24 citations · 45 across the 7 of their papers we have counts for
7 papers
Rayleigh-Schroedinger-Goldstone variational perturbation theory for many fermion systems
Sang Koo You, Chul Koo Kim
We present a Rayleigh-Schroedinger-Goldstone perturbation formalism for many fermion systems. Based on this formalism, variational perturbation scheme which goes beyond the Gaussia…
The Functional Schrödinger Picture Approach to Many-Particle Systems
Chul Koo Kim, Sang Koo You
A self-contained pedagogical introduction to the functional Schrödinger picture method of many-body theory is given at a level suitable for graduate students and also for many-body…
Variational perturbation approach to the Coulomb electron gas
Sang Koo You, Noboru Fukushima
The efficiency of the variational perturbation theory [Phys. Rev. C {\bf 62}, 045503 (2000)] formulated recently for many-particle systems is examined by calculating the ground sta…
A Variational Expansion for the Free Energy of a Bosonic System
Wen-Fa Lu, Sang Koo You, Jino Bak +2
In this paper, a variational perturbation scheme for nonrelativistic many-Fermion systems is generalized to a Bosonic system. By calculating the free energy of an anharmonic oscill…
A variational perturbation scheme for many-particle systems in the functional integral approach
Sang Koo You, Chul Koo Kim, Kyun Nahm +1
A variational Perturbation theory based on the functional integral approach is formulated for many-particle systems. Using the variational action obtained through Jensen-Peierls' i…
A new approximation scheme in quantum mechanics
Sang Koo You, Kwang Joe Jeon, Chul Koo Kim +1
An approximation method which combines the perturbation theory with the variational calculation is constructed for quantum mechanical problems. Using the anharmonic oscillator and…