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September 2006 arXiv papers

Showing 1100 of 4,533 papers

  1. Jean-Paul Blaizot, Andreas Ipp, Ramon Mendez-Galain, Nicolas Wschebor

    We use the non-perturbative renormalization group to clarify some features of perturbation theory in thermal field theory. For the specific case of the scalar field theory with O(N) symmetry, we solve the flow equations within the local potential approximation. This approximation reproduces the perturbative results for the screening mass and the pressure up

  2. R. G. Edwards, G. Fleming, Ph. Hagler, J. W. Negele

    Moments of unpolarized, helicity, and transversity distributions, electromagnetic form factors, and generalized form factors of the nucleon are presented from a preliminary analysis of lattice results using pion masses down to 359 MeV. The twist two matrix elements are calculated using a mixed action of domain wall valence quarks and asqtad staggered sea qua

  3. Yu. G. Prokhorov

    We prove that the degree of Fano threefolds with terminal Q-factorial singularities and Picard number one is at most 125/2 and the bound is sharp.

  4. Eddy Mayer-Wolf, Moshe Zakai

    The model considered is that of ``signal plus white noise.'' Known connections between the noncausal filtering error and mutual information are combined with new ones involving the causal estimation error, in a general abstract setup. The results are shown to be invariant under a wide class of causality patterns; they are applied to the derivation of

  5. Emmanuel Kowalski

    We describe a very general abstract form of sieve based on a large sieve inequality which generalizes both the classical sieve inequality of Montgomery (and its higher-dimensional variants), and our recent sieve for Frobenius over function fields. The general framework suggests new applications. We get some first results on the number of prime divisors of ``

  6. Antonio O. Bouzas

    A mechanism is discussed to obtain light scalar fields from a spontaneously broken continuous symmetry without explicitly breaking it. If there is a continuous manifold of classical vacua in orbit space, its tangent directions describe classically massless fields that may acquire mass from perturbations of the potential that do not break the symmetry. We con

  7. Benjamin D. Greenbaum, Salman Habib, Kosuke Shizume, Bala Sundaram

    We elucidate the basic physical mechanisms responsible for the quantum-classical transition in one-dimensional, bounded chaotic systems subject to unconditioned environmental interactions. We show that such a transition occurs due to the dual role of noise in regularizing the semiclassical Wigner function and averaging over fine structures in classical phase

  8. Thom Sulanke, Frank H. Lutz

    We present a fast enumeration algorithm for combinatorial 2- and 3-manifolds. In particular, we enumerate all triangulated surfaces with 11 and 12 vertices and all triangulated 3-manifolds with 11 vertices. We further determine all equivelar polyhedral maps on the non-orientable surface of genus 4 as well as all equivelar triangulations of the orientable sur

  9. J. Kaupuzs

    The perturbative renormalization of the Ginzburg-Landau model is reconsidered based on the Feynman diagram technique. We derive renormalization group (RG) flow equations, exactly calculating all vertices appearing in the perturbative renormalization of the phi^4 model up to the epsilon^3 order of the epsilon-expansion. In this case, the phi^2, phi^4, phi^6,

  10. Y. Nikolayevsky

    We classify solvable Lie groups with a free nilradical admitting an Einstein left-invariant metric. Any such group is essentially determined by the nilradical of its Lie algebra, which is then called an Einstein nilradical. We show that among the free Lie algebras, there are very few Einstein nilradicals. Except for the one-step (abelian) and the two-step on

  11. J. C. Eilbeck, V. Z. Enolski, S. Matsutani, Y. Ônishi

    We develop the theory of generalized Weierstrass sigma- and \wp-functions defined on a trigonal curve of genus three. In particular we give a list of the associated partial differential equations satisfied by the \wp-functions, a proof that the coefficients of the power series expansion of the sigma-function are polynomials of moduli parameters, and the deri

  12. F. A. Gareev, I. E. Zhidkova

    We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schrodinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is (are) not known or these equations ca

  13. K. Farakos, P. Pasipoularides

    We study the case of brane world models with an additional Gauss-Bonnet term in the presence of a bulk scalar field which interacts non-minimally with gravity, via a possible interaction term of the form $-1/2 ξR ϕ^2$. The Einstein equations and the junction conditions on the brane are formulated, in the case of the bulk scalar field. Static solutions of thi

  14. Y. H. Ahn, Sin Kyu Kang, C. S. Kim, Jake Lee

    We consider a $μ-τ$ symmetry in neutrino sectors realized at GUT scale in the context of a seesaw model. In our scenario, the exact $μ-τ$ symmetry realized in the basis where the charged lepton and heavy Majorana neutrino mass matrices are diagonal leads to vanishing lepton asymmetries. We find that, in the minimal supersymmetric extension of the seesaw mode

