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Uniqueness for fractional nonsymmetric diffusion equations and an application to an inverse source problem

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 Added by Zhiyuan Li
 Publication date 2021
  fields
and research's language is English




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In this paper, we discuss the uniqueness for solution to time-fractional diffusion equation $partial_t^alpha (u-u_0) + Au=0$ with the homogeneous Dirichlet boundary condition, where an elliptic operator $-A$ is not necessarily symmetric. We prove that the solution is identically zero if its normal derivative with respect to the operator $A$ vanishes on an arbitrary small part of the spatial domain over a time interval. The proof is based on the Laplace transform and the spectral decomposition, and is valid for more general time-fractional partial differential equations, including those involving non symmetric operators.



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