Multi-travelling waves for the nonlinear klein-gordon equation
  For the nonlinear Klein-Gordon equation in R 1+d , we prove the existence of multi-solitary waves made of any number N of decoupled bound states. This extends the work of C{\^o}te and Mu{\~n}oz (Forum Math. Sigma 2 (2014)) which was restricted to ground states, as were most previous similar results for other nonlinear dispersive and wave models. 
Rapha\"el C\^ote (IRMA), Yvan Martel (CMLS)
math.AP