How would MWI explain the delayed choice quantum eraser? http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser#The_experiment_of_Kim_et_al._.282000.29 I don't see how this can be explained with MWI. If the idler photon hits detector 1 or 2, an interference pattern can be seen on the screen. If the idler photon hits detector 3 or 4, NO interference pattern is seen. But the screen is hit BEFORE the idler photon hits the detector. Can someone please explain this in detail according to the MWI explanation?