daisyals@pusan.ac.kr

Talk title: Local Rate of the Short Hard Gamma ray Bursts and Life Time of SHB progenitors

Abstract: Recently, as the afterglow of the short hard gamma ray bursts(SHBs) were detected, the data indicated that SHB progenitor systems are different with long duration gamma ray bursts. The most promising candidates of SHB progenitors are NS-NS mergers and NS-BH mergers which are believed to be the sources of the gravitational wave that can be detected by LIGO. In this work, we calculated the local rate of SHBs to constrain their progenitor life-times with three different star formulation history models. The results show that the progenitor population has to be older than 6Gyr. We also investigated the rate with various cosmological models.

clee@pusan.ac.kr

Talk title:Spin of Stellar Mass Black Holes

Abstract: Recent estimates of the Kerr parameters a for two binaries (Shafee et al. 2006, ApJ 636, L113), GRO J1655-40 (Nova Scorpii) and 4U 1543-47 (IL Lupi), facilitate a test of stellar evolution. We found that the measured Kerr parameters are consistent with those of Lee et al. (2002, ApJ 575, 996), in which they predicted the Kerr parameters of X-ray transient sources based on the common envelope evolution which begins at the He red-giant stage of black hole progenitors. Based on this evolution, we propose a model for the evolution of GRS 1915+105, in which the spinning up the black hole by the accretion from the donor star plays an essential role to reach the observed a>0.98 (McClintock et al. 2006, ApJ 652, 518).

hyunkyu@hanyang.ac.kr

Talk title: Light curves of the radiation emitted from collapsing surfaces

Abstract: We discuss the light curves and the spectral broadening of the radiation from a collapsing surface. In a simplified model, it is possible to infer the mass enclosed inside the surface and the radius from the light curves.

hwlee@inje.ac.kr

Talk title: Developing Yee like code for numerical relativity

Abstract: We develop a roburst evolution code applying Yee's idea for general relativity.

hyunjoo@uos.ac.kr

Talk title: Quantum Wormhole and Energy Conservation

Abstract: A traversable wormhole in the semiclassical level is generalized without introducing any unnatural matter which is a source of the wormhole, and the back-reaction of the transported matter on wormhole is discussed. When a static traversable wormhole is used to transport matter, it is possible to impose a boundary condition resulting in a solution that is stable, has a continuous metric, and conserves energy.

thlee@physics.ssu.ac.kr

Talk title: Scalar-Tensor Gravity and Galactic Rotation Curves

Abstract: Considering global monopoles and cosmic strings as possible candidates for dark matter in scalar-tensor gravity theories, we study some simple models for the nearly flatness of galactic rotation curves.

jykim@kunsan.ac.kr

Talk title: Stability of internal dimension with potential in brane gas cosmology

Abstract: We consider the anisotropic evolution of spatial dimensions and the stabilization of internal dimensions in the framework of brane gas cosmology. We observe that the bulk RR field can give an effective potential which prevents the internal subvolume from collapsing. For a combination of $(D-3)$-brane gas wrapping the extra dimensions and 4-form RR flux in the unwrapped dimensions, it is possible that the wrapped subvolume has an oscillating solution around the minimum of the effective potential while the unwrapped subvolume expands monotonically. The flux gives a logarithmic bounce to the effective potential of the internal dimensions.

san2892@physics.inje.ac.kr

Talk title: Dark energy model for non-flat universe

Abstract: We obtained accelerating dark energy model using interacting matter components.

sangkim@kunsan.ac.kr

Talk title: Strong QED in Astrophysics

Abstract: Strong QED is characterized by vacuum polarization and pair production. Physics of strong QED differs from Maxwell theory by these phenomena. There can be many astrophysical processes where strong QED effects may be observable. Recently Ruffini and his group have proposed a mechanism for gamma rays bursts based on Schwinger pair production by strong electric fields but Page refuted this argument. In this talk I will critically review strong QED phenomena in astrophysics and survey many possible processes which may lead to strong electric and magnetic fields. And possible application of strong QED will be discussed.

sungwon@ewha.ac.kr

Talk title: Thermodynamics of Exotic Matter and Energy

Abstract: The exotic matters are defined as those violate the well known energy conditions and show the exotic physical properties different from normal matters. The examples of the exotic matter or exotic energy are found in squeezed state, Casimir effect, accelerating Universe, etc. In this paper the thermodynamic properties of exotic matter and energy are examined. The negative entropy, negative temperature, and the violation of the second law of thermodynamics are discussed.

Talk title: Hydrodynamics and global embeddings of Taub-NUT spacetime

Abstract: TBA

xhmeng@hanyang.ac.kr

Talk title: Exact solutions of embedding a 4D Universe to a 5D Einstein manifold

Abstract: A five dimensional Einstein equation with its right hand side empty, one of the simplest extended gravity models by one more spacial dimension, induces a four-dimensional cosmological model accordingly, which suggests that the matter in the Universe originates from the one extra dimension [P.S. Wesson, Space-Time-Matter]. We consider the case that a cosmological constant $\Lambda$ exists in the 5D Universe and obtain exact solutions for $\Lambda>0$ and $\Lambda<0$. In the 5D Universe with cosmological constant, not only can it be naturally reduced to the power-law $\Lambda$CDM model for the 4D real Universe, but also the arbitrary functions and constants in the metric are endowed with explicit physical meanings.