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May 2005 arXiv papers — page 11

Showing 1,001–1,100 of 3,731 papers

  1. Seiji Terashima

    We study the fuzzy or noncommutative Dp-branes in terms of infinitely many unstable D0-branes, from which we can construct any Dp-branes. We show that the tachyon condensation of the unstable D0-branes induces the noncommutativity. In the infinite tachyon condensation limit, most of the unstable D0-branes disappear and remaining D0-branes are actually the BP

  2. Jerome P. Gauntlett, Sangmin Lee, Toni Mateos, Daniel Waldram

    We generate new AdS_4 solutions of D=11 supergravity starting from AdS_4 x X_7 solutions where X_7 has U(1)^3 isometry. We consider examples where X_7 is weak G_2, Sasaki-Einstein or tri-Sasakian, corresponding to d=3 SCFTs with N=1,2 or 3 supersymmetry, respectively, and where the deformed solutions preserve N=1,2 or 1 supersymmetry, respectively. For the s

  3. Sergio Benvenuti, Martin Kruczenski

    The AdS/CFT correspondence between Sasaki-Einstein spaces and quiver gauge theories is studied from the perspective of massless BPS geodesics. The recently constructed toric Lpqr geometries are considered: we determine the dual superconformal quivers and the spectrum of BPS mesons. The conformal anomaly is compared with the volumes of the manifolds. The U(1)

  4. Dmitri Diakonov, Victor Petrov

    In the Relativistic Mean Field Approximation three quarks in baryons from the lowest octet and the decuplet are bound by the self-consistent chiral field, and there are additional quark-antiquark pairs whose wave function also follows from the mean field. We present a generating functional for the 3-quark, 5-quark, 7-quark ... wave functions inside the octet

  5. K. S. Babu, Cosmin Macesanu

    We consider a minimal formulation of SO(10) Grand Unified Theory wherein all the fermion masses arise from Yukawa couplings involving one 126 and one 10 of Higgs multiplets. It has recently been recognized that such theories can explain, via the type-II seesaw mechanism, the large ν_μ- ν_τmixing as a consequence of b-tau unification at the GUT scale. In this

  6. M. C. Nysewander, D. E. Reichart, H. -S. Park, G. G. Williams

    We present Follow-Up Network for Gamma-Ray Bursts (FUN GRB) Collaboration observations of the optical afterglow of GRB 021211 made between 143 seconds and 102 days after the burst. Our unique data set includes the earliest filtered detections and color information for an afterglow in the pre-Swift era. We find that the afterglow is best described by (1) prop

  7. Reuven Opher, Ana Pelinson

    The Starobinsky model predicts a primordial inflation period without the presence of an inflaton field. The modified version of this model predicts a simple time dependence for the Hubble parameter $H(t)$, which decreases slowly between the Planck epoch and the end of the inflation, $H(t)=M_{\rm Pl}-βM_{\rm Pl}^2 t$, where $β$ is a dimensionless constant to

  8. Zvi Bern, Lance J. Dixon, Vladimir A. Smirnov

    We compute the leading-color (planar) three-loop four-point amplitude of N=4 supersymmetric Yang-Mills theory in 4 - 2 epsilon dimensions, as a Laurent expansion about epsilon = 0 including the finite terms. The amplitude was constructed previously via the unitarity method, in terms of two Feynman loop integrals, one of which has been evaluated already. Here

  9. Michael Dine

    Three branches of the string theory landscape have plausibly been identified. One of these branches is expected to exhibit a roughly logarithmic distribution of supersymmetry breaking scales. The original KKLT models are in this class. We argue that certain features of the KKLT model are generic to this branch, and that the resulting phenomenology depends on

  10. Alla Oleinikova, Ivan Brovchenko, Nikolai Smolin, Aliaksei Krukau

    The formation of a spanning hydrogen-bonded network of hydration water is found to occur via a 2D percolation transition in various systems: smooth hydrophilic surfaces, the surface of a single protein molecule, protein powder and diluted peptide solution. The average number of water-water hydrogen bonds nH at the percolation threshold varies from 2.0 to 2.3

  11. H. Casini, C. D. Fosco, M. Huerta

    We present some exact results about universal quantities derived from the local density matrix, for a free massive Dirac field in two dimensions. We first find the trace of powers of the density matrix in a novel fashion, which involves the correlators of suitable operators in the sine-Gordon model. These, in turn, can be written exactly in terms of the solu

  12. Alexandre Sukhov, Alexander Tumanov

    We study pseudoholomorphic discs with boundaries attached to a real hypersurface in an almost complex manifold of dimension 2. We prove that if the hypersurface contains no discs, then they fill a one sided neighborhood of the hypersurface.

