Speaker
Description
We investigate the quantum-to-classical transition of primordial perturbations
within a two-field inflationary framework where an adiabatic mode interacts with an entropic environment. In the case of a massive entropic environment, the attractor Bunch–Davies vacuum plays a special role: it is the only state that can undergo full recoherence, whereas all excited initial states exhibit persistent loss of purity. To characterize this behavior, we parameterize excited Gaussian initial states by their Bogoliubov coefficients and compute the purity and Rényi-2 entropy of the reduced adiabatic state as information-theoretic indicators of decoherence dynamics. We find that excited states display purity-freezing at a non-zero plateau, where residual quantum correlations persist indefinitely, a qualitative departure from the complete recoherence observed for the Bunch–Davies vacuum. This sensitivity to initial conditions highlights the non-generic nature of full recoherence in the quantum-to-classical transition of inflationary perturbations.