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Spontaneous Emission of Charged Bosons from Supercritical Point Charges
Sang Pyo Kim
We study the spontaneous emission of charged bosons from supercritical Coulomb potentials and charged black holes. We find the exact emission rate from the Bogoliubov transformatio…
Particle Production from Geometric Transition in Expanding Universe
Sang Pyo Kim
The geometric transitions from the evolution in the complex plane of time provide channels for particle production for a quantum field in expanding universes. The production rate f…
Geometric Origin of Stokes Phenomenon for de Sitter Radiation
Sang Pyo Kim
We propose a geometric interpretation for the Stokes phenomenon in de Sitter spacetime that particles are produced in even dimensions but not in odd dimensions. The scattering ampl…
New Geometric Transition as Origin of Particle Production in Time-Dependent Backgrounds
Sang Pyo Kim
By extending the quantum evolution of a scalar field in time-dependent backgrounds to the complex-time plane and transporting the in-vacuum along a closed path, we argue that the g…
Landau Levels of Scalar QED in Time-Dependent Magnetic Fields
Sang Pyo Kim
The Landau levels of scalar QED undergo continuous transitions under a homogeneous, time-dependent magnetic field. We analytically formulate the Klein-Gordon equation for a charged…
Massive Scalar Field Quantum Cosmology
Sang Pyo Kim
We study the third quantized formulation of the massive inflaton quantum cosmology for the Friedmann-Robertson-Walker universe. The Hamiltonian is equivalent to an infinite number…