Topological Discrete Algebra, Ground State Degeneracy, and Quark Confinement in QCD

Based on the permutation group formalism, we present a discrete symmetry algebra in QCD. The discrete algebra is hidden symmetry in QCD, which is manifest only on a space-manifold with non-trivial topology. Quark confinement in the presence of the dynamical quarks is discussed in terms of the discrete symmetry algebra. It is shown that the quark deconfinement phase has the ground state degeneracy depending on the topology of the space, which gives a gauge-invariant distinction between the confinement and deconfinement phases. We also point out that new quantum numbers relating to the fractional quantum Hall effect exist in the deconfinement phase.Comment: 11 pages, 1 figur

Near-infrared and Millimeter Constraints on the Nuclear Energy Source of the Infrared Luminous Galaxy NGC 4418

We present near-infrared and millimeter investigations of the nucleus of the infrared luminous galaxy NGC 4418, which previous observations suggest possesses a powerful buried AGN. We found the following main results: (1) The infrared K-band spectrum shows CO absorption features at 2.3-2.4 micron owing to stars and very strong H2 emission lines. The luminosity ratios of H2 emission lines are suggestive of a thermal origin, and the equivalent width of the H2 1-0 S(1) line is the second largest observed to date in an external galaxy, after the well-studied strong H2-emitting galaxy NGC 6240. (2) The infrared L-band spectrum shows a clear polycyclic aromatic hydrocarbon (PAH) emission feature at 3.3 micron, which is usually found in star-forming galaxies. The estimated star-formation luminosity from the observed PAH emission can account for only a small fraction of the infrared luminosity. (3) Millimeter interferometric observations of the nucleus reveal a high HCN (1-0) to HCO+ (1-0) luminosity ratio of 1.8, as has been previously found in pure AGNs. (4) The measurements of HCN (1-0) luminosity using a single-dish millimeter telescope show that the HCN (1-0) to infrared luminosity ratio is slightly larger than the average, but within the scattered range, for other infrared luminous galaxies. All of these results can be explained by the scenario in which, in addition to energetically-insignificant, weakly-obscured star-formation at the surface of the nucleus, a powerful X-ray emitting AGN deeply buried in dust and high density molecular gas is present.Comment: 31 pages, 9 figures, Accepted for publication in Astronomical Journal (2004 November issue

Quantum criticality of bandwidth-controlled Mott transition

Metallic states near the Mott insulator show a variety of quantum phases including various magnetic, charge ordered states and high-temperature superconductivity in various transition metal oxides and organic solids. The emergence of a variety of phases and their competitions are likely intimately associated with quantum transitions between the electron-correlation driven Mott insulator and metals characterized by its criticality, and is related to many central questions of condensed matter. The quantum criticality is, however, not well understood when the transition is controlled by the bandwidth through physical parameters such as pressure. Here, we quantitatively estimate the universality class of the transition characterized by a comprehensive set of critical exponents by using a variational Monte Carlo method implemented as an open-source innovated quantum many-body solver, with the help of established scaling laws at a typical bandwidth-controlled Mott transition. The criticality indicates a weaker charge and density instability in contrast to the filling-controlled transition realized by carrier doping, implying a weaker instability to superconductivity as well. The present comprehensive clarification opens up a number of routes for quantitative experimental studies for complete understanding of elusive quantum Mott transition and nearby strange metal that cultivate future design of functionality.Comment: 18 pages, 16 figure

Discovery of New Dwarf Galaxy near The Isolated Spiral Galaxy NGC 6503

We report the discovery of a new dwarf galaxy (NGC6503-d1) during the Subaru extended ultraviolet (XUV) disk survey. It is a likely companion of the spiral galaxy NGC6503. The resolved images, in B, V, R, i, and Halpha, show an irregular appearance due to bright stars with underlying, smooth and unresolved stellar emission. It is classified as the transition type (dIrr/dSph). Its structural properties are similar to those of the dwarfs in the Local Group, with a V absolute magnitude ~ -10.5, half-light radius ~400 pc, and central surface brightness ~25.2. Despite the low stellar surface brightness environment, one HII region was detected, though its Halpha luminosity is low, indicating an absence of any appreciable O-stars at the current epoch. The presence of multiple stellar populations is indicated by the color-magnitude diagram of ~300 bright resolved stars and the total colors of the dwarf, with the majority of its total stellar mass ~4x10^6 Msun in an old stellar population.Comment: Published in ApJL (ApJ, 802, L24). 7 pages, 4 figure

Millimeter Interferometric HCN(1-0) and HCO+(1-0) Observations of Luminous Infrared Galaxies

