摘要

We study the Cauchy problem of the Ostrovsky equation partial derivative(t)u - beta partial derivative(3)(x)u - gamma partial derivative(-1)(x)u u partial derivative(x)u = 0, with beta gamma < 0. By establishing a bilinear estimate on the anisotropic Bourgain space X-s.w.b, we prove that the Cauchy problem of this equation is locally well-posed in the anisotropic Sobolev space H-(s,H-w)(R) for any s > -5/8 and some omega is an element of (0, 1/2). Using this result and conservation laws of this equation, we also prove that the Cauchy problem of this equation is globally well-posed in H-(s,H-w)(R) for s > 0.