  13. M. Billo, M. Caselle

    In this paper we re-derive the effective Nambu-Goto theory result for the Polyakov loop correlator, starting from the free bosonic string and using a covariant quantization. The boundary conditions are those of an open string attached to two D0-branes at spatial distance R, in a target space with compact euclidean time. The one-loop free energy contains topo

  14. Jian Song, Ben Weinkove

    Yau conjectured that a Fano manifold admits a Kahler-Einstein metric if and only if it is stable in the sense of geometric invariant theory. There has been much progress on this conjecture by Tian, Donaldson and others. The Mabuchi energy functional plays a central role in these ideas. We study the E_k functionals introduced by X.X. Chen and G. Tian which ge

  15. M. F. Laguna, S. Risau Gusman, J. R. Iglesias

    We study the effect of the social stratification on the wealth distribution on a system of interacting economic agents that are constrained to interact only within their own economic class. The economical mobility of the agents is related to its success in exchange transactions. Different wealth distributions are obtained as a function of the width of the ec

  16. S. Yang, Z. Song, C. P. Sun

    We study the phenomenon of wave packet revivals of Bloch electrons and explore how to control them by a magnetic field for quantum information transfer. It is showed that the single electron system can be modulated into a linear dispersion regime by the "quantized" flux and then an electronic wave packet with the components localized in this regime c

  17. Duiliu-Emanuel Diaconescu, Bogdan Florea, Natalia Saulina

    We develop a vertex formalism for topological string amplitudes on ruled surfaces with an arbitrary number of reducible fibers embedded in a Calabi-Yau threefold. Our construction is based on large N duality and localization with respect to a degenerate torus action. We also discuss potential generalizations of our formalism to a broader class of Calabi-Yau

  18. Giuseppe Bimonte, Enrico Calloni, Giampiero Esposito, Luigi Rosa

    We consider a five-layer Casimir cavity, including a thin superconducting film. We show that when the cavity is cooled below the critical temperature for the onset of superconductivity, the sharp variation (in the microwave region) of the reflection coefficient of the film produces a variation in the value of the Casimir energy. Even though the relative vari

  19. Martin Goldstern, Jakob Kellner

    We give a self-contained proof of the preservation theorem for proper countable support iterations known as "tools-preservation," "Case A" or "first preservation theorem" in the literature. We do not assume that the forcings add reals.

  20. L. Zhang, G. J. Yang, L. X. Xia

    Self-organization effects related to light amplification in the collective atomic recoil laser system with the driven atoms confined in a harmonic trap are investigated further. In the dispersive parametric region, our study reveals that the spontaneously formed structures in the phase space contributes an important role to the light amplification of the pro

  21. Ioannis Papadimitriou, Kostas Skenderis

    We formulate the variational problem for AdS gravity with Dirichlet boundary conditions and demonstrate that the covariant counterterms are necessary to make the variational problem well-posed. The holographic charges associated with asymptotic symmetries are then rederived via Noether's theorem and `covariant phase space' techniques. This allows us

  22. J. Sherson, A. S. Soerensen, J. Fiurasek, K. Moelmer

    We present an experimentally feasible protocol for the complete storage and retrieval of arbitrary light states in an atomic quantum memory using the well-established Faraday interaction between light and matter. Our protocol relies on multiple passages of a single light pulse through the atomic ensemble without the impractical requirement of kilometer long

  23. Brian C. Thomas, Adrian L. Melott, Charles H. Jackman, Claude M. Laird

    Gamma-Ray Bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. We have used a two-dimensional atmospheric model to investigate the effects on the Earth's atmosphere of GRBs delivering a range of fluences, at various latitudes, at the equinoxes and solstices, and at different times of day. We ha

  24. R. Vacher, E. Courtens, M. Foret

    The temperature dependence of the frequency dispersion in the sound velocity and damping of vitreous silica is reanalyzed. Thermally activated relaxation accounts for the sound attenuation observed above 10 K at sonic and ultrasonic frequencies. Its extrapolation to the hypersonic regime reveals that the anharmonic coupling to the thermal bath becomes import