  15. M. Gubinelli

    We show how to apply ideas from the theory of rough paths to the analysis of low-regularity solutions to non-linear dispersive equations. Our basic example will be the one dimensional Korteweg--de Vries (KdV) equation on a periodic domain and with initial condition in $\FF L^{α,p}$ spaces. We discuss convergence of Galerkin approximations, a modified Euler s

  16. Attila Szolnoki, Gyorgy Szabo

    Evolutionary Prisoner's Dilemma games with quenched inhomogeneities in the spatial dynamical rules are considered. The players following one of the two pure strategies (cooperation or defection) are distributed on a two-dimensional lattice. The rate of strategy adoption from a randomly chosen neighbors are controlled by the payoff difference and a two-va

  17. Kenichiro Tanabe, Hiromichi Yamada

    We study the fixed point subalgebra of a certain class of lattice vertex operator algebras by an automorphism of order 3, which is a lift of a fixed-point-free isometry of the underlying lattice. We classify the irreducible modules for the subalgebra. Moreover, the rationality and the $C_2$-cofiniteness of the subalgebra are established. Our result contains

  18. Tetsuo Deguchi

    We present a necessary and sufficient condition for a finite-dimensional highest weight representation of the $sl_2$ loop algebra to be irreducible. In particular, for a highest weight representation with degenerate parameters of the highest weight, we can explicitly determine whether it is irreducible or not. We also present an algorithm for constructing fi

  19. Zhi-Ping Jin, Ting Yan, Yi-Zhong Fan, Da-Ming Wei

    In the double neutron star merger or neutron star-black hole merger model for short GRBs, the outflow launched might be mildly magnetized and neutron rich. The magnetized neutron-rich outflow will be accelerated by the magnetic and thermal pressure and may form a two component jet finally, as suggested by Vlahakis, Peng & Königl (2003). We show in this work

  20. C. Burdik, S. Krivonos, A. Shcherbakov

    It is presented a method of construction of sigma-models with target space geometries different from conformally flat ones. The method is based on a treating of a constancy of a coupling constant as a dynamical constraint following as an equation of motion. In this way we build N=4 and N=8 supersymmetric four-dimensional sigma-models in d=1 with hyper-Kahler

  21. Chong-Xing Yue, Li Li, Shuo Yang, Li-Na Wang

    Littlest Higgs model with T-parity predicts the existence of the neutral, weakly interacting, new gauge boson $B_{H}$, which can be seen as an attractive dark matter candidate. We study production of the new gauge boson $B_{H}$ via $eγ$ and $ep$ collisions. We find that $B_{H}$ can be abundantly produced via the subprocesses $e^{-}γ\to L^{-}B_{H}$ and $γq\to

  22. Ying-Qiu Gu

    The standard spinor connection in curved space-time is represented in a compact form. In this form the calculation is complicated, and its physical effects are concealed. In this paper, we split spinor connection into two vectors $\Upsilon_\mu$ and $\Omega_\mu$, where $\Upsilon_\mu$ is only related to geometrical calculations, but $\Omega_\mu$ leads to dynam

  23. Andrei Radulescu-Banu

    We define Anderson-Brown-Cisinski (ABC) cofibration categories, and construct homotopy colimits of diagrams of objects in ABC cofibration categories. Homotopy colimits for Quillen model categories are obtained as a particular case. We attach to each ABC cofibration category a left Heller derivator. A dual theory is developed for homotopy limits in ABC fibrat

  24. Garry Bowen, Nilanjana Datta

    The information spectrum approach gives general formulae for optimal rates of various information theoretic protocols, under minimal assumptions on the nature of the sources, channels and entanglement resources involved. This paper culminates in the derivation of the dense coding capacity for a noiseless quantum channel, assisted by arbitrary shared entangle

  25. Pankaj Agrawal, Arun Pati

    True tripartite entanglement of the state of a system of three qubits can be classified on the basis of stochastic local operations and classical communications (SLOCC). Such states can be classified in two categories: GHZ states and W-states. It is known that GHZ states can be used for teleportation and superdense coding, but the prototype W-state cannot be

  26. F. Karstens, S. Trippel

    A programmable trigger logic module (TRILOMO) was implemented successfully in an FPGA using their internal look-up tables to save Boolean functions. Up to 16 trigger input signals can be combined logically for a fast trigger decision. The new feature is that the trigger decision is VME register based. The changes are made without modifying the FPGA code. Add

