Proceedings of the American Mathematical Society · 1974 · 19 citations · 6 references
Natural SciencesMathematicsPhysicsDifferential EquationsDiscrete MathematicsMathematical PhysicsBoundary-value ProblemsDiscrete-time Stochastic ProcessesExistence TheoremsExistence TheoryInitial Value ProblemsUniqueness TheoryCauchy ProblemUniqueness In Systems Of Differential EquationsUniqueness Of SolutionsUniqueness TheoremsUniqueness Theorems For Partial Differential Equations
The concatenation method, recently applied to the study of solvability and hypoellipticity of linear partial differential equations with double characteristics, is used to show that uniqueness in the Cauchy problem, for certain degenerate hyperbolic equations, depends on whether the lower order terms (precisely, the subprincipal part) assume or not certain values belonging to a sequence of complex numbers.
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