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November 2007 arXiv papers — page 36

Showing 3,5013,600 of 5,016 papers

  1. P. Marecki

    We recall and generalize the analysis of the output of the so-called balanced homodyne detectors. The most important feature of these detectors is their ability to quantify the vacuum fluctuations of the electric field, that is expectation values of products of (quantum-) electric-field operators. More precisely, the output of BHDs provides information on th

  2. A. Amo, D. Sanvitto, D. Ballarini, F. P. Laussy

    Semiconductor microcavities offer a unique system to investigate the physics of weakly interacting bosons. Their elementary excitations, polaritons--a mixture of excitons and photons--behave, in the low density limit, as bosons that can undergo a phase transition to a regime characterised by long range coherence. Condensates of polaritons have been advocated

  3. Augustin Banyaga

    Using a "Hodge decomposition" of symplectic isotopies on a compact symplectic manifold $(M,ω)$, we construct a norm on the identity component in the group of all symplectic diffeomorphisms of $(M,ω)$ whose restriction to the group $Ham(M,ω)$ of hamiltonian diffeomorphisms is bounded from above by the Hofer norm. Moreover, $Ham(M,ω)$ is closed in $Sym

  4. Lukasz Andrzej Glinka

    Preliminaries for Many-Particle approach to quantization of Einstein-Hilbert theory of gravitation are presented in this paper. Einstein-Friedmann Spacetime is detailed discussed from this point of view. Von Neumann-Araki-Woods second quantization in Fock space of canonical Hamilton field equations is presented. In result Spacetime as system with Bose-Einste

  5. Dirk Schuricht

    We study the relation of Yangians and spinons in the SU(n) Haldane--Shastry model. The representation theory of the Yangian is shown to be intimately related to the fractional statistics of the spinons. We construct the spinon Hilbert space from tensor products of the fundamental representations of the Yangian.

  6. Steve Awodey, Nicola Gambino, Peter L. Lumsdaine, Michael A. Warren

    We present a solution to the problem of defining a counterpart in Algebraic Set Theory of the construction of internal sheaves in Topos Theory. Our approach is general in that we consider sheaves as determined by Lawvere-Tierney coverages, rather than by Grothendieck coverages, and assume only a weakening of the axioms for small maps originally introduced by

  7. Mauro Riccardi, Richard J. Szabo

    We re-examine various issues surrounding the definition of twisted quantum field theories on flat noncommutative spaces. We propose an interpretation based on nonlocal commutative field redefinitions which clarifies previously observed properties such as the formal equivalence of Green's functions in the noncommutative and commutative theories, causality

  8. P. Bozhilov

    We describe how Neumann and Neumann-Rosochatius type integrable systems, as well as the continuous limit of the SU(2) integrable spin chain, can be obtained from membranes on AdS_4 x S^7 background, in the framework of AdS/CFT correspondence.

  9. Daniel M. Kaplan

    Six-dimensional ionization cooling of muons is essential for muon colliders and possibly beneficial for neutrino factories. An experiment to demonstrate six-dimensional ionization cooling using practical apparatus is presented. It exploits recent innovative ideas that may lead to six-dimensional muon-cooling channels with emittance reduction approaching that

  10. Volkan Sevim, Per Arne Rikvold

    Robustness to mutations and noise has been shown to evolve through stabilizing selection for optimal phenotypes in model gene regulatory networks. The ability to evolve robust mutants is known to depend on the network architecture. How do the dynamical properties and state-space structures of networks with high and low robustness differ? Does selection opera

  11. Driss Essouabri

    In this paper I verify Manin's conjecture for a class of rational projective toric varieties with a large class of heights other than the usual one that comes from the standard metric on projective space.

