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Uniqueness theorems for equations of Keldysh Type

Thomas H. Otway
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Abstract

A fundamental result that characterizes elliptic-hyperbolic equations of Tricomi type, the uniqueness of classical solutions to the open Dirichlet problem, is extended to a large class of elliptic-hyperbolic equations of Keldysh type. The result implies the non-existence of classical solutions to the closed Dirichlet problem for this class of equations. A uniqueness theorem is also proven for a mixed Dirichlet-Neumann problem. A generalized uniqueness theorem for the adjoint operator leads to the existence of distribution solutions to the closed Dirichlet problem in a special case.

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Thomas H. Otway. 2010-05-25. Uniqueness theorems for equations of Keldysh Type. https://arxiv.org/abs/math-ph/0606021

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