lipchitz conductivity $\gamma$ with small enough value of $|\nabla log\gamma|$ in a Lipschitz domain $\Omega$ from the Dirichlet-to-Neumann map $\Lambda_{\gamma}$. In the appendix the authors and R. M. Brown recover the gradient of a $C^1$-conductivity at the boundary of a Lipschitz domain from the Dirichlet-to-Neumann map $\Lambda_{\gamma}$.

Mathematics - Analysis of PDEs35R30Inverse conductivity problemCalderón problemAstrophysics::High Energy Astrophysical PhenomenaBourgain's spaceFOS: MathematicsMathematics::Analysis of PDEsDirichlet-to-Neumann mapMathematics::Spectral TheoryBoundary integral equationAnalysis of PDEs (math.AP)
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Inverse problems for $p$-Laplace type equations under monotonicity assumptions

2016

We consider inverse problems for $p$-Laplace type equations under monotonicity assumptions. In two dimensions, we show that any two conductivities satisfying $\sigma_1 \geq \sigma_2$ and having the same nonlinear Dirichlet-to-Neumann map must be identical. The proof is based on a monotonicity inequality and the unique continuation principle for $p$-Laplace type equations. In higher dimensions, where unique continuation is not known, we obtain a similar result for conductivities close to constant.

010101 applied mathematicsunique continuation principleMathematics - Analysis of PDEsinverse problems010102 general mathematicsFOS: MathematicsDirichlet-to-Neumann map35J92 35R300101 mathematics01 natural sciencesp-Laplace equationinversio-ongelmatAnalysis of PDEs (math.AP)
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