Kee Yong Kim

Batalin-Tyutin quantization of the self-dual massive theory in three dimensions

We quantize the self-dual massive theory by using the Batalin-Tyutin Hamiltonian method, which systematically embeds a second class constraint system into a first class one in extended phase space by introducing new fields. Through this analysis we obtain simultaneously the Stueckelberg scalar term related to the explicit gauge-breaking effect and a new type of Wess-Zumino action related to the Chern-Simons term.

COSMOLOGICAL EVOLUTION OF NEW-AGEGRAPHIC DARK ENERGY MODEL

We investigate the cosmological evolution of the new-agegraphic dark energy model which was recently proposed to explain the dark energy-dominated universe. For this purpose, we derived differential equations for density parameters and solved them numerically. We found that there exist a critical value for undetermined parameter of new-agegraphic density to obtain a stable and accessible evolution in the far past. Furthermore, this parameter seems to be fixed as the critical value for consistence.

PHYSICAL SPECTRUM OF CHIRAL SCHWINGER MODEL IN THE MATTER GAUGE

We study the physical spectrum and the fermionic operator solutions of the chiral Schwinger model and the minimal chiral Schwinger model in the matter gauge.

EVIDENCE FOR SO(6) ⊗ SO(6) STRUCTURE IN NUCLEI

We study odd-A nuclei by imposing SO(6) ⊗ SO(6) symmetry. Spinor representations constitute bases for bosonic states in contrast to interacting boson-fermion model. Low-lying energy spectra of gold isotopes are analyzed in this model. The agreement between calculated and experimental level spectra is found to be satisfactory.

SU(m/n) weight systems and superprojection matrices

Representations of the SU(m/n) superalgebra are studied in terms of the Kac–Dynkin weight systems. Superprojection matrices are introduced for the possible branching patterns.

LORENTZ INVARIANT SPECTRUM OF MINIMAL CHIRAL SCHWINGER MODEL

We study the Lorentz transformation of the minimal chiral Schwinger model in terms of the alternative action. We automatically obtain a chiral constraint, which is equivalent to the frame constraint introduced by McCabe, in order to solve the frame problem in phase space. As a result we obtain the Lorentz invariant spectrum in any moving frame by choosing a frame parameter.

REALIZATION OF THE FADDEEVIAN REGULARIZATION IN AN ANOMALOUS GAUGE THEORY

We analyze the minimal chiral Schwinger model with the Wess-Zumino action in the Hamiltonian formulation and show that Mitra’s “Faddeevian regularization” originates in the matter gauge-fixed model in the case of a regularization ambiguity with a=2. Furthermore, we obtain the generalized model which satisfies the Faddeevian regularization for a≥1.

Equivalence of light-cone and conformal gauges in two-dimensional quantum gravity

We show that the light-cone and conformal gauges are equivalent in the sense that the well known SL(2, ℝ) current structure in the light-cone gauge is obtained from the results in the conformal one under a proper coordinate transformation. This result is due to the residual symmetry of the scalar field Φ.

BRS analysis of the energy momentum tensor in two-dimensional gravity

Majorana fermion coupled to a 2-dimensional background gravitational field is investigated by employing the BRS quantization technique. Upon introduction of a quasicon-formal map ζ determined by the Beltrami differential h, the background gravitational field amazingly disappeared leaving just the free Majorana field ψ and ghosts b, c. In this way the vacuum expectation value of the energy-momentum tensor under the background gravitational field is explicitly computed.

Eight-dimensional, N=1 supergravity with SU(4/1) hidden supersymmetry.

We describe {ital D}=8, {ital N}=1 supergravity with an SU(4/1) superalgebra which is a supersymmetric version of SO(6){direct product}U(1). Possible supermultiplets agree with typical representations of SU(4/1). Furthermore U(1) supercharges are automatically determined by just demanding that the representation is real. Dimensional reductions to the {ital D}=7,{ital N}=2 and {ital D}=6,{ital N}=2 theories are described by using branching rules of SU(4/1).