  27. PHOBOS Collaboration, B. B. Back, M. D. Baker, M. Ballintijn

    Transverse momentum spectra of pions, kaons, protons and antiprotons from Au+Au collisions at sqrt(s_(NN)) = 62.4 GeV have been measured by the PHOBOS experiment at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The identification of particles relies on three different methods: low momentum particles stopping in the first detector lay

  28. A. A. Koronovskii, P. V. Popov, A. E. Hramov

    Generalized synchronization is analyzed in unidirectionally coupled oscillatory systems exhibiting spatiotemporal chaotic behavior described by Ginzburg-Landau equations. Several types of coupling betweenthe systems are analyzed. The largest spatial Lyapunov exponent is proposed as a new characteristic of the state of a distributed system, and its calculatio

  29. Boris Kolev

    This paper is a survey article on bi-Hamiltonian systems on the dual of the Lie algebra of vector fields on the circle. We investigate the special case where one of the structures is the canonical Lie-Poisson structure and the second one is constant. These structures called affine or modified Lie-Poisson structures are involved in the integrability of certai

  30. Takeshi Suzuki

    We investigate the representation theory of the rational and trigonometric Cherednik algebra of type $GL_n$ by means of combinatorics on periodic (or cylindrical) skew diagrams. We introduce and study standard tableaux and plane partitions on periodic diagrams, and in particular, compute some generating functions concerning plane partitions, where Kostka pol

  31. Marian Ioan Munteanu

    In this paper we study a Riemanian metric on the tangent bundle $T(M)$ of a Riemannian manifold $M$ which generalizes the Cheeger Gromoll metric and a compatible almost complex structure which together with the metric confers to $T(M)$ a structure of locally conformal almost Kählerian manifold. We found conditions under which $T(M)$ is almost Kählerian, loca

  32. Mark Elin, Marina Levenshtein, Simeon Reich, David Shoikhet

    Let $S_{1}=\left\{F_t\right\}_{t\geq 0}$ and $S_{2}=\left\{G_t\right\}_{t\geq 0}$ be two continuous semigroups of holomorphic self-mappings of the unit disk $Δ=\{z:|z|<1\}$ generated by $f$ and $g$, respectively. We present conditions on the behavior of $f$ (or $g$) in a neighborhood of a fixed point of $S_{1}$ (or $S_{2}$), under which the commutativity of

  33. Elena Trofimchuk, Sergei Trofimchuk

    We consider equation $u_t(t,x) = Δu(t,x)- u(t,x) + g(u(t-h,x)) (*) $, when $g:\R_+\to \R_+$ has exactly two fixed points: $x_1= 0$ and $x_2=κ>0$. Assuming that $g$ is unimodal and has negative Schwarzian, we indicate explicitly a closed interval $\mathcal{C} = \mathcal{C}(h,g&#39;(0),g&#39;(κ)) = [c_*,c^*]$ such that $(*)$ has at least one (possibly, nonmono

  34. J. A. Rodriguez, J. M. Sigarreta

    An offensive alliance in a graph $Γ=(V,E)$ is a set of vertices $S\subset V$ where for every vertex $v$ in its boundary it holds that the majority of vertices in $v$&#39;s closed neighborhood are in $S$. In the case of strong offensive alliance, strict majority is required. An alliance $S$ is called global if it affects every vertex in $V\backslash S$, that

  35. H. Ammari, H. Kang, H. Lee

    We investigate the band-gap structure of the frequency spectrum for elastic waves in a high-contrast, two-component periodic elastic medium. We consider two-dimensional phononic crystals consisting of a background medium which is perforated by an array of holes periodic along each of the two orthogonal coordinate axes. In this paper we establish a full asymp

  36. Marie-Francoise Bidaut-Veron, Rouba Borghol, Laurent Veron

    We extend some classical results dealing with boundary Harnack inequatilities to a class of quasilinear elliptic equations and derive some new estimates for solutions of such equations with an isolated singularity on the boundary of a domain.

  37. Rouba Borghol, Laurent Veron

    We construct N-harmonic functions in a domain with one isolated singularity on the boundary of the domain. By using solutions of the spherical p-harmonic spectral problem, we give an inductive method to produce a large variety of separable p-harmonic functions.

  38. Enrique Arrondo

    We provide an elementary proof of the Hartshorne-Serre correspondence for constructing vector bundles from local complete intersection subschemes of codimension two. This will be done, as in the correspondence of hypersurfaces and line bundles, by patching together local determinantal equations in order to produce sections of a vector bundle.

