Phase-space structure for two- and three-sine-wave initial conditions shortly after collapse. This figure is analogous to Fig. 2, except that we compare predictions of LPT at various orders in the ballistic approximation framework with measurements in Vlasov simulations shortly after collapse, i.e. for a = a_sc + Δa, as listed in Table 1 and discussed in the main text. We note that the additional cyan curve corresponds to the LPT prediction at the tenth order without using the ballistic approximation.