Shun-li Zhang | Searcharxiv

arXiv2002

New variable separation approach: application to nonlinear diffusion equations

The concept of the derivative-dependent functional separable solution, as a generalization to the functional separable solution, is proposed. As an application, it is used to discuss the generalized nonlinear diffusion equations based on the generalized conditional symmetry approach. As a consequence, a complete list of canonical forms for such equations which admit the derivative-dependent functional separable solutions is obtained and some exact solutions to the resulting equations are described.

nlin.SI↗

arXiv2001

High dimensional Schwarzian derivatives and Painlevé integrable models

Because of all the known integrable models possess Schwarzian forms with Möbious transformation invariance, it may be one of the best way to find new integrable models starting from some suitable Möbious transformation invariant equations. In this paper, the truncated Painlevé analysis is used to find high dimensional Schwarzian derivatives. Especially, a three dimensional Schwarzian derivative is obtained explicitly. The higher dimensional higher order Schwarzian derivatives which are invariant under the Möbious transformations may be expressed by means of the lower dimensional lower order ones. All the known Schwarzian derivatives can be used to construct high dimensional Painlevé integrable models.

nlin.SI↗