  39. Vladimir S. Zhgoon

    We study a variation of Mumford&#39;s quotient for the action of a maximal torus $T$ on a flag variety $G/B$ depending on projective embedding $G/B \hookrightarrow \Bbb P(V(χ))$, where $T$-linearization is induced by the standard $G$-linearization. We describe the linear spans of the supports of semistable orbits, that allow us to calculate the rank of the P

  40. Arash Rastegar

    This paper is devoted to deformation theory of &#34;anabelian&#34; representations of the absolute Galois group landing in outer automorphism group of the algebraic fundamental group of a hyperbolic smooth curve defined over a number-field. In the first part of this paper, we obtained universal deformations for Lie-algebra versions of the above representatio

  41. Jorge Betancor, Liliana Forzani, Roberto Scotto, Wilfredo Urbina

    In this note we consider the maximal function for the generalized Ornstein-Uhlenbeck semigroup in $\RR$ associated with the generalized Hermite polynomials $\{H_n^μ\}$ and prove that it is weak type (1,1) with respect to $dλ_μ(x) = |x|^{2μ}e^{-|x|^2} dx,$ for $μ>-1/2$ as well as bounded on $L^p(dλ_μ) $ for $p>1$

  42. Dave Witte Morris, Joy Morris, Kerri Webb

    Let D be the circulant digraph with n vertices and connection set {2,3,c}. (Assume D is loopless and has outdegree 3.) Work of S.C.Locke and D.Witte implies that if n is a multiple of 6, c is either (n/2) + 2 or (n/2) + 3, and c is even, then D does not have a hamiltonian cycle. For all other cases, we construct a hamiltonian cycle in D.

  43. Kenneth S. Alexander

    We consider a polymer, with monomer locations modeled by the trajectory of a Markov chain, in the presence of a potential that interacts with the polymer when it visits a particular site 0. We assume that probability of an excursion of length $n$ is given by $n^{-c}ϕ(n)$ for some $1<c<2$ and slowly varying $ϕ$. Disorder is introduced by having the interactio

  44. Ursula Hamenstaedt

    Let X be an arbitrary hyperbolic geodesic metric space and let G be a countable non-elementary weakly acylindrical group of isometries of X. We show that the second bounded cohomology group of G with real coefficients or with coefficients in the regular representation is infinite dimensional. The result holds for any subgroup of the mapping class group of a

  45. Arash Rastegar

    To a hyperbolic smooth curve defined over a number-field one naturally associates an &#34;anabelian&#34; representation of the absolute Galois group of the base field landing in outer automorphism group of the algebraic fundamental group. In this paper, we introduce several deformation problems for Lie-algebra versions of the above representation and show th

  46. Arpad Hegedus, Francesco Ravanini, Junji Suzuki

    We present the coupled nonlinear integral equations (NLIE) governing the finite size effects in N=1 super sine-Gordon model for the vacuum as well as for the excited states. Their infrared limit correctly yields the scattering data of the super sine-Gordon S-matrix conjectured by Ahn. Ultraviolet analysis is in agreement with the expected conformal data of c

  47. Axel Maas

    The relation of confinement scenarios based on topological configurations and the Gribov-Zwanziger scenario is examined. To this end the eigenspectrum of the central operator in the Gribov-Zwanziger scenario, the Faddeev-Popov operator, is studied in topological field configurations. It is found that instantons, monopoles, and vortices contribute to the spec

  48. A. Denbleyker, D. Du, Y. Meurice, M. Naides

    The notion of a non-perturbative effect is ambiguous if it requires the subtraction of a perturbative part defined by a diverging series. A common procedure consists in dropping the order of minimal contribution and the higher orders. This allows us to isolate very accurately the one-instanton effect for the double-well potential. For the one plaquette gauge

  49. Axel Maas, Attilio Cucchieri, Tereza Mendes

    Non-perturbative properties of QCD, such as color confinement, are encoded in the infrared behavior of correlation functions, e.g. propagators and vertices. Various analytic predictions have been suggested for these quantities in various gauges. Here we numerically test these predictions using lattice gauge theory. In particular, we present results for the 2

  50. Maarten Golterman, Elisabetta Pallante

    The transformation properties of strong penguin operators under the action of the flavor group change when they are considered as operators in (partially) quenched QCD instead of the unquenched theory. An ambiguity arises, which is parameterized by new low-energy constants in the effective theory describing non-leptonic kaon decays in the (partially) quenche

  51. Noriyoshi ISHII, Sinya AOKI, Tetsuo HATSUDA

    The first lattice QCD result on the nuclear force (the NN potential) is presented in the quenched level. The standard Wilson gauge action and the standard Wilson quark action are employed on the lattice of the size 16^3\times 24 with the gauge coupling beta=5.7 and the hopping parameter kappa=0.1665. To obtain the NN potential, we adopt a method recently pro

