Speaker
Description
Pseudo entropy is a complex-valued generalization of entanglement entropy defined from a transition matrix between two quantum states. In this talk, I will discuss the physical meaning of its imaginary part for real-time quantum evolution. I will first show that its short-time response is governed by a correlation between the physical Hamiltonian and the modular Hamiltonian of a subsystem. In particular, the imaginary part is controlled by a symmetrized modular covariance, which provides a microscopic measure of temporal orientation. I will then explain how this quantity acquires an operational meaning through a calibrated replica interferometer: the pseudo-Rényi phase, together with the interference visibility, determines the optimal distinguishability between opposite transition orientations. Finally, I will discuss many-body examples, coarse graining, and the relation between temporal orientation and irreversibility.