Evaporation of Three Dimensional Black Hole in Quantum Gravity

We discuss an evaporation of (2+1)-dimensional black hole by using quantum gravity holding in the vicinity of the black hole horizon. It is shown that the black hole evaporates at a definite rate by emitting matters through the quantum tunneling effect. A relation of the present formalism to the black hole entropy is briefly commented.Comment: 13 pages, phyzz

The Pacific herring, Clupea harengus pallasi, open pound roe-on-kelp experimental fishery in San Francisco Bay, 1988 to 1989

The experimental open pound herring roe-on-kelp (ROK) fishery was studied in San Francisco Bay from the second week of December 1988 through the third week of February 1989. Three spawning runs were fished successfully by four operations consisting of six permittees. A total of 47.1 tons of herring ROK was packed this season. Giant kelp, Macrocystis sp., was harvested from the Santa Barbara Channel Islands and trucked to San Francisco for hanging on the pounds. Sources of high-quality giant kelp in California were difficult to locate this season because of unfavorable oceanographic conditions during the winter months. ROK was sampled at each shoreside processing facility. There were no significant differences in ROK blade measurements or roe densities among the permittees. ROK densities ranged from 0.250 to 0.699 g/cm2. Plastic totes containing processed ROK averaged 1756 lbs total gross weight. Totes contained an average of 42.3% ROK by weight. Siltation of ROK harvested in south San Francisco Bay continued to be a problem. High winds damaged rafts in December 1988. Gear conflicts were reported between ROK and herring roe permittees. (25pp.

Topological Symmetry, Background Independence, and Matrix Models

We illustrate a physical situation in which topological symmetry, its breakdown, space-time uncertainty principle, and background independence may play an important role in constructing and understanding matrix models. First, we show that the space-time uncertainty principle of string may be understood as a manifestation of the breakdown of the topological symmetry in the large $N$ matrix model. Next, we construct a new type of matrix models which is a matrix model analog of the topological Chern-Simons and BF theories. It is of interest that these topological matrix models are not only completely independent of the background metric but also have nontrivial "p-brane" solutions as well as commuting classical space-time as the classical solutions. In this paper, we would like to point out some elementary and unsolved problems associated to the matrix models, whose resolution would lead to the more satisfying matrix model in future.Comment: 19 pages, LaTex, Invited paper to appear in the special issue of the Journal of Chaos, Solitons and Fractals on "Superstrings, M, F, S, ....... Theory", edited by M.S. El Naschie and C. Castr

Pacific herring, Clupea harengus pallasi, studies in San Francisco and Tomales Bays, April 1989 to March 1990

Herring schools were surveyed hydroacoustically in San Francisco Bay from early November 1989 through mid March 1990. Seven large schools (>1000 tons) and two smaller ones were detected. The total acoustic biomass estimate based on visual integration was 58,100 tons. Merging with the independent spawn escapement estimate yielded a "best" estimate of 64,500 tons. Sixty-three samples, containing 10,239 herring, were collected. Patterns evident in prior seasons continue. Larger, older fish continue to dominate early season schools. Males continue to be numerically superior during the first half of the season. Mean size and weight at age suggest conditions following the 1988-89 season were not favorable for growth. Contrary to forecasts, the 1988 year class recruitment strength was high; second only to the 1982 year class. Although still being validated, forecasts suggest the 1989 year class will be strong and the 1990 year class will be extremely weak. (64pp.