  52. S. Aogaki, I. Moritani, T. Sugai, F. Takeutchi

    We developed novel conditional expressions (CEs) for Lane and Bates&#39; blind deconvolution. The CEs are given in term of the derivatives of the zero-values of the z-transform of given images. The CEs make it possible to automatically detect multiple blur convolved in the given images all at once without performing any analysis of the zero-sheets of the giv

  53. M. D. Girardeau

    The ground and excited states of a one-dimensional (1D) spin-1/2 Fermi gas (SFG) with both attractive zero-range odd-wave interactions and repulsive zero-range even-wave interactions are mapped exactly to a 1D Lieb-Liniger-Heisenberg (LLH) model with delta-function repulsions depending on isotropic Heisenberg spin-spin interactions, such that the complete SF

  54. Ramaz Khomeriki, Stefano Ruffo, Sandro Wimberger

    Coherent macroscopic tunneling of a Bose-Einstein condensate between two parts of an optical lattice separated by an energy barrier is theoretically investigated. We show that by a pulsewise change of the barrier height, it is possible to switch between tunneling regime and a self-trapped state of the condensate. This property of the system is explained by e

  55. F. Kh. Akopov, I. V. Chkhartishvili, V. M. Gabunia, G. I. Mamniashvili

    It is presented some technological parameters and physical characteristics of Fe - Ni - Al composite materials, fabricated by pressing with following sintering at a high temperature, and also shock-wave compacted using explosives. The comparison of materials properties fabricated using different technologies at equal precursor powders parameters (dimensions

  56. Yuichi Otsuka, Masatoshi Imada

    We investigate the electronic structure of the transition-metal oxide YVO3 by a hybrid first-principles scheme. The density-functional theory with the local-density-approximation by using the local muffin-tin orbital basis is applied to derive the whole band structure. The electron degrees of freedom far from the Fermi level are eliminated by a downfolding p

  57. L. Petridis, E. M. Terentjev

    Nematic elastomers do not show the discontinuous, first-order, phase transition that the Landau-De Gennes mean field theory predicts for a quadrupolar ordering in 3D. We attribute this behavior to the presence of network crosslinks, which act as sources of quenched orientational disorder. We show that the addition of weak random anisotropy results in a singu

  58. Ali Nasir Imtani, V. K. Jindal

    Based on the helical and rotational symmetries and Tersoff-Brenner potential with couple of modified parameters, we investigate the variation of bond length/lengths in equilibrium structure due to tube length as well as due to applied hydrostatic pressure for a series of high symmetry armchair (n,n) single-wall nanotubes having different radii. Assuming that

  59. K. Ranjan, N. Kaurav, Dinesh Varshney, Keya Dharamvir

    Phonon dynamics of alkali metal atom, M doped in C60, forming MC60 solids in fcc phase has been studied. The calculations take into account Van-der-Waals and Coulomb interactions for M-C60 and C60-C60 and show fairly good agreement with reported neutron scattering results for RbC60. The calculations have also been done following Rigid Shell Model (RSM). We a

  60. Narinder Kaur, K. Dharamvir, V. K. Jindal

    We study the behavior of the C60 molecule under very high internal and external pressure using Tersoff potential. As a result, we calculate the critical internal and external pressures leading to its instability. We also calculate stretching force constant, breathing mode frequency and bulk modulus of this molecule. The data estimated here at zero pressure a

  61. K. Levin, Qijin Chen

    This article is written as a Lecture given in the 2006 Varenna Summer School on &#34;Ultracold Fermi Gases&#34;. Here we present a review of BCS--Bose Einstein condensation (BEC) crossover theory with emphasis on finite temperature effects. We discuss the role of temperature $T$ as it enters a theoretical formalism which is based on the standard BCS-Leggett

  62. T. Edagawa, Y. Fukumoto, A. Oguchi

    Using Tyablikov&#39;s decoupling approximation, we calculate the initial suppression rate of the Neel temperature, $R_{IS}=-lim_{x-> 0} T^{-1}_{N} dT_{N}/dx$, in a quasi two-dimensional diluted Heisenberg antiferromagnet with nonmagnetic impurities of concentration $x$. In order to explain an experimental fact that $R^{(Zn)}_{IS}=3.4$ of the Zn-substitution

