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Separation of variables in an asymmetric cyclidic coordinate system
Published
Author(s)
Howard S. Cohl, Hans Volkmer
Abstract
A global analysis is presented of solutions for Laplace's equation on three-dimensional Euclidean space in one of the most general orthogonal asymmetric confocal cyclidic coordinate system which admits solutions through separation of variables. We refer to this coordinate system as five- cyclide coordinates since the coordinate surfaces are given by two confocal cyclides of genus zero, a cyclide of genus one, and two disconnected cyclides of genus zero. This coordinate system is obtained by stereographic projection of sphero-conal coordinates on four-dimensional Euclidean space. The harmonics in this coordinate system are given by products of solutions of second-order Fuchsian ordinary differential equations with five elementary singularities. The Dirichlet problem for the global harmonics in this coordinate system is solved using multiparameter spectral theory in the regions bounded by the asymmetric confocal cyclidic coordinate surfaces.
Cohl, H.
and Volkmer, H.
(2013),
Separation of variables in an asymmetric cyclidic coordinate system, Journal of Mathematical Physics, [online], https://doi.org/10.1063/1.4812321
(Accessed October 13, 2025)