  25. Philippe Mounaix, Pierre Collet, Joel L. Lebowitz

    Solutions to the equation $\partial_t{\cal E}(x,t)-\frac{i}{2m}Δ{\cal E}(x,t)=λ| S(x,t)|^2{\cal E}(x,t)$ are investigated, where $S(x,t)$ is a complex Gaussian field with zero mean and specified covariance, and $m\ne 0$ is a complex mass with ${\rm Im}(m)\ge 0$. For real $m$ this equation describes the backscattering of a smoothed laser beam by an optically

  26. E. Rat, M. Foret, G. Massiera, R. Vialla

    This series discusses the origin of sound damping and dispersion in glasses. In particular, we address the relative importance of anharmonicity versus thermally activated relaxation. In this first article, Brillouin-scattering measurements of permanently densified silica glass are presented. It is found that in this case the results are compatible with a mod

  27. N. C. Tsamis, R. P. Woodard

    During inflation explicit perturbative computations of quantum field theories which contain massless, non-conformal fields exhibit secular effects that grow as powers of the logarithm of the inflationary scale factor. Starobinskii's technique of stochastic inflation not only reproduces the leading infrared logarithms at each order in perturbation theory,

  28. Remi Carles

    We prove some instability phenomena for semi-classical (linear or) nonlinear Schrodinger equations. For some perturbations of the data, we show that for very small times, we can neglect the Laplacian, and the mechanism is the same as for the corresponding ordinary differential equation. Our approach allows smaller perturbations of the data, where the instabi

  29. Par Arvidsson

    We investigate the concept of superconformal symmetry in six dimensions, applied to the interacting theory of (2,0) tensor multiplets and self-dual strings. The action of a superconformal transformation on the superspace coordinates is found, both from a six-dimensional perspective and by using a superspace with eight bosonic and four fermionic dimensions. T

  30. A. Gössling, T. Möller, W. -D. Stein, P. Becker

    We present a detailed study of the phonon modes of the monoclinic compound BiB3O6 based on polarized reflectivity measurements on single crystals. The spectra are analysed by means of a generalized Drude-Lorentz model, which allows us to resolve the modes of A and B symmetry.

  31. Kenju Otsuka, Koji Kamikariya, Takayuki Ohtomo, Seiichi Sudo

    We measured the overall motion of Brownian particles suspended in water by a self-mixing thin-slice solid-state laser with extreme optical sensitivity. From the demodulated signal of laser intensity fluctuations through self-mixing modulations by the interference between the lasing field and Doppler-shifted scattered fields from Brownian particles, it was fo

  32. J. Heinrichs

    We study reflection and transmission of waves in a random tight-binding system with absorption or gain for weak disorder, using a scattering matrix formalism. Our aim is to discuss analytically the effects of absorption or gain on the statistics of wave transport. Treating the effects of absorption or gain exactly in the limit of no disorder, allows us to id

  33. Da-Guan Ke, Qin-Ye Tong

    We present a complexity measure for any finite time series. This measure has invariance under any monotonic transformation of the time series, has a degree of robustness against noise, and has the adaptability of satisfying almost all the widely accepted but conflicting criteria for complexity measurements. Surprisingly, the measure is developed from Kolmogo

  34. M. T. Batchelor, X. W. Guan, N. Oelkers, C. Lee

    We consider the integrable one-dimensional delta-function interacting Bose gas in a hard wall box which is exactly solved via the coordinate Bethe Ansatz. The ground state energy, including the surface energy, is derived from the Lieb-Liniger type integral equations. The leading and correction terms are obtained in the weak coupling and strong coupling regim

  35. Michael H. Seymour

    These lectures on QCD stress the theoretical elements that underlie a wide range of phenomenological studies, particularly gauge invariance, renormalization, factorization and infrared safety. The three parts cover the basics of QCD, QCD at tree level and higher order corrections.

  36. Francois G Schmitt

    We apply a simple method to provide explicit expressions for different scaling exponents in intermittent fully developed turbulence, that before were only given through a Legendre transform. This includes predictability exponents for infinitesimal and non infinitesimal perturbations, Lagrangian velocity exponents, and dispersion exponents. We obtain also new

  37. Shinya Kanemura, Toshihiko Ota, Koji Tsumura

    We study lepton flavor violation (LFV) associated with tau leptons in the framework of the two Higgs doublet model, in which LFV couplings are introduced as a deviation from Model II Yukawa interaction. Parameters of the model are constrained from experimental results and also from requirements of theoretical consistencies such as vacuum stability and pertur

