122 citations
6 papers · 1 filter
Strong Scalar QED in Inhomogeneous Electromagnetic Fields
Sang Pyo Kim
Strong QED has attracted attention recently partly because many astrophysical phenomena have been observed to involve electromagnetic fields beyond the critical strength for electr…
Schwinger Pair Production at Finite Temperature in Scalar QED
Sang Pyo Kim, Hyun Kyu Lee
In scalar QED we study the Schwinger pair production from an initial ensemble of charged bosons when an electric field is turned on for a finite period together with or without a c…
Ricci Flat Black Holes and Hawking-Page Phase Transition in Gauss-Bonnet Gravity and Dilaton Gravity
Rong-Gen Cai, Sang Pyo Kim, Bin Wang
It is well-known that there exists a Hawking-Page phase transition between a spherical AdS black hole and a thermal AdS space. The phase transition does not happen between a Ricci…
Ellipsoidal universe in the brane world
Xian-Hui Ge, Sang Pyo Kim
We study a scenario of the ellipsoidal universe in the brane world cosmology with a cosmological constant in the bulk . From the five-dimensional Einstein equations we derive the e…
Improved Approximations for Fermion Pair Production in Inhomogeneous Electric Fields
Sang Pyo Kim, Don N. Page
Reformulating the instantons in a complex plane for tunneling or transmitting states, we calculate the pair-production rate of charged fermions in a spatially localized electric fi…
New variational perturbation theory based on deformed oscillator
Hyeong-Chan Kim, Jae Hyung Yee, Sang Pyo Kim
A new variational perturbation theory is developed based on the deformed oscillator. It is shown that the new variational perturbation method provides 200 or 10 times better ac…