Comment on ’’Use of the time evolution operator’’

Onno L. J. Gijzeman, Kalbe Razi Naqvi

Mostafazadeh, Ali

I point out that if one defines the operator $U_R(t)$ as done by M. Znojil in his reply [arXiv:0711.0514v1] to my comment [arXiv:0711.0137v1] and also accepts the validity of the defining relation of $U_R(t)$ as given in his paper [arXiv:0710.5653v1], one finds that the time-evolution of the associated quantum system is not governed by the Schrödinger equation for the Hamiltonian operator $H$ but an operator $H'$ which differs from $H$ if the metric operator is time-dependent. In the latter case this effective Hamiltonian $H'$ is not observable. This is consistent with the conclusions of my paper [Phys. Lett. B 650, 208 (2007), arXiv:0706.1872v2] which allow for unitary time-evolution generated by unobservable Hamiltonians.

Adam Fredriksson, Erik Sjöqvist

We show that the claim in Ref. [PRL 131, 200202 (2023)], that the quantum time evolution always can be written as a product of a holonomy operator and a dynamic operator, is false, as it is based on a circular use of the time evolution operator.

Gebhard Grübl, C. Leubner

Haider R. Zaidi, Fan Hong-Yi

We disagree with the conclusions of the preceding Comment [Janszky and Yushin, Phys. Rev. A 39, 5437 (1989)]. It is shown in this Reply that a squeeze operator can also serve as the time evolution operator for a Franck-Condon transition, and that our previous interpretation is correct. It is also pointed out that the model Hamiltonian used in the preceding Comment is not appropriate for a Franck-Condon transition.

Per‐Olov Löwdin, P. K. Mukherjee