25 research outputs found

    New Charged Dilaton Solutions in 2+1 Dimensions and Solutions with Cylindrical Symmetry in 3+1 Dimensions

    Full text link
    We report a new family of solutions to Einstein-Maxwell-dilaton gravity in 2+1 dimensions and Einstein-Maxwell gravity with cylindrical symmetry in 3+1 dimensions. A set of static charged solutions in 2+1 dimensions are obtained by a compactification of charged solutions in 3+1 dimensions with cylindrical symmetry. These solutions contain naked singularities for certain values of the parameters considered. New rotating charged solutions in 2+1 dimensions and 3+1 dimensions are generated treating the static charged solutions as seed metrics and performing SL(2;R)SL(2;R) transformations.Comment: Latex. No figure

    A unified Witten-Reshetikhin-Turaev invariant for integral homology spheres

    Full text link
    We construct an invariant J_M of integral homology spheres M with values in a completion \hat{Z[q]} of the polynomial ring Z[q] such that the evaluation at each root of unity \zeta gives the the SU(2) Witten-Reshetikhin-Turaev invariant \tau_\zeta(M) of M at \zeta. Thus J_M unifies all the SU(2) Witten-Reshetikhin-Turaev invariants of M. As a consequence, \tau_\zeta(M) is an algebraic integer. Moreover, it follows that \tau_\zeta(M) as a function on \zeta behaves like an ``analytic function'' defined on the set of roots of unity. That is, the \tau_\zeta(M) for all roots of unity are determined by a "Taylor expansion" at any root of unity, and also by the values at infinitely many roots of unity of prime power orders. In particular, \tau_\zeta(M) for all roots of unity are determined by the Ohtsuki series, which can be regarded as the Taylor expansion at q=1.Comment: 66 pages, 8 figure

    Quotients of AdS_{p+1} x S^q: causally well-behaved spaces and black holes

    Full text link
    Starting from the recent classification of quotients of Freund--Rubin backgrounds in string theory of the type AdS_{p+1} x S^q by one-parameter subgroups of isometries, we investigate the physical interpretation of the associated quotients by discrete cyclic subgroups. We establish which quotients have well-behaved causal structures, and of those containing closed timelike curves, which have interpretations as black holes. We explain the relation to previous investigations of quotients of asymptotically flat spacetimes and plane waves, of black holes in AdS and of Godel-type universes.Comment: 48 pages; v2: minor typos correcte

    Plane-symmetric inhomogeneous magnetized viscous fluid universe with a variable Λ\Lambda

    Full text link
    The behavior of magnetic field in plane symmetric inhomogeneous cosmological models for bulk viscous distribution is investigated. The coefficient of bulk viscosity is assumed to be a power function of mass density (Ο=Ο0ρn)(\xi =\xi_{0}\rho^{n}). The values of cosmological constant for these models are found to be small and positive which are supported by the results from recent supernovae Ia observations. Some physical and geometric aspects of the models are also discussed.Comment: 18 pages, LaTex, no figur

    Impact of CP phases on the search for sleptons tau and nu_tau

    Get PDF
    We study the decays of the tau-sleptons (stau_{1,2}) and tau-sneutrino (snu_tau) in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters A_tau, mu and M_1 (U(1) gaugino mass). We show that the effect of the CP phases of these parameters on the branching ratios of stau_{1,2} and snu_tau decays can be quite strong in a large region of the MSSM parameter space. This could have an important impact on the search for stau_{1,2} and snu_tau and the determination of the MSSM parameters at future colliders.Comment: 15 pages, 5 figures, LaTeX2

    Global Boundary Stratotype Section and Point (GSSP) for the Anthropocene Series: Where and how to look for potential candidates

    Get PDF
    International audienc

    Fabrication of a microfluidic chip for PCR applications

    No full text
    The fabrication of a microfluidic chip for application to polymerase chain (PCR) is presented. In this chip, a micro peristaltic pump was integrated to pump a reactant droplet. PCR reaction chambers, Pt heaters, temperature sensors, and pn-diodes were fabricated on a silicon wafer. Access holes for fluid and electrical connections, and pump membranes were etched in a Pyrex wafer, which was anodically bonded onto the silicon. Three PZT discs were glued on pump membranes to actuate the micro peristaltic pump
    corecore