The cubic vortical Whitham equation is a model for wave motion on vertically sheared current of constant vorticity in shallow inviscid fluid. It generalizes the classical by allowing and adding nonlinear term. inclusion this extra term allows to admit periodic, traveling-wave solutions with larger amplitude than equation. Increasing leads as well. stability these examined numerically. All moder...

The Cauchy problem for the Korteweg de Vries (KdV) equation with small dispersion of order ǫ, ǫ ≪ 1, is characterized by the appearance of a zone of rapid modulated oscillations. These oscillations are approximately described by the elliptic solution of KdV where the amplitude, wave-number and frequency are not constant but evolve according to the Whitham equations. Whereas the difference betwe...

In this article, fractional complex transform with optimal homotopy analysis method (OHAM) is used to obtain numerical and analytical solutions for the nonlinear time-space fractional Fornberg-Whitham. Fractional complex transform is proposed to convert time-space fractional Fornberg-Whitham equation to the nonlinear ordinary differential equations and then applied OHAM to the new obtained equa...

A new description of the universal Whitham hierarchy in terms of a factorization problem in the Lie group of canonical transformations is provided. This scheme allows us to give a natural description of dressing transformations, string equations and additional symmetries for the Whitham hierarchy. We show how to dress any given solution and prove that any solution of the hierarchy may be undres...

Introduction. Whitham's averaged equations [1] for a nonlinear evolution system describe slow modulations of parameters on a family of periodic traveling wave solutions (or on families of multiphase quasiperiodic solutions, which are so far knows to exist only for integrable equations) and are a system of hydrodynamic type [2, 3], that is, of the form

The second derivatives of prepotential with respect to Whitham time-variables in the Seiberg-Witten theory are expressed in terms of Riemann theta-functions. These formulas give a direct transcendental generalization of algebraic ones for the Kontsevich matrix model. In particular case they provide an explicit derivation of the renormalization group (RG) equation proposed recently in papers on ...

A number of formulas are displayed concerningWhitham theory for a simple example of pure N = 2 susy Yang-Mills (YM) with gauge group SU(2). In particular this serves to illuminate the role of Λ and T1 derivatives and the interaction with prepotentials F (Seiberg-Witten) and F (Whitham).