2 problems

Let $u_0\in L^2$ be initial data for the one-dimensional quintic nonlinear Schrödinger equation, and consider a solution $u$ that develops mass concentration near a blow-up time…

Let $K(x)=|x|^\alpha$ with $0<\alpha<2$, and let the initial data belong to $L_p$ for $p<p_s$. In the special case $\alpha=1$, instantaneous mass concentration has been established…