  12. T. Lorenz, O. Heyer, M. Garst, F. Anfuso

    We present high-resolution measurements of the $c^\star$-axis thermal expansion and magnetostriction of piperidinium copper bromide \hp. The experimental data at low temperatures is well accounted for by a two-leg spin-ladder Hamiltonian. The thermal expansion shows a complex behaviour with various sign changes and approaches a $1/\sqrt{T}$ divergence at the

  13. H. Sotani, A. Colaiuda, K. D. Kokkotas

    We study the effect of the magnetic field geometry on the oscillation spectra of strongly magnetized stars. The magnetic field distributions include both toroidal and poloidal contributions. We observe that the toroidal contribution does not influence significantly the torsional oscillations of the crust. Moreover, in the case that the core is a type I super

  14. Emanuele Delucchi, Simona Settepanella

    Polar orderings arose in recent work of Salvetti and the second author on minimal CW-complexes for complexified hyperplane arrangements. We study the combinatorics of these orderings in the classical framework of oriented matroids, and reach thereby a weakening of the conditions required to actually determine such orderings. A class of arrangements for which

  15. Liljana Babinkostova

    We characterize the Hurewicz covering property in metrizable spaces in terms of properties of the metrics of the space. Then we show that a weak version of selective screenability, when combined with the Hurewicz property, implies selective screenability.

  16. Keely D. Snider, J. Jeff Hester, Steven J. Desch, Kevin R. Healy

    We present new Spitzer Space Telescope observations of the region NGC 2467, and use these observations to determine how the environment of an HII region affects the process of star formation. Our observations comprise IRAC (3.6, 4.5, 5.8, and 8.0 um) and MIPS (24 um) maps of the region, covering approximately 400 square arcminutes. The images show a region o

  17. J. Higes

    In this work we study two problems about Assouad-Nagata dimension: 1) Is there a metric space of non zero Assouad-Nagata dimension such that all of its asymptotic cones are of Assouad-Nagata dimension zero? (Dydak and Higes) 2) Suppose $G$ is a locally finite group with a proper left invariant metric $d_G$. If $\dim_{AN}(G, d_G)>0$, is $\dim_{AN} (G, d_G)$ i

  18. Tatsuru Kikuchi, Nobuchika Okada

    Once a parity is introduced in unparticle physics, under which unparticle provided in a hidden conformal sector is odd while all Standard Model particles are even, unparticle can be a suitable candidate for the cold dark matter (CDM) in the present universe through its coupling to the Standard Model Higgs doublet. We find that for Higgs boson mass in the ran

  19. R. Amanullah, V. Stanishev, A. Goobar, K. Schahmaneche

    We present multi-band light curves and distances for five type Ia supernovae at intermediate redshifts, 0.18<z<0.27. Three telescopes on the Canary Island of La Palma, INT, NOT and JKT, were used for discovery and follow-up of type Ia supernovae in the g&#39; and r&#39; filters. Supernova fluxes were measured by simultaneously fitting a supernova and host ga

  20. L. Naso, L. Rezzolla, A. Bonanno, L. Paternò

    During the first 40 s after their birth, proto-neutron stars are expected to be subject to at least two types of instability: the convective instability and the neutron-finger one. Both instabilities involve convective motions and hence can trigger dynamo actions which may be responsible for the large magnetic fields in neutron stars and magnetars. We have s

  21. Jacob Lund Fisker, Robert D. Hoffman, Jason Pruet

    We discuss implications of recent precision measurements for the Rh93 proton separation energy for the production of the lightest molybdenum isotopes in proton-rich type II supernova ejecta. It has recently been shown that a novel neutrino-induced process makes these ejecta a promising site for the production of the light molybdenum isotopes and other &#34;p

  22. V. A. Kuz&#39;menko

    Physical nature of widely known Ramsey fringes phenomenon is discussed.

  23. J. -C. Domenge, C. Lhuillier, L. Messio, L. Pierre

    The phase diagram of the classical \jj model on the \kag lattice is investigated using extensive \mc simulations. In a realistic range of parameters, this model has a low-temperature chiral-ordered phase without long-range spin order. We show that the critical transition marking the destruction of chiral order is preempted by the first order proliferation of

  24. Marco Pettini

    This submission has been withdrawn by arXiv administrators because it is incomplete and thus violates arXiv policy.

