Abstract

Abstract The recent past quantum state formalism [Phys. Rev. Lett. \textbf{111}, 160401 (2013)] indicates that the outcome
probability of the measurement performed on a quantum system at time $t$
shows dependence on the measurement events recorded until that time, and is
also revised by the outcomes acquired after time $t$. We apply the past
quantum state formalism to calculate the three-time correlation
function of a radiation field and to analyze the conditional dynamics on the
pre- and postselection by the first and last detection events. The persistent oscillations in the three-time field correlation function, which cannot be well understood by the usual quantum regression theorem, are straightforwardly explained by the probabilistic
knowledge of the past and the future through the past quantum state
reasoning.