  38. A. Buzdin

    It is demonstrated that in the diffusive superconductor-ferromagnet-superconductor (S/F/S) junctions the current-phase relation is practically sinusoidal everywhere except in a narrow region near the 0-Pi transition. In this region the second harmonic dominates the scenario of the 0-Pi transition. We predict a first order transition for the S/F/S junctions w

  39. Jun O'Hara

    The configuration space of the mechanism of a planar robot is studied. We consider a robot which has $n$ arms such that each arm is of length 1+1 and has a rotational joint in the middle, and that the endpoint of the $k$-th arm is fixed to $Re^{\frac{2(k-1)π}ni}$. Generically, the configuration space is diffeomorphic to an orientable closed surface. Its genu

  40. Katsunori Kubo, Takashi Hotta

    In order to examine the origin of octupole ordering in NpO2, we propose a microscopic model constituted of neptunium 5f and oxygen 2p orbitals. To study multipole ordering, we derive effective multipole interactions from the f-p model by using the fourth-order perturbation theory in terms of p-f hopping integrals. Analyzing the effective model numerically, w

  41. Gianluca Calcagni, Shinji Tsujikawa, M Sami

    We study the cosmological evolution based upon a $D$-dimensional action in low-energy effective string theory in the presence of second-order curvature corrections and a modulus scalar field (dilaton or compactification modulus). A barotropic perfect fluid coupled to the scalar field is also allowed. Phase space analysis and the stability of asymptotic solut

  42. Zeqian Chen, Quanhua Xu

    A necessary and sufficient entanglement criterion based on variances of Mermin-Klyshko's Bell operators is proved for multiqubit pure states. Contrary to Bell's inequalities, entangled pure states strictly satisfy a quadratic inequality but product ones can attain the equality under some local unitary transformations, which can be obtained by solving

  43. Hideo Hasegawa

    By using a semi-analytical dynamical mean-field approximation previously proposed by the author [H. Hasegawa, Phys. Rev. E, {\bf 70}, 066107 (2004)], we have studied the synchronization of stochastic, small-world (SW) networks of FitzHugh-Nagumo neurons with diffusive couplings. The difference and similarity between results for {\it diffusive} and {\it sigmo

  44. Arnold Neumaier

    The collapse challenge for interpretations of quantum mechanics is to build from first principles and your preferred interpretation a complete, observer-free quantum model of the described experiment (involving a photon and two screens), together with a formal analysis that completely explains the experimental result. The challenge is explained in detail, an

  45. B. Bagchi, P. Gorain, C. Quesne, R. Roychoudhury

    By using the point canonical transformation approach in a manner distinct from previous ones, we generate some new exactly solvable or quasi-exactly solvable potentials for the one-dimensional Schrödinger equation with a position-dependent effective mass. In the latter case, SUSYQM techniques provide us with some additional new potentials.

  46. Tomohiro Ogawa

    A simple and unifying method to show the perfect error-correcting condition is provided based on the quantum mutual information. The one-to-one parameterization of quantum operations and the properties of the quantum relative entropy are used effectively in this paper, where the equivalence between the subspace transmission and the entanglement transmission

  47. John Martin, Thierry Bastin

    A short review of the theoretical studies of the cold atom micromaser (mazer) is presented. Existing models are then improved by considering more general working conditions. Especially, the mazer physics is investigated in the situation where a detuning between the cavity mode and the atomic transition frequency is present. Interesting new effects are pointe

  48. A. Kawaguchi, K. Shimizu, Y. Tokura, N. Imoto

    Using the tensor product representation in the density matrix renormalization group, we show that a quantum circuit of Grover's algorithm, which has one-qubit unitary gates, generalized Toffoli gates, and projective measurements, can be efficiently simulated by a classical computer. It is possible to simulate quantum circuits with several ten qubits.

