论文标题
新型II型有限时间爆炸,用于能量超临界热方程
New type II Finite time blow-up for the energy supercritical heat equation
论文作者
论文摘要
我们考虑使用$(n-3)$ - th sobolev endent \ begin {equation*} \ begin {case} u_t =ΔU+u^{3},〜&\ mbox {in}ω\ times(times(0), \partialΩ\times (0,T),\\ u(x,0)=u_0(x),~&\mbox{ in } Ω, \end{cases} \end{equation*} where $5\leq n\leq 7$, $Ω=\R^n$ or $Ω\subset \R^n$ is a smooth, bounded domain enjoying special symmetries.我们构建II型有限时间爆破解决方案$ u(x,t)$,沿$(n-4)$ - 尺寸{\ em缩小球}以$ω$进行的奇异性。更确切地说,在领先顺序上,解决方案$ u(x,t)$属于较大的表单$$ u(x,t)\ aid \ la^{ - 1}(t)\ frac {2 \ sqrt {2}} {1+ \ left | \ frac {(r,z) - (ξ_r(t),ξ_z(t),ξ_z(t))} {\ la(t)} {\ la(t)}}} \ right |^2} $ the $ r = \ sqrt {x_1^2+\ cdots+x_ {n-3}^2} $,$ z =(x__ {n-2},x_ {n-1},x_n),x_n)$,带有$ x =(x_1,x_1,\ cdots,x_n)\ inch $。此外,奇点位置$$(ξ_r(t),ξ_z(t))\ sim(\ sqrt {2(n-4)(n-4)(t-t)},Z_0) \ frac {t-t} {| \ log(t-t-t)|^2}〜\ mbox {as} 〜t \ nearlrowt。$$这是抛物线设置中的全新现象。
We consider the energy supercritical heat equation with the $(n-3)$-th Sobolev exponent \begin{equation*} \begin{cases} u_t=Δu+u^{3},~&\mbox{ in } Ω\times (0,T),\\ u(x,t)=u|_{\partialΩ},~&\mbox{ on } \partialΩ\times (0,T),\\ u(x,0)=u_0(x),~&\mbox{ in } Ω, \end{cases} \end{equation*} where $5\leq n\leq 7$, $Ω=\R^n$ or $Ω\subset \R^n$ is a smooth, bounded domain enjoying special symmetries. We construct type II finite time blow-up solution $u(x,t)$ with the singularity taking place along an $(n-4)$-dimensional {\em shrinking sphere} in $Ω$. More precisely, at leading order, the solution $u(x,t)$ is of the sharply scaled form $$u(x,t)\approx \la^{-1}(t)\frac{2\sqrt{2}}{1+\left|\frac{(r,z)-(ξ_r(t),ξ_z(t))}{\la(t)}\right|^2}$$ where $r=\sqrt{x_1^2+\cdots+x_{n-3}^2}$, $z=(x_{n-2},x_{n-1},x_n)$ with $x=(x_1,\cdots,x_n)\inΩ$. Moreover, the singularity location $$(ξ_r(t),ξ_z(t))\sim (\sqrt{2(n-4)(T-t)},z_0)~\mbox{ as }~t\nearrow T,$$ for some fixed $z_0$, and the blow-up rate $$\la(t)\sim \frac{T-t}{|\log(T-t)|^2}~\mbox{ as }~t\nearrow T.$$ This is a completely new phenomenon in the parabolic setting.