2008/10/31 by Zihua Guo · 1 citation
Mathematics · #math.AP #msc:35Q53
published as J. Math. Pures Appl. 91 (2009) 583-597 · 20 pages, 0 figure
arxiv created 2009/04/20 · arxiv updated 2010/07/27
We prove that the Korteweg-de Vries initial-value problem is globally well-posed in H-3/4(\R) and the modified Korteweg-de Vries initial-value problem is globally well-posed in H1/4(\R). The new ingredient is that we use directly the contraction principle to prove local well-posedness for KdV equation at s=-3/4 by constructing some special resolution spaces in order to avoid some 'logarithmic divergence' from the high-high interactions. Our local solution has almost the same properties as those for Hs (s>-3/4) solution which enable us to apply the I-method to extend it to a global solution.