  49. N. L. Harshman

    In several recent papers on entanglement in relativistic quantum systems and relativistic Bell's inequalities, relativistic Bell-type two-particle states have been constructed in analogy to non-relativistic states. These constructions do not have the form suggested by relativistic invariance of the dynamics. Two relativistic formulations of Bell-type sta

  50. Catherine Beauchemin

    Viral kinetics have been extensively studied in the past through the use of spatially well-mixed ordinary differential equations describing the time evolution of the diseased state. However, emerging spatial structures such as localized populations of dead cells might adversely affect the spread of infection, similar to the manner in which a counter-fire can

  51. Yunhai Cai, Yuri Nosochkov

    The leading Lie generators, including the chromatic effects, due to hard-edge fringe field of single multipole and solenoid are derived from the vector potentials within a Hamiltonian system. These nonlinear generators are applied to the interaction region of PEP-II to analyze the linear errors due to the feed-down from the off-centered quadrupoles and solen

  52. Francisco A. Rodrigues, Luciano da F. Costa

    The Sznajd model has been largely applied to simulate many sociophysical phenomena. In this paper we applied the Sznajd model with more than two opinions on three different network topologies and observed the evolution of surviving opinions after many interactions among the nodes. As result, we obtained a scaling law which depends of the network size and the

  53. F. Sattin, N. Vianello

    The Probability Distribution Function of plasma density fluctuations at the edge of fusion devices is known to be skewed and strongly non-Gaussian. The causes of this peculiar behaviour are, up to now, largely unexplored. On the other hand, understanding the origin and the properties of edge turbulence is a key issue in magnetic fusion research. In this work

  54. K. Staliunas, C. Serrat, R. Herrero, C. Cojocaru

    We investigate propagation of light pulses in photonic crystals in the vicinity of the zero-diffraction point. We show that Gaussian pulses due to nonzero width of their spectrum spread weakly in space and time during the propagation. We also find the family of nonspreading pulses, propagating invariantly in the vicinity of the zero diffraction point of phot

  55. Erasmo Recami

    We present here a panoramic view of our unified, bi-scale theory of gravitational and strong interactions [which is mathematically analogous to the last version of N.Rosen's bi-metric theory, and yields physical results similar to strong gravity's]. This theory, developed during the last 25 years, is purely geometrical in nature, adopting the methods of gene

  56. Andrew W. Steiner, Madappa Prakash, James M. Lattimer, Paul J. Ellis

    The roles of isospin asymmetry in nuclei and neutron stars are investigated using a range of potential and field-theoretical models of nucleonic matter. The parameters of these models are fixed by fitting the properties of homogeneous bulk matter and closed-shell nuclei. We discuss and unravel the causes of correlations among the neutron skin thickness in he

  57. Mark Heinz

    We present measurements of the transverse momentum spectra for K0s, Lambda, Xi and their antiparticles in p+p collisions at $\sqrt{s}=200$ GeV. The extracted mid-rapidity yields and <pT> are in agreement with previous $p+\bar{p}$ experiments while they have smaller statistical errors. We compare the measured particle spectra and <pT> values to predictions fr

  58. J. J. Kelly

    We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W=1.23 GeV at Q^2=1.0 (GeV/c)^2, obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interferenc

  59. S. Schadmand

    Differences in the photoproduction of mesons on the free proton and on nuclei are expected to reveal changes in the properties of hadrons. Inclusive studies of nuclear photoabsorption have provided evidence of medium modifications. However, the results have not been explained in a model independent way. A deeper understanding of the situation is anticipated

  60. U. E. Vincent, A. Kenfack, A. N. Njah, O. Akinlade

    The bifurcation and chaotic behaviour of unidirectionally coupled deterministic ratchets is studied as a function of the driving force amplitude ($a$) and frequency ($ω$). A classification of the various types of bifurcations likely to be encountered in this system was done by examining the stability of the steady state in linear response as well as construc

  61. Roberto Miatello, Ricardo Podesta

    We study the spectral properties of a large class of compact flat Riemannian manifolds of dimension 4, namely, those whose corresponding Bieberbach groups have the canonical lattice as translation lattice. By using the explicit expression of the heat trace of the Laplacian acting on $p$-forms, we determine all $p$-isospectral and $L$-isospectral pairs and we

  62. Ashkan Nikeghbali

    This note deals with the question: what remains of the Burkholder-Davis-Gundy inequalities when stopping times $T$ are replaced by arbitrary random times $ρ$? We prove that these inequalities still hold when $T$ is a pseudo-stopping time and never holds for ends of predictable sets.