  25. Michele Bolognesi, Gian Pietro Pirola

    This paper deals with some classical problems about the projective geometry of complex algebraic curves. We call \textit{locally toric} a projective curve that in a neighbourhood of every point has a local analytical parametrization of type $(t^{a_1},...,t^{a_n})$, with $a_1,..., a_n$ relatively prime positive integers. In this paper we prove that the genera

  26. B. Alles, A. Papa

    By analytic continuation to real theta of data obtained from numerical simulation at imaginary theta we study the Haldane conjecture and show that the O(3) non-linear sigma model with a theta term in 2 dimensions becomes massless at theta=3.10(5). A modified cluster algorithm has been introduced to simulate the model with imaginary theta. Two different defin

  27. William B. Sparks, Howard E. Bond, Misty Cracraft, Zolt Levay

    Following the outburst of the unusual variable star V838 Monocerotis in 2002, a spectacular light echo appeared. A light echo provides the possibility of direct geometric distance determination, because it should contain a ring of highly linearly polarized light at a linear radius of ct, where t is the time since the outburst. We present imaging polarimetry

  28. Susan J. Sierra

    We consider the first Weyl algebra, A, in the Euler gradation, and completely classify graded rings B that are graded equivalent to A: that is, the categories gr-A and gr-B are equivalent. This includes some surprising examples: in particular, we show that A is graded equivalent to an idealizer in a localization of A. We obtain this classification as an appl

  29. Sugata Kaviraj, Sebastien Peirani, Sadegh Khochfar, Joseph Silk

    We demonstrate that the large scatter in the ultra-violet (UV) colours of intermediate-mass early-type galaxies in the local Universe and the inferred low-level recent star formation in these objects can be reproduced by minor mergers in the standard LCDM cosmology. Numerical simulations of mergers with mass ratios less than or equal to 1:4, with reasonable

  30. D. Schmeltzer

    We report the first calculation of persistent current in two coupled rings which form a character ``8&#39;&#39; genus g=2 structure. We obtain an exact solution for the persistent current and investigated the exact solution numerically. For two large coupled rings with equal fluxes, we find that the persistent current in the two coupled rings is equal to tha

  31. Gui-Jun Ding

    The difference between Z(4430) as a $D^{*}D_1$ molecule and a tetraquark state and how to distinguish between them are discussed. We construct an effective Lagrangian with $D^{*}D_1$ contact interactions constrained by the heavy quark symmetry and chiral symmetry to study Z(4430). We find that if Z(4430) is a $D^{*}D_1$ molecule state, there should be a $B^{

  32. T. Keilmann, J. J. Garcia-Ripoll

    We propose a scheme to create a metastable state of paired bosonic atoms in an optical lattice. The most salient features of this state are that the wavefunction of each pair is a Bell state and that the pair size spans half the lattice, similar to fermionic Cooper pairs. This mesoscopic state can be created with a dynamical process that involves crossing a

  33. Stefano Galatolo, Mathieu Hoyrup, Cristobal Rojas

    In the general context of computable metric spaces and computable measures we prove a kind of constructive Borel-Cantelli lemma: given a sequence (constructive in some way) of sets $A_{i}$ with effectively summable measures, there are computable points which are not contained in infinitely many $A_{i}$. As a consequence of this we obtain the existence of com

  34. Sabine Jansen, Elliott H. Lieb, Ruedi Seiler

    We investigate Laughlin&#39;s fractional quantum Hall effect wave function on a cylinder. We show that it displays translational symmetry breaking in the axial direction for sufficiently thin cylinders. At filling factor 1/p, the period is p times the period of the filled lowest Landau level. The proof uses a connection with one-dimensional polymer systems a

  35. Krishna R. Narayanan, Arun R. Srinivasa

    The concept of temperature is one of the key ideas in describing the thermodynamical properties of a physical system. In classical statistical mechanics of ideal gases, the notion of temperature can be described in two different ways, the kinetic temperature and the thermodynamic temperature. For the Boltzmann distribution, the two notions lead to the same r

  36. Michael Taylor, Jose Manuel Vilchez

    This draft (in preparation) has been withdrawn so as to be combined with its second part (work also in preparation), to produce a single paper, that includes further analysis and revisions done after new important results obtained.

  37. Karl Svozil

    Unlike classical information, quantum knowledge is restricted to the outcome of measurements of maximal observables corresponding to single contexts.

