The elliptic sinh-Gordon equation in the half plane
Authors
Guenbo Hwang
- Department of Mathematics, Daegu University, Gyeongsan Gyeongbuk 712-714, Korea
Abstract
Boundary value problems for the elliptic sinh-Gordon equation formulated in the half plane are studied
by applying the so-called Fokas method. The method is a significant extension of the inverse scattering
transform, based on the analysis of the Lax pair formulation and the global relation that involves all known
and unknown boundary values. In this paper, we derive the formal representation of the solution in terms
of the solution of the matrix Riemann-Hilbert problem uniquely defined by the spectral functions. We also
present the global relation associated with the elliptic sinh-Gordon equation in the half plane. We in turn
show that given appropriate initial and boundary conditions, the unique solution exists provided that the
boundary values satisfy the global relation. Furthermore, we verify that the linear limit of the solution
coincides with that of the linearized equation known as the modified Helmhotz equation.
Keywords
- Boundary value problems
- elliptic PDEs
- sinh-Gordon equation
- integrable equation.
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