We present the results on millimeter interferometric observations of four luminous infrared galaxies (LIRGs), Arp 220, Mrk 231, IRAS 08572+3915, and VV 114, and one Wolf-Rayet galaxy, He 2-10, using the Nobeyama Millimeter Array (NMA). Both the HCN(1-0) and HCO+(1-0) molecular lines were observed simultaneously and their brightness-temperature ratios were derived. High-quality infrared L-band (2.8-4.1 micron) spectra were also obtained for the four LIRGs to better constrain their energy sources deeply buried in dust and molecular gas. When combined with other LIRGs we have previously observed with NMA, the final sample comprised nine LIRGs (12 LIRGs' nuclei) with available interferometric HCN(1-0) and HCO+(1-0) data-sufficient to investigate the overall trend in comparison with known AGNs and starburst galaxies. We found that LIRGs with luminous buried AGN signatures at other wavelengths tend to show high HCN(1-0)/HCO+(1-0) brightness-temperature ratios as seen in AGN-dominated galaxies, while the Wolf-Rayet galaxy He 2-10 displays a small ratio. An enhanced HCN abundance in the interstellar gas surrounding a strongly X-ray-emitting AGN, as predicted by some chemical calculations, is a natural explanation of our results.Comment: 43 pages, 11 figures, accepted for publication in Astronomical Journal. Higher resolution version is available at http://optik2.mtk.nao.ac.jp/~imanishi/Paper/HCN2/HCN2.pd

Photoinhibition of Streptococcus mutans Biofilm-Induced Lesions in Human Dentin by Violet-Blue Light

This in vitro study determined the effectiveness of violet-blue light on Streptococcus mutans (UA159) biofilm induced dentinal lesions. Biofilm was formed on human dentin specimens in a 96-well microtiter plate and incubated for 13 h in the presence of tryptic soy broth (TSB) or TSB supplemented with 1% sucrose (TSBS). Violet-blue light (405 nm) from quantitative light-induced fluorescence (QLFTM) was used to irradiate the biofilm. Supernatant liquid was removed, and the biofilm was irradiated continuously with QLF for 5 min twice daily with an interval of 6 h for 5 d, except with one treatment on the final day. Colony forming units (CFU) of the treated biofilm, changes in fluorescence (∆F; QLF-Digital BiluminatorTM), lesion depth (L), and integrated mineral loss (∆Z; both transverse microradiography) were quantified at the end of the fifth day. Statistical analysis used analysis of variance (ANOVA), testing at a 5% significance level. In the violet-blue light irradiated groups, there was a significant reduction (p < 0.05) of bacterial viability (CFU) of S. mutans with TSB and TSBS. Violet-blue light irradiation resulted in the reduction of ∆F and L of the dentinal surface with TSBS. These results indicate that violet-blue light has the capacity to reduce S. mutans cell numbers

Constraints on the perturbed mutual motion in Didymos due to impact-induced deformation of its primary after the DART impact

Binary near-Earth asteroid (65803) Didymos is the target of the proposed NASA Double Asteroid Redirection Test (DART), part of the Asteroid Impact & Deflection Assessment (AIDA) mission concept. In this mission, the DART spacecraft is planned to impact the secondary body of Didymos, perturbing mutual dynamics of the system. The primary body is currently rotating at a spin period close to the spin barrier of asteroids, and materials ejected from the secondary due to the DART impact are likely to reach the primary. These conditions may cause the primary to reshape, due to landslides, or internal deformation, changing the permanent gravity field. Here, we propose that if shape deformation of the primary occurs, the mutual orbit of the system would be perturbed due to a change in the gravity field. We use a numerical simulation technique based on the full two-body problem to investigate the shape effect on the mutual dynamics in Didymos after the DART impact. The results show that under constant volume, shape deformation induces strong perturbation in the mutual motion. We find that the deformation process always causes the orbital period of the system to become shorter. If surface layers with a thickness greater than ~0.4 m on the poles of the primary move down to the equatorial region due to the DART impact, a change in the orbital period of the system and in the spin period of the primary will be detected by ground-based measurement.Comment: 8 pages, 7 figures, 2 tables, accepted for publication in MNRA

Heisenberg realization for U_q(sln) on the flag manifold

We give the Heisenberg realization for the quantum algebra $U_q(sl_n)$, which is written by the $q$-difference operator on the flag manifold. We construct it from the action of $U_q(sl_n)$ on the $q$-symmetric algebra $A_q(Mat_n)$ by the Borel-Weil like approach. Our realization is applicable to the construction of the free field realization for the $U_q(\widehat{sl_n})$ [AOS].Comment: 10 pages, YITP/K-1016, plain TEX (some mistakes corrected and a reference added