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Time-dependent Displaced and Squeezed Number States
Sang Pyo Kim
We generalize the wave functions of the displaced and squeezed number states, found by Nieto, to a time-dependent harmonic oscillator with variable mass and frequency. These time-d…
Squeezed States of the Generalized Minimum Uncertainty State for the Caldirola-Kanai Hamiltonian
Sang Pyo Kim
We show that the ground state of the well-known pseudo-stationary states for the Caldirola-Kanai Hamiltonian is a generalized minimum uncertainty state, which has the minimum allow…
Thermofield Dynamics of Time-Dependent Boson and Fermion Systems
Sang Pyo Kim, F. C. Khanna
We formulate the thermofield dynamics for time-dependent systems by combining the Liouville-von Neumann equation, its invariant operators, and the basic notions of thermofield dyna…
Invariant Operators vs Heisenberg Operators for Time-Dependent Generalized Oscillators
Sang Pyo Kim
We investigate the relation between the invariant operators satisfying the quantum Liouville-von Neumann and the Heisenberg operators satisfying the Heisenberg equation. For time-d…
Schwinger Pair Production in Electric and Magnetic Fields
Sang Pyo Kim, Don N. Page
Charged particles in static electric and magnetic fields have Landau levels and tunneling states from the vacuum. Using the instanton method of Phys. Rev. D 65, 105002 (2002), we o…
Nonequilibrium Evolution of Correlation Functions: A Canonical Approach
Supratim Sengupta, F. C. Khanna, Sang Pyo Kim
We study nonequilibrium evolution in a self-interacting quantum field theory invariant under space translation only by using a canonical approach based on the recently developed Li…