“…the admissible dynamics are the ones corresponding to the subdomain Ω L ε,ε and entering Ω L ε,ε , or corresponding to the subdomain Ω R ε,ε and entering Ω R ε,ε . Hence the situation differs from those studied in the articles of G. Barles, A. Briani and E. Chasseigne [8,9] and of G. Barles, A. Briani, E. Chasseigne and N. Tchou [11], in which mixing is allowed at the interface. The optimal control problem under consideration has been first studied in [25]: the value function is characterized as the viscosity solution of a Hamilton-Jacobi equation with special transmission conditions on Γ ε,ε ; a comparison principle for this problem is proved in [25] with arguments from the theory of optimal control similar to those introduced in [8,9].…”