A Landesman-Lazer type result for periodic parabolic problems on ${\mathbb{R}}^N$ at resonance

Aleksander Cwiszewski, Renata Lukasiak

We are concerned with $T$-periodic solutions of nonautonomous parabolic problem of the form $u_t=\Delta u+V(x)u+f(t,x,u)$, $t>0$, $x\in {\mathbb{R}}^N$, with $V \in L^\infty (\mat…