  63. Ata Sarajedini, M. K. Barker, Doug Geisler, Paul Harding

    We present integrated photometry and color-magnitude diagrams (CMDs) for 24 star clusters in M33, of which 12 were previously uncataloged. These results are based on Advanced Camera for Surveys observations from the Hubble Space Telescope of two fields in M33. Our integrated V magnitudes and V-I colors for the previously identified objects are in good agreem

  64. Krzysztof Belczynski, Tomasz Bulik, Alexander Heger, Chris Fryer

    We study the evolution of first star (Population III) binaries. Under specific conditions, these stars may produce high redshift gamma-ray bursts (GRBs). We demonstrate that the occurrence rate of GRBs does not depend sensitively on evolutionary parameters in the population synthesis models. We show that the first binaries may form a very small group (< 1%)

  65. K. Werner, J. J. Drake, T. Rauch, S. Schuh

    We have performed soft X-ray spectroscopy of two hot white dwarfs with the Chandra observatory using the Low Energy Transmission Grating. The first target is the hot DA white dwarf LB1919 (Teff=69000 K). This star is representative of a small group of hot DAs whose metallicities lie well below predictions from radiative levitation theory. The Chandra spectru

  66. S. Vig, S. K. Ghosh, D. K. Ojha, R. P. Verma

    Aims: We have carried out an infrared study of the southern Galactic massive star forming region associated with IRAS 14416-5937. Methods: This star forming region has been mapped simultaneously in two far infrared bands at ~ 150 & 210 micron using the TIFR 1-m balloon borne telescope with ~ 1&#39; angular resolution. We have used 2MASS JHK$_s$ as well as Sp

  67. P. Saha, J. I. Read, L. L. R. Williams

    In the galaxy clusters SSDS J1004+411 and ACO 1689, a large number of multiply-imaged background objects have recently been observed. We use these data to map the projected mass distribution in the inner regions of these clusters. The source redshifts span a large range, which eliminates the degeneracies that plague nearly all lensing work. As a result the m

  68. K. Yoshida, R. Ohmori, T. Kobayashi, Y. Komori

    We have observed atmospheric gamma rays from 30GeV to 8TeV, using emulsion chambers at balloon altitudes, accumulating the largest total exposure in this energy range to date, SOT ~ 6.66m^2.sr.day. At very high altitudes, with residual overburden only a few g/cm^2, atmospheric gamma rays are mainly produced by a single interaction of primary cosmic rays with

  69. Nikolaos Diamantis, David Sim

    Explicit bases for the spaces of holomorphic cusp forms of all even positive weights and all orders are constructed. The dimensions of these spaces are computed.

  70. Mario A. Riquelme, David N. Spergel

    A new generation of CMB experiments will soon make sensitive high resolution maps of the microwave sky. At angular scales less than $\sim$10 arcminutes, most CMB anisotropies are generated at z $< 1000$, rather than at the surface of last scattering. Therefore, these maps potentially contain an enormous amount of information about the evolution of structure.

  71. Michael Cheng

    We present a calculation of the transition temperature for 3 flavor QCD using p4-improved staggered fermions with two different variants of fattened links. We examine various susceptibilities at two different values for the temporal extent - $N_t = 4$ and $N_t = 6$ - in the vicinity of the 3 flavor transition at vanishing chemical potential. For $N_t = 4$, w

  72. Brian C. Hall, William D. Kirwin

    Let M be a compact Kahler manifold equipped with a Hamiltonian action of a compact Lie group G. In this paper, we study the geometric quantization of the symplectic quotient M//G. Guillemin and Sternberg [Invent. Math. 67 (1982), 515--538] have shown, under suitable regularity assumptions, that there is a natural invertible map between the quantum Hilbert sp

  73. Mohammed Abouzaid

    Given a smooth projective toric variety X, we construct an A-infinity category of Lagrangians with boundary on a level set of the Landau-Ginzburg mirror of X. We prove that this category is quasi-equivalent to the DG category of line bundles on X. This establishes part of the Homological Mirror Conjecture for toric varieties.

  74. Sangwook Park, Koji Mori, Oleg Kargaltsev, Patrick O. Slane

    We report on the discovery of a pointlike source (CXOU J160103.1$-$513353) at the center of a Galactic supernova remnant (SNR) G330.2+1.0 with {\it Chandra X-Ray Observatory}. The X-ray spectrum fits a black-body (BB) model with $kT$ $\sim$ 0.49 keV, implying a small emission region of $R$ $\sim$ 0.4 km at the distance of 5 kpc. The estimated X-ray luminosit