  63. Ross Geoghegan, Fernando Guzman

    Given a set S equipped with a binary operation (we call this a &#34;bracket algebra&#34;) one may ask to what extent the binary operation satisfies some of the consequences of the associative law even when it is not actually associative? We define a subgroup Assoc(S) of Thompson&#39;s Group F for each bracket algebra S, and we interpret the size of Assoc(S)

  64. Thorsten Holm, Wei Hu

    The representation dimension was defined by M. Auslander in 1970 and is, due to spectacular recent progress, one of the most interesting homological invariants in representation theory. The precise value is not known in general, and is very hard to compute even for small examples. For group algebras, it is known in the case of cyclic Sylow subgroups, due to

  65. Alain Connes, Henri Moscovici

    This is primarily a survey of the way in which Hopf cyclic cohomology has emerged and evolved, in close relationship with the application of the noncommutative local index formula to transverse index theory on foliations. Being Diff-invariant, the geometric framework that allowed us to treat the `space of leaves&#39; of a general foliation provides a `backgr

  66. Nero Budur, Mircea Mustata, Morihiko Saito

    We give a combinatorial description of the roots of the Bernstein-Sato polynomial of a monomial ideal using the Newton polyhedron and some semigroups associated to the ideal.

  67. Nero Budur, Mircea Mustata, Morihiko Saito

    We describe the roots of the Bernstein-Sato polynomial of a monomial ideal using reduction mod p and invariants of singularities in positive chracteristic. We give in this setting a positive answer to a problem of Takagi, Watanabe and the second author, concerning the dependence on the characteristic for these invariants of singularities.

  68. Bo Berndtsson

    In a previous paper, \cite{Berndtsson}, we have studied a property of subharmonic dependence on a parameter of Bergman kernels for a family of weighted $L^2$-spaces of holomorphic functions. Here we prove a result on the curvature of a vector bundle defined by this family of $L^2$-spaces itself, which has the earlier results on Bergman kernels as a corollary

  69. Bo Berndtsson

    Let $D$ be a pseudoconvex domain in $\C^k_t\times\Cn_z$ and let $ϕ$ be a plurisubharmonic function in $D$. For each $t$ we consider the $n$-dimensional slice of $D$, $D_t=\{z; (t,z)\in D\}$, let $ϕ^t$ be the restriction of $ϕ$ to $D_t$ and denote by $K_t(z,ζ)$ the Bergman kernel of $D_t$ with the weight function $ϕ^t$. Generalizing a recent result of Maitani

  70. Ahad Rahimi

    The Hilbert functions and the regularity of the graded components of local cohomology of a bigraded algebra are considered. Explicit bounds for these invariants are obtained for bigraded hypersurface rings.

  71. Tokuji Araya, Ryo Takahashi, Yuji Yoshino

    Cohen-Macaulay dimension for modules over a commutative noetherian local ring has been defined by A. A. Gerko. That is a homological invariant sharing many properties with projective dimension and Gorenstein dimension. The main purpose of this paper is to extend the notion of Cohen-Macaulay dimension for modules over commutative noetherian local rings to tha

  72. F. J. Castro-Jimenez, M. Granger

    Let M be a coherent module over the ring D of linear differential operators on an analytic manifold X and let us consider k germs of transverse hypersurfaces at a point x in X. The Malgrange-Kashiwara V-filtrations along these hypersurfaces, associated with a given presentation of the germ of M at the point x, give rise to a multifiltration U(M) of M_x intro

  73. Armengol Gasull, Hector Giacomini, Joan Torregrosa

    We consider a system of the form x&#39;=P_n(x,y)+xR_m(x,y), y&#39;=Q_n(x,y)+yR_m(x,y), where P_n(x,y), Q_n(x,y) and R_m(x,y) are homogeneous polynomials of degrees n, n and m, respectively, with n<=m. We prove that this system has at most one limit cycle and that when it exists it can be explicitly found. Then we study a particular case, with n=3 and m=4. We

  74. Weimin Sheng, Neil S Trudinger, Xu-jia Wang

    Let M be a compact Riemannian manifold of dimension n. The k-curvature, for k=1,2,..n, is defined as the k-th elementary symmetric polynomial of the eigenvalues of the Schouten tenser. The k-Yamabe problem is to prove the existence of a conformal metric whose k-curvature is a constant. When k=1, it reduces to the well-known Yamabe problem. Under the assumpti

  75. Loredana Lanzani, Luca Capogna, Russell Brown

    We consider the mixed problem for the Laplace operator in a class of Lipschitz graph domains in two dimensions with Lipschitz constant at most 1. The boundary of the domain is decomposed into two disjoint sets D and N. We suppose the Dirichlet data, f_D has one derivative in L^p(D) of the boundary and the Neumann data is in L^p(N). We find conditions on the