Introducing Dynamical Triangulations to the Type IIB Superstrings

In order to consider non-perturbative effects of superstrings, we try to apply dynamical triangulations to the type IIB superstrings. The discretized action is constructed from the type IIB matrix model proposed as a constructive definition of superstring theory. The action has the local N=2 supersymmetry explicitly, and has no extra fermionic degrees of freedom. We evaluate the partition function for some simple configurations and discuss constraints required from the finiteness of partition functions.Comment: LATTICE99, 3 pages, LaTeX with 2 figures, espcrc2.st

Grand-canonical simulation of two-dimensional simplicial gravity

The string susceptibility exponents of dynamically triangulated 2-dimensional surfaces with various topologies, such as a sphere, torus and double-torus, were calculated by the grand-canonical Monte Carlo method. These simulations were made for surfaces coupled to $d$-Ising spins ($d$=0,1,2,3,5). In each simulation the area of surface was constrained to within 1000 to 3000 of triangles, while maintaining the detailed-balance condition. The numerical results show excellent agreement with theoretical predictions as long as $d \leq 2$.Comment: 9 pages, Latex include 5 postscript figures, using psfig.sty and cite.st

Pacific Herring, Clupea pallasi, spawning population assessment for San Francisco Bay, 1992-93

We conducted hydroacoustic surveys, spawn surveys, and sampled schools and fishery landings from 8 November 1992 through 18 March 1993 to assess the status of San Francisco Bay's Pacific herring spawning population. Our spawning biomass estimate of 21,186 tons is the lowest since 1978 when subtidal spawns were included in estimates; it also represents a third consecutive season of decline. The principal reason for this very low estimate is a lack of two-, three-, and four-year-old herring in the spawning population from the 1991,1990, and 1989 year-classes. Although four-year-olds were the most abundant cohort, their actual number was very low. Five-year-olds from the highly successful 1988 year-class were the second most abundant cohort. Warm-water conditions and poor upwelling associated with the 1991-92 El Nino are likely causes of the low spawning biomass, although adverse impacts on the condition and growth of spawners were not apparent. Warm water may have displaced herring to the north of San Francisco Bay. We also continued to collect data for a herring young-of-the-year abundance index during April, May, and June of 1993. The index was low for the 1990 and 1991 year-classes, but high for the 1989 year-class. The 1989 and 1990 year-classes appear poor; however, the success of the 1991 year-class will not be known until next season when it fully recruits to the spawning population.The index for the 1992 year-class is relatively low as is the index for 1993. The season's 5,555-ton quota (based on the previous season's biomass estimate) exceeded our harvest goal of no more than 20% of spawning biomass for the first time since the 1970s. The number of three-year-old fish in gill net catches increased substantially this season, possibly indicating the use of smaller mesh. Because of the extremely low spawning biomass and uncertainty about future recruitment, our recommendation to the Fish and Game Commission was to close the herring roe fishery in San Francisco Bay until the season following a spawning biomass estimate of 26,000 tons. (30pp.

Black Hole Thermodynamics from String Theory

In this note we consider a stringy description of black hole horizon. We start with a nonlinear sigma model defined on a two dimensional Euclidean surface with background Rindler metric. By solving the field equations, we show that to the leading order the Bekenstein-Hawking formula of black hole entropy can be produced. We also point out a relation between the present formalism and the 'tHooft formalism.Comment: 11, EDO-EP-

Locally Localized Gravity Models in Higher Dimensions

We explore the possibility of generalizing the locally localized gravity model in five space-time dimensions to arbitrary higher dimensions. In a space-time with negative cosmological constant, there are essentially two kinds of higher-dimensional cousins which not only take an analytic form but also are free from the naked curvature singularity in a whole bulk space-time. One cousin is a trivial extension of five-dimensional model, while the other one is in essence in higher dimensions. One interesting observation is that in the latter model, only anti-de Sitter ($AdS_p$) brane is physically meaningful whereas de Sitter ($dS_p$) and Minkowski ($M_p$) branes are dismissed. Moreover, for $AdS_p$ brane in the latter model, we study the property of localization of various bulk fields on a single brane. In particular, it is shown that the presence of the brane cosmological constant enables bulk gauge field and massless fermions to confine to the brane only by a gravitational interaction. We find a novel relation between mass of brane gauge field and the brane cosmological constant.Comment: 20 pages, LaTex 2e, revised version (to appear in Phys. Rev. D