  75. Stephan J. Huber, Maxim Pospelov, Adam Ritz

    We study the simplest generic extension of the Standard Model which allows for conventional electroweak baryogenesis, through the addition of dimension six operators in the Higgs sector. At least one such operator is required to be CP-odd, and we study the constraints on such a minimal setup, and related scenarios with minimal flavor violation, from the null

  76. Vitor Cardoso, Leonardo Gualtieri

    We study equilibrium shapes, stability and possible bifurcation diagrams of fluids in higher dimensions, held together by either surface tension or self-gravity. We consider the equilibrium shape and stability problem of self-gravitating spheroids, establishing the formalism to generalize the MacLaurin sequence to higher dimensions. We show that such simple

  77. Pierre Mathieu, David Ridout

    The Wess-Zumino-Witten model defined on the group SU(2) has a unique (non-trivial) simple current of conformal dimension k/4 for each level k. The extended algebra defined by this simple current is carefully constructed in terms of generalised commutation relations, and the corresponding representation theory is investigated. This extended algebra approach i

  78. Patrick Dorey, J. Luis Miramontes

    We propose an alternative understanding of the relationship between massive and massless magnonic TBA systems, using the T-duality symmetries of the Homogeneous sine-Gordon models. This is shown to be in agreement with a previous treatment by Dorey, Dunning and Tateo, based on the properties of Y-systems.

  79. Aaron Bergman

    I discuss the relation of Hochschild cohomology to the physical states in the closed topological string. This allows a notion of deformation intrinsic to the derived category. I use this to identify deformations of a quiver gauge theory associated to a D-branes at a singularity with generalized deformations of the geometry of the resolution of the singularit

  80. Jorge Ananias Neto

    We propose a variant scheme of the Gauge Unfixing formalism which modifies directly the original phase space variables of a constrained system. These new variables are gauge invariant quantities. We apply our procedure in a mixed constrained system that is the Abelian Pure Chern Simons Theory where several gains are obtained. In particular, from the gauge in

  81. Yoshiaki Koma, Miho Koma

    The spin-dependent corrections to the static inter-quark potential are phenomenologically relevant to describing the fine and hyperfine spin splitting of the heavy quarkonium spectra. We investigate these corrections, which are represented as the field strength correlators on the quark-antiquark source, in SU(3) lattice gauge theory. We use the Polyakov loop

  82. A. F. Ferrari, M. Gomes, J. R. Nascimento, E. Passos

    We study some physical consequences of the introduction of a Lorentz-violating modification term in the linearized gravity, which leads to modified dispersion relations for gravitational waves in the vacuum. We discuss two possible mechanisms for the induction of such a term in the Lagrangian. First, it is generated at the quantum level by a Lorentz-breaking

  83. Alvaro Pelayo

    We classify symplectic actions of 2-tori on compact, connected symplectic 4-manifolds, up to equivariant symplectomorphisms. This extends results of Atiyah, Guillemin-Sternberg, Delzant and Benoist. The classification is in terms of a collection of invariants, which are invariants of the topology of the manifold, of the torus action and of the symplectic for

  84. Christoph Kopper, Volkhard F. Müller

    In this paper we present an inductive renormalizability proof for massive $\vp_4^4$ theory on Riemannian manifolds, based on the Wegner-Wilson flow equations of the Wilson renormalization group, adapted to perturbation theory. The proof goes in hand with bounds on the perturbative Schwinger functions which imply tree decay between their position arguments. A

  85. Harry Buhrman, Matthias Christandl, Patrick Hayden, Hoi-Kwong Lo

    Unconditionally secure non-relativistic bit commitment is known to be impossible in both the classical and the quantum world. However, when committing to a string of n bits at once, how far can we stretch the quantum limits? In this letter, we introduce a framework of quantum schemes where Alice commits a string of n bits to Bob, in such a way that she can o

  86. Jose J. Ramasco, Bruno Goncalves

    Most real-world networks are weighted graphs with the weight of the edges reflecting the relative importance of the connections. In this work, we study non degree dependent correlations between edge weights, generalizing thus the correlations beyond the degree dependent case. We propose a simple method to introduce weight-weight correlations in topologically

  87. Sanjib Gupta, Edward F. Brown, Hendrik Schatz, Peter Moeller

    We perform a self-consistent calculation of the thermal structure in the crust of a superbursting neutron star. In particular, we follow the nucleosynthetic evolution of an accreted fluid element from its deposition into the atmosphere down to a depth where the electron Fermi energy is 20 MeV. We include temperature-dependent continuum electron capture rates

  88. L. Jiang, J. M. Taylor, M. D. Lukin

    Quantum repeaters create long-distance entanglement between quantum systems while overcoming difficulties such as the attenuation of single photons in a fiber. Recently, an implementation of a repeater protocol based on single qubits in atomic ensembles and linear optics has been proposed [Nature 414, 413 (2001)]. Motivated by rapid experimental progress tow

