The cosh-Gordon equation is a nonlinear elliptic partial differential equation commonly normalized as
Conventions in the literature may rescale the independent variables and the dependent variable, so
constant factors in front of and hyperbolic cosine
are not intrinsic.
The cosh-Gordon equation occurs as the Gauss part of the Gauss-Codazzi equations for surfaces of constant mean curvature in hyperbolic geometry. In particular, away from zeros of the Hopf differential, the Gauss part of the Gauss-Codazzi equations of a hyperbolic minimal surface can be reduced locally to a cosh-Gordon equation by a conformal change of coordinate and normalization of the Hopf differential (Bobenko 1991).