287 research outputs found

    Canonical treatment of two dimensional gravity as an anomalous gauge theory

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    The extended phase space method of Batalin, Fradkin and Vilkovisky is applied to formulate two dimensional gravity in a general class of gauges. A BRST formulation of the light-cone gauge is presented to reveal the relationship between the BRST symmetry and the origin of SL(2,R)SL(2,R) current algebra. From the same principle we derive the conformal gauge action suggested by David, Distler and Kawai.Comment: 11 pages, KANAZAWA-92-1

    Software.ncrna.org: web servers for analyses of RNA sequences

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    We present web servers for analysis of non-coding RNA sequences on the basis of their secondary structures. Software tools for structural multiple sequence alignments, structural pairwise sequence alignments and structural motif findings are available from the integrated web server and the individual stand-alone web servers. The servers are located at http://software.ncrna.org, along with the information for the evaluation and downloading. This website is freely available to all users and there is no login requirement

    Intermittency of Height Fluctuations and Velocity Increment of The Kardar-Parisi-Zhang and Burgers Equations with infinitesimal surface tension and Viscosity in 1+1 Dimensions

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    The Kardar-Parisi-Zhang (KPZ) equation with infinitesimal surface tension, dynamically develops sharply connected valley structures within which the height derivative is not continuous. We discuss the intermittency issue in the problem of stationary state forced KPZ equation in 1+1--dimensions. It is proved that the moments of height increments Ca=C_a = behave as x1x2ξa |x_1 -x_2|^{\xi_a} with ξa=a\xi_a = a for length scales x1x2<<σ|x_1-x_2| << \sigma. The length scale σ\sigma is the characteristic length of the forcing term. We have checked the analytical results by direct numerical simulation.Comment: 13 pages, 9 figure

    New insight into BRST anomalies in superstring theory

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    Based on the extended BRST formalism of Batalin, Fradkin and Vilkovisky, we perform a general algebraic analysis of the BRST anomalies in superstring theory of Neveu-Schwarz-Ramond. Consistency conditions on the BRST anomalies are completely solved. The genuine super-Virasoro anomaly is identified with the essentially unique solution to the consistency condition without any reference to a particular gauge for the 2D supergravity fields. In a configuration space where metric and gravitino fields are properly constructed, general form of the super-Weyl anomaly is obtained from the super-Virasoro anomaly as its descendant. We give a novel local action of super-Liouville type, which plays a role of Wess-Zumino-Witten term shifting the super-Virasoro anomaly into the super-Weyl anomaly. These results reveal a hierarchial relationship in the BRST anoamlies.Comment: 29 pages, PHYZZ

    Gauge Equivalence in Two--Dimensional Gravity

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    Two-dimensional quantum gravity is identified as a second-class system which we convert into a first-class system via the Batalin-Fradkin (BF) procedure. Using the extended phase space method, we then formulate the theory in most general class of gauges. The conformal gauge action suggested by David, Distler and Kawai is derived from a first principle. We find a local, light-cone gauge action whose Becchi-Rouet-Stora-Tyutin invariance implies Polyakov's curvature equation R=3g++=0\partial_{-}R=\partial_{-}^{3}g_{++}=0, revealing the origin of the SL(2,R)SL(2,R) Kac-Moody symmetry. The BF degree of freedom turns out be dynamically active as the Liouville mode in the conformal gauge, while in the light-cone gauge the conformal degree of freedom plays that r{\^o}le. The inclusion of the cosmological constant term in both gauges and the harmonic gauge-fixing are also considered.Comment: 30 pages, KANAZAWA 93-

    Exact Analysis of Level-Crossing Statistics for (d+1)-Dimensional Fluctuating Surfaces

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    We carry out an exact analysis of the average frequency ναxi+\nu_{\alpha x_i}^+ in the direction xix_i of positive-slope crossing of a given level α\alpha such that, h(x,t)hˉ=αh({\bf x},t)-\bar{h}=\alpha, of growing surfaces in spatial dimension dd. Here, h(x,t)h({\bf x},t) is the surface height at time tt, and hˉ\bar{h} is its mean value. We analyze the problem when the surface growth dynamics is governed by the Kardar-Parisi-Zhang (KPZ) equation without surface tension, in the time regime prior to appearance of cusp singularities (sharp valleys), as well as in the random deposition (RD) model. The total number N+N^+ of such level-crossings with positive slope in all the directions is then shown to scale with time as td/2t^{d/2} for both the KPZ equation and the RD model.Comment: 22 pages, 3 figure
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