Language:   Search:   Contact
Zentralblatt MATH has released its new interface!
For an improved author identification, see the new author database of ZBMATH.

Query:
Fill in the form and click »Search«...
Format:
Display: entries per page entries
Zbl 0940.35177
Constantin, A.; McKean, H.P.
A shallow water equation on the circle.
(English)
[J] Commun. Pure Appl. Math. 52, No.8, 0949-0982 (1999). ISSN 0010-3640

The purpose of this paper is to study the spatially periodic case of the shallow water equation $$\partial v/\partial t+ v\partial t/\partial x+\partial p/\partial x= 0\tag 1$$ in which the pressure'' $p$ is $(1- d^2/dx^2)^{-1}(v^2+{1\over 2} v^{\prime 2})$. The equation has been much studied in recent years, starting with {\it R. Camma} and {\it D. D. Holm} [Phys. Rev. Lett. 81, 1661-1664 (1993)] and {\it R. Camassa}, {\it D. D. Holm} and {\it J. M. Hyman} [Adv. Appl. Math. 31, 1-33 (1994; Zbl 0808.76011)]. It is notable for a) its complete integrability, b) the existence of peaked solitons and the simplicity of their superposition, c) the presence of breaking waves (blow-up), and d) the equivalence of the flow to the geodesic flow on the group of (compressible) diffeomorphisms of the line with its $H^1$-type geometry.\par The equation is similar to KdV but different in many details, as is its mode of solution. There is an associated acoustic'' spectral problem $$y''+\textstyle{{1\over 4}} y=\lambda my\tag 2$$ in which $m= v- v''$, and it is natural to attempt the linearization of (1) on the Jacobi variety of the (hyperelliptic) Riemann surface associated with the Floquet multipliers of (2). This does not work well, but a double cover of that Riemann surface does the trick. That is one novelty compared to the case of KdV. Another is the appearance on the Riemann surface of some number of nodes where KdV would have ordinary ramifications. These correspond to the possibility of soliton-anti-soliton collisions'' and have to be treated in a novel way.
[H.P.McKean (New York) and A.Constantin (Zürich)]
MSC 2000:
*35Q53 KdV-like equations
37K20 Relations with algebraic geometry, etc.
76B15 Wave motions (fluid mechanics)

Keywords: projective curves; KdV-like equations; water waves; solition-anti-soliton collisions; periodic case of the shallow water equation; Jacobi variety; Riemann surface

Citations: Zbl 0808.76011

Highlights
Master Server