  76. Misja Nuyens, Bert Zwart

    We consider a GI/GI/1 queue with the shortest remaining processing time discipline (SRPT) and light-tailed service times. Our interest is focused on the tail behavior of the sojourn-time distribution. We obtain a general expression for its large-deviations decay rate. The value of this decay rate critically depends on whether there is mass in the endpoint of

  77. Elchanan Mossel, Ryan O&#39;Donnell, Krzysztof Oleszkiewicz

    In this paper we study functions with low influences on product probability spaces. The analysis of boolean functions with low influences has become a central problem in discrete Fourier analysis. It is motivated by fundamental questions arising from the construction of probabilistically checkable proofs in theoretical computer science and from problems in t

  78. Kiran S. Kedlaya

    This primarily expository article collects together some facts from the literature about the monodromy of differential equations on a p-adic (rigid analytic) annulus, though often with simpler proofs. These include Matsuda&#39;s classification of quasi-unipotent nabla-modules, the Christol-Mebkhout construction of the ramification filtration, and the Christo

  79. Bernardo Lafuerza-Guillen, Jose L. Rodriguez

    The motivation of this paper is a suggestion by Höle of comparing the notions of $\D$-boundedness and boundedness in Probabilistic Normed spaces (briefly PN spaces), with non necessarily continuous triangle functions. Such spaces are here called ``pre-PN spaces&#39;&#39;. Some results on Šerstnev spaces due to B. Lafuerza, J. A. Rodriguez, and C. Sempi, are

  80. Jiayuan Lin

    In this paper, we prove that the family of $\Bbb Q$-Fano threefolds with Picard number one is birationally unbounded.

  81. E. L. Graca, I. V. Vancea

    In this letter we propose a new ansatz for the thermal string in the TFD formulation. From it, we derive the thermal vacuum for the closed bosonic string and calculate the thermal partition function in the blackhole $AdS$ background in the first order of the perturbative quantization.

  82. Sergei Gukov, Kirill Saraikin, Cumrun Vafa

    Using the recent observations of the relation between Hartle-Hawking wave function and topological string partition function, we propose a wave function for scalar metric fluctuations on S^3 embedded in a Calabi-Yau. This problem maps to a study of non-critical bosonic string propagating on a circle at the self-dual radius. This can be viewed as a stringy to

  83. Gaston Giribet, Yu Nakayama

    Recently, Ribault and Teschner pointed out the existence of a one-to-one correspondence between N-point correlation functions for the SL(2,C)_k/SU(2) WZNW model on the sphere and certain set of 2N-2-point correlation functions in Liouville field theory. This result is based on a seminal work by Stoyanovsky. Here, we discuss the implications of this correspon

  84. Sophie de Buyl, Laurent Houart, Nassiba Tabti

    The G++ content of the formulation of gravity and M-theories as very-extended Kac-Moody invariant theories is further analysed. The different exotic phases of all the G_B++ theories, which admit exact solutions describing intersecting branes smeared in all directions but one, are derived. This is achieved by analysing for all G++ the signatures which are rel

  85. Branislav Sazdovic

    In the present article, we study the local features of the world-sheet in the case when probe bosonic string moves in antisymmetric background field. We generalize the geometry of surfaces embedded in space-time to the case when the torsion is present. We define the mean extrinsic curvature for spaces with Minkowski signature and introduce the concept of mea

  86. Sanjeev S. Seahra

    Motivated by stringy considerations, Randall & Sundrum have proposed a model where all the fields and particles of physics, save gravity, are confined on a 4-dimensional brane embedded in 5-dimensional anti-deSitter space. Their scenario features a stable bound state of bulk gravity waves and the brane that reproduces standard general relativity. We demonstr

  87. A. A. Slavnov

    An explicitely gauge invariant polynomial action for massive gauge fields is proposed. For different values of parameters it describes massive Yang-Mills field, the Higgs-Kibble model, the model with spontaneously broken symmetry and two scalar mesons.

  88. Shinji Hamamoto

    Possible nonlinear completion of massive gravity is presented. An additional scalar ghost contained in linear theory condensates to give rise to positive-energy excitations.

