论文标题
半线性抛物线系统具有时空强迫术语的爆炸和全球存在
Blow-up and global existence for semilinear parabolic systems with space-time forcing terms
论文作者
论文摘要
我们研究了对不均匀抛物线系统的局部存在,有限的时间爆炸和全球存在,其签名解决方案具有时空强迫术语$ _t-u_t-ΔU= | v | v |^{p}+t^σw_1(x),\,\,\,\,\,v_t-t-ΔV= | (u(0,x),v(0,x))=(u_0(x),v_0(x)),$$其中$ t> 0 $,$ x \ in \ mathbb {r}^n $,$ n \ geq 1 $,$ p,$ p,q> 1 $,$ q> 1 $,$σ,$σ $ w_1,w_2 \ not \ equiv0 $,$ u_0,v_0 \ in C_0(\ Mathbb {r}^n)$。对于有限的时间爆炸,在l^1(\ Mathbb {r}^n)$和$ \ int _ {\ Mathbb {r}^n} w_i(x)\,dx> 0 $,$ i = 1,2 $的条件下讨论了两种情况。也就是说,如果$σ> 0 $或$γ> 0 $,我们表明(温和的)解决方案$(u,v)$在有限的时间内爆炸,而如果$σ,γ\ in(-1,1,0)$,则在$ \ frac {n} {2} {2} {2} {2} {2} {2} {2} <n}时发生有限的时间爆炸\ max \ left \ {\ frac {(σ+1)(pq-1)+p+1} {pq-1},\ frac {(γ+1)(pq-1)(pq-1)+q+1} {pq-1} {pq-1} {pq-1} \ right \} $。此外,如果$ \ \ \ frac {n} {2} \ geq \ max \ left \ left \ {\ frac {(σ+1)(PQ-1)(pq-1)+p+1} {pq-1} {pq-1},\ frac {(γ+1)(pq-1)+q+1} $ q> \fracγσ$,我们证明该解决方案是适合初始值的全局,$ w_i $,$ i = 1,2 $。
We investigate the local existence, finite time blow-up and global existence of sign-changing solutions to the inhomogeneous parabolic system with space-time forcing terms $$ u_t-Δu =|v|^{p}+t^σw_1(x),\,\, v_t-Δv =|u|^{q}+t^γw_2(x),\,\, (u(0,x),v(0,x))=(u_0(x),v_0(x)), $$ where $t>0$, $x\in \mathbb{R}^N$, $N\geq 1$, $p,q>1$, $σ,γ>-1$, $σ,γ\neq0$, $w_1,w_2\not\equiv0$, and $u_0,v_0\in C_0(\mathbb{R}^N)$. For the finite time blow-up, two cases are discussed under the conditions $w_i\in L^1(\mathbb{R}^N)$ and $\int_{\mathbb{R}^N} w_i(x)\,dx>0$, $i=1,2$. Namely, if $σ>0$ or $γ>0$, we show that the (mild) solution $(u,v)$ to the considered system blows up in finite time, while if $σ,γ\in(-1,0)$, then a finite time blow-up occurs when $\frac{N}{2}< \max\left\{\frac{(σ+1)(pq-1)+p+1}{pq-1},\frac{(γ+1)(pq-1)+q+1}{pq-1}\right\}$. Moreover, if $\frac{N}{2}\geq \max\left\{\frac{(σ+1)(pq-1)+p+1}{pq-1},\frac{(γ+1)(pq-1)+q+1}{pq-1}\right\}$, $p>\fracσγ$ and $q>\fracγσ$, we show that the solution is global for suitable initial values and $w_i$, $i=1,2$.