Alber, Mark S.; Camassa, Roberto; Holm, Darryl D.; Marsden, Jerrold E. On the link between umbilic geodesics and soliton solutions of nonlinear PDEs. (English) Zbl 0835.35125 Proc. R. Soc. Lond., Ser. A 450, No. 1940, 677-692 (1995). Summary: We describe a new class of soliton solutions, called umbilic solitons, for certain nonlinear integrable PDEs. These umbilic solitions have the property that as the space variable \(x\) tends to infinity, the solution tends to a periodic wave, and as \(x\) tends to minus infinity, it tends to a phase shifted wave of the same shape. The equations admitting solutions in this new class include the Dym equation and equations in its hierarchy. The methods used to find and analyze these solutions are those of algebraic and complex geometry. We look for classes of solutions by constructing associated finite-dimensional integrable Hamiltonian systems on Riemann surfaces.In particular, in this setting we use geodesics on \(n\)-dimensional quadrics to find the spatial, or \(x\)-flow, which, together with the commuting \(t\)-flow given by the equation itself, defines new classes of solutions. Amongst these geodesics, particularly interesting ones are the umbilic geodesics which then generate the class of umbilic soliton solutions. This same setting also enables us to introduce another class of solutions of Dym-like equations, which are related to elliptic and umbilic billiards. Cited in 23 Documents MSC: 35Q53 KdV equations (Korteweg-de Vries equations) 37J35 Completely integrable finite-dimensional Hamiltonian systems, integration methods, integrability tests 37K10 Completely integrable infinite-dimensional Hamiltonian and Lagrangian systems, integration methods, integrability tests, integrable hierarchies (KdV, KP, Toda, etc.) 35Q51 Soliton equations Keywords:umbilic solitons; Dym equation; Hamiltonian systems on Riemann surfaces; umbilic geodesics; umbilic billiards PDFBibTeX XMLCite \textit{M. S. Alber} et al., Proc. R. Soc. Lond., Ser. A 450, No. 1940, 677--692 (1995; Zbl 0835.35125) Full Text: DOI