2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/83990The time-dependent electromagnetic field can results both pair waves and pair particles. It can be for mathematical relations between two functions with identical argument and difference of phases equal to $π$. Two examples both the opportunity of phase synchronism for different frequencies of at atom-field interaction with known abnormal dispersion of refraction and the possible trajectories for pair particles are considered.20 pagesAtomic Physicstext