KdV and Almost Conservation Laws
نویسنده
چکیده
In this article we illustrate a new method to extend local wellposedness results for dispersive equations to global ones. The main ingredient of this method is the definition of a family of what we call almost conservation laws. In particular we analyze the Korteweg-de Vries initial value problem and we illustrate in general terms how the “algorithm” that we use to formally generate almost conservation laws can be used to recover the infinitely many conserved integrals that make the KdV an integrable system.
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