2016/07/10 by Majdoub, Mohamed, Tayachi, Slim
#Analysis of PDEs (math.AP) #FOS: Mathematics
paper · doi:10.48550/arxiv.1607.02723
In this paper we consider the problem: ∂t u- Δu=f(u), u(0)=u0∈ exp Lp(\RN), where p>1 and f : \R→\R having an exponential growth at infinity with f(0)=0. We prove local well-posedness in exp Lp0(\RN) for f(u)∼ e|u|q, 00, \liminfs→ ∞(f(s) \rme-λsp)>0, then non-existence occurs in exp Lp(\RN). Under smallness condition on the initial data and for exponential nonlinearity f such that |f(u)|∼ |u|m as u→ 0, N(m-1)\over 2≥ p, we show that the solution is global. In particular, p-1>0 sufficiently small is allowed. Moreover, we obtain decay estimates in Lebesgue spaces for large time which depend on m.