Ill-posedness for One-dimensional Wave Maps at the Critical Regularity
نویسنده
چکیده
We show that the wave map equation in R is in general illposed in the critical space Ḣ1/2, and the Besov space Ḃ 1/2,1 2 . The problem is attributed to the bad behaviour of the one-dimensional bilinear expression D(fDg) in these spaces.
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