k-ended $O(m) times O(n)$ invariant solutions to the Allen-Cahn equation with infinite Morse index

Abstract: In this work we study existence, asymptotic behaviour and stability properties of $O(m) times O(n)$ invariant solutions of the Allen-Cahn equation $Delta u+u(1-u^2)=0$ in $R^m times R^n$ with $m,n ge 2$, $m+n ge 8$. We exhibit four families of solutions whose nodal sets are smooth logarithmic corrections of the Lawson cone and with infinite Morse index. This work complements the study started by Pacard and Wei (about stable solutions) and by Agudelo, Kowalczyk and Rizzi (about 2 ended solutions).