  89. V. Parihar, A. Widom, Y. N. Srivastava

    In a model of relativistic heavy ion collisions wherein the unconfined quark-gluon plasma is condensed into glass, we derive the Vogel-Fulcher-Tammann cooling law. This law is well known to hold true in condensed matter glasses. The high energy plasma is initially created in a very hot negative temperature state and cools down to the Hagedorn glass temperatu

  90. T. Melde, W. Plessas, R. F. Wagenbrunn

    We present covariant predictions for pi and eta decay modes of N and Delta resonances from relativistic constituent-quark models based on one-gluon-exchange and Goldstone-boson-exchange dynamics. The results are calculated within the point-form approach to Poincare-invariant relativistic quantum mechanics applying a spectator-model decay operator. The direct

  91. L. Cunqueiro, E. G. Ferreiro, F. del Moral, C. Pajares

    We present our results on multiplicity fluctuations in the framework of the string clustering approach. We compare our results --with and without clustering formation-- with CERN SPS NA49 data. We find a non-monotonic behaviour of these fluctuations as a function of the collision centrality, which has the same origin as the observed fluctuations of transvers

  92. A. E. Dorokhov

    The correlator of singlet axial-vector and vector currents in the external electromagnetic field is studied within the instanton liquid model of QCD vacuum. In the chiral limit we calculate the longitudinal w_L^0 and transversal w_T^0 with respect to axial-vector index invariant amplitudes at arbitrary momentum transfer q. It is demonstrated how the anomalou

  93. P. Colangelo, F. De Fazio, A. Ozpineci

    We study radiative decays of $D^*_{sJ}(2317)$ and $D_{sJ}(2460)$ using light-cone QCD sum rules. In particular, we consider the decay modes $D^*_{sJ}(2317)\to D_s^* γ$ and $D_{sJ}(2460)\to D_s^{(*)} γ, D^*_{sJ}(2317) γ$ and evaluate the hadronic parameters in the transition amplitudes analyzing correlation functions of scalar, pseudoscalar, vector and axial-

  94. Guy Engelhard, Yosef Nir, Guy Raz

    The CP asymmetry in the $B \to K_S K_S K_S$ decay is being measured by the two B factories. A large deviation of the CP asymmetry $S_{K_S K_S K_S}$ from $-S_{ψK_S}$ and/or of $C_{K_S K_S K_S}$ from zero would imply new physics in $b \to s$ transitions. We try to put upper bounds on the Standard Model size of these deviations, using SU(3) flavor relations and

  95. S. Digal, O. Kaczmarek, F. Karsch, H. Satz

    We study the free energy of a heavy quark-antiquark pair in a thermal medium. We constuct a simple ansatz for the free energy for two quark flavors motivated by the Debye-Hückel theory of screening.

  96. Masataka Okamoto

    We use lattice QCD to fully determine the CKM matrix. |V_{cd}|, |V_{cs}|, |V_{ub}|, |V_{cb}| and |V_{us}| are, respectively, directly determined with recent lattice results for form factors of semileptonic D->pi l nu, D->K l nu, B->pi l nu, B->D l nu and K->pi l nu decays obtained by the Fermilab Lattice, MILC, and HPQCD Collaborations. In addition, |V_{ud}|

  97. Alex Smith

    This paper describes recent preliminary results from the CLEO-c experiment using an initial ~60 pb^-1 sample of data collected in e^+e^- collisions at a center of mass energy around the mass of the psi(3770). A first measurement of the branching fraction BR(D^+ -> mu^+ nu) = (3.5 +/- 1.4 +/- 0.6)x 10^-4 and the corresponding decay constant f_D = (202 +/- 41

  98. Katsumi Senyo

    We report studies in polarization in B decay into two vector mesons with data equivalent to $253 {\rm fb^{-1}}$ on $Υ(4S)$ resonance at KEKB. In $B^0 \to ϕK^{*0}$, $B^+ \to ϕK^{*+}$ and $B^+ \to ρ^+ K^{*0}$ decays, we determine $f_L = 0.45 \pm 0.05({\rm stat.}) \pm 0.02({\rm syst.})$, $f_L = 0.52 \pm 0.08({\rm stat.}) \pm 0.03({\rm syst.})$ and $f_L = 0.43 \

  99. Saulo Carneiro

    Among the suggested solutions to the cosmological constant problem, we find the idea of a dynamic vacuum, with an energy density decaying with the universe expansion. We investigate the possibility of a variation in the gravitational constant as well, induced, at the cosmological scale, by the vacuum decay. We consider an effective Brans-Dicke theory in the

  100. M. D. Maia

    The information loss paradox for Schwarzschild black holes is examined, using the ADS/CFT correspondence extended to the $M_6 (4,2)$ bulk. It is found that the only option compatible with the preservation of the quantum unitarity is when a regular remnant region of the black hole survives to the black hole evaporation process, where information can be stored