  89. Nicolas Boulanger, Serge Leclercq

    We solve the problem of constructing consistent first-order cross-interactions between spin-2 and spin-3 massless fields in flat spacetime of arbitrary dimension n > 3 and in such a way that the deformed gauge algebra is non-Abelian. No assumptions are made on the number of derivatives involved in the Lagrangian, except that it should be finite. Together wit

  90. Bing He, János A. Bergou, Zhiyong Wang

    We show that a general linear transformation from one single photon qudit to another, the dimension of which can be either equal or unequal to that of the first one, can be implemented by linear optics. As an application of the scheme we elaborate a method to deterministically realize any finite-element Positive Operator Value Measure (POVM) on single photon

  91. H. S. Nataraj, B. K. Sahoo, B. P. Das, R. K. Chaudhuri

    In this paper, we have carried out the calculations of the weighted oscillator strengths and the transition probabilities for a few low-lying transitions of boron-like ions: Mg VIII, Si X and S XII which are astrophysically important, particularly, in the atmospheres of the solar corona. We have employed an all-order relativistic many-body theory called the

  92. V. D&#39;Elia, F. Fiore, E. Meurs, G. Chincarini

    We analyze high resolution spectroscopic observations of the optical afterglow of GRB050730, obtained with UVES@VLT about hours after the GRB trigger. The spectrum shows that the ISM of the GRB host galaxy at z = 3.967 is complex, with at least five components contributing to the main absorption system. We detect strong CII*, SiII*, OI* and FeII* fine struct

  93. Georges Grunberg

    I show that Sudakov resummation takes a transparent form if one deals with the second logarithmic derivative of the short distance coefficient functions for deep inelastic scattering and the Drell-Yan process. A uniquely defined Sudakov exponent emerges, and the constant terms not included in the exponent are conjectured to be given by the second logarithmic

  94. M. D. Lumsden, S. E. Nagler, B. C. Sales, D. A. Tennant

    We have explored the magnetic excitation spectrum of the S=1/2 square lattice Heisenberg antiferromagnet, K2V3O8 using both triple-axis and time-of-flight inelastic neutron scattering. The long-wavelength spin waves are consistent with the previously determined Hamiltonian for this material. A small energy gap of 72+/-9 micro-eV is observed at the antiferrom

  95. Olga Lopez Acevedo, Jérémie Roland, Nicolas J. Cerf

    A quantum walk, \emph{i.e.}, the quantum evolution of a particle on a graph, is termed \emph{scalar} if the internal space of the moving particle (often called the coin) has a dimension one. Here, we study the existence of scalar quantum walks on Cayley graphs, which are built from the generators of a group. After deriving a necessary condition on these gene

  96. M. Roncarelli, S. Ettori, K. Dolag, L. Moscardini

    Using a set of hydrodynamical simulations of 9 galaxy clusters with masses in the range 1.5 10^{14} M_sun < M_vir < 3.4 10^{15} M_sun, we have studied the density, temperature and X-ray surface brightness profiles of the intracluster medium in the regions around the virial radius. We have analyzed the profiles in the radial range well above the cluster core,

  97. Luis Ferramacho, Alain Blanchard

    We investigate the cosmological test based on the evolution of the gas fraction in X-ray galaxy clusters and the stability of the cosmological parameters derived from it. Using a sample of distant clusters observed by XMM-Newton and Chandra, and comparing their gas fraction at different radii to the gas fraction observed for nearby clusters, we have determin

  98. J. Dias de Deus, P. Castelo Ferreira, J. Tito Mendonca

    A numerical estimative error of the magnitude of the vacuum polarization effect due to electron-positron by a factor of $10^3$ in [PRL97(2006)100403; 269901(E)] invalidates the study carried in this work in its present context.

  99. Ben Webster

    Let G be a reductive complex Lie group with Lie algebra g. We call a subgroup H of G {\bf cramped} if there is an integer b(G,H) such that each finite dimensional representation of G has a non-trivial invariant subspace of dimension less than b(G,H). We show that a subgroup is cramped if and only if the moment map from T^*(K/L) to k^* is surjective, where K

  100. Chris Clarkson, Mattias Marklund

    Quantum electrodynamics predicts that photons undergo one-loop scattering. The combined effect of this on the behaviour of a photon gas for temperatures above 10^{10} K results in a softening of the equation of state. We calculate the effect this has on the effective equation of state in the early universe, taking into account all the species of the Standard