arXiv subjects

S. P. Kim

Publications and source records attributed to S. P. Kim.

3 recordsLinked to original sources

arXiv2000

Generalized Invariants and Quantum Evolution of Open Fermionic System

Open systems acquire time-dependent coupling constants through interaction with an external field or environment. We generalize the Lewis-Riesenfeld invariant theorem to open system of quantum fields after second quantization. The generalized invariants and thereby the quantum evolution are found explicitly for time-dependent quadratic fermionic systems. The pair production of fermions is computed and other physical implications are discussed.

hep-th↗

arXiv1999

The traversable wormhole with classical scalar fields

We study the Lorentzian static traversable wormholes coupled to quadratic scalar fields. We also obtain the solutions of the scalar fields and matters in the wormhole background and find that the minimal size of the wormhole should be quantized under the appropriate boundary conditions for the positive non-minimal massive scalar field.

gr-qc↗

arXiv1997

Heisenberg-picture approach to the evolution of the scalar fields in an expanding universe

We present the Heisenberg-picture approach to the quantum evolution of the scalar fields in an expanding FRW universe which incorporates relatively simply the initial quantum conditions such as the vacuum state, the thermal equilibrium state, and the coherent state. We calculate the Wightman function, two-point function, and correlation function of a massive scalar field. We find the quantum evolution of fluctuations of a self-interacting field perturbatively and discuss the renormalization of field equations.

gr-qc↗