  38. Avraham Aizenbud, Dmitry Gourevitch, Eitan Sayag

    Let V be a quadratic space with a form q over an arbitrary local field F of characteristic different from 2. Let $W=V \oplus Fe$ with the form Q extending q with Q(e)=1. Consider the standard embedding of O(V) into O(W) and the two-sided action of $O(V)\times O(V)$ on $O(W)$. In this note we show that any $O(V)\times O(V)$-invariant distribution on O(W) is i

  39. J. Alvarez-Muniz, R. Conceicao, J. Dias de Deus, M. C. Espirito Santo

    It is well known that, in nuclear collisions, a sizable fraction of the available energy is carried away by baryons. As the baryon number is conserved, the net-baryon $B-\bar{B}$ retains information on the energy-momentum carried by the incoming nuclei. A simple but consistent model for net-baryon production in high energy hadron-hadron, hadron-nucleus and n

  40. Yoshiharu Maeno, Yukio Ohsawa

    An empty spot refers to an empty hard-to-fill space which can be found in the records of the social interaction, and is the clue to the persons in the underlying social network who do not appear in the records. This contribution addresses a problem to predict relevant empty spots in social interaction. Homogeneous and inhomogeneous networks are studied as a

  41. Q. He, for CLEO Collaboration

    We present measurements of D -> K0_S pi and D -> K0_L pi branching fractions using 281 pb-1 of psi(3770) data at the CLEO-c experiment. We find that B(D0 -> K0_S pi0) is larger than B(D0 -> K0_L pi0), with an asymmetry of R(D0) = 0.108 +- 0.025 +- 0.024. For B(D+ -> K0_S pi+) and B(D+ -> K0_L pi+), we observe no measurable difference; the asymmetry is R(D+)

  42. Tao Ma, Shu-Min Li

    We prove the multi-band Bloch oscillation and Stark ladder in the $nk$ and site representation from the Floquet theorem. The proof is also possible from the equivalence between the Floquet system, Bloch oscillation, and the rotator with spin. We also exactly solve the periodically driven two level atom and two band Bloch oscillation in terms of Heun function

  43. Sanjib Kumar Agarwalla, Sandhya Choubey, Amitava Raychaudhuri

    We expound in detail the physics reach of an experimental set-up in which the proposed large magnetized iron detector at the India-based Neutrino Observatory (INO) would serve as the far detector for a so-called beta-beam. If this pure $\nue$ and/or $\anue$ beam is shot from some source location like CERN such that the source-detector distance $L \simeq 7500

  44. Karin Baur, Bethany Marsh

    We construct frieze patterns of type D_N with entries which are numbers of matchings between vertices and triangles of corresponding triangulations of a punctured disc. For triangulations corresponding to orientations of the Dynkin diagram of type D_N, we show that the numbers in the pattern can be interpreted as specialisations of cluster variables in the c

  45. Axel Maas, Stefan Olejnik

    G_2 Yang--Mills theory is an interesting laboratory to investigate non-perturbative effects. On one hand, no conventional quark confinement via a linearly rising potential is present. On the other hand, its thermodynamic properties are similar to ordinary SU(N) Yang--Mills theory. Finally, it has been conjectured that gluons are removed from the physical spe

  46. Christian G. Boehmer, Gyula Fodor

    We examine static perfect fluid spheres in the presence of a cosmological constant. New exact matter solutions are discussed which require the Nariai metric in the vacuum region. We generalize the Einstein static universe such that neither its energy density nor its pressure is constant throughout the spacetime. Using analytical techniques we derive conditio

  47. Emil Prodan

    We consider single particle Schrodinger operators with a gap in the en ergy spectrum. We construct a complete, orthonormal basis function set for the inv ariant space corresponding to the spectrum below the spectral gap, which are exponentially localized a round a set of closed surfaces of monotonically increasing sizes. Estimates on the exponential dec ay r

  48. Shinichi Deguchi, Satoshi Hayakawa

    The 4-dimensional model with topological mass generation that has recently been presented by Dvali, Jackiw and Pi [G. Dvali, R. Jackiw, and S.-Y. Pi, Phys. Rev. Lett. 96, 081602 (2006), hep-th/0610228] is generalized to any even number of dimensions. As in the 4-dimensional model, the 2n-dimensional model describes a mass-generation phenomenon due to the pre

  49. Fabio Fontanot, Rachel S. Somerville, Sebastian Jester

    The QSO luminosity function at z>5 provides strong constraints on models of joint evolution of QSO and their hosts. However, these observations are challenging because the low space densities of these objects necessitate surveying of large areas, in order to obtain statistically meaningful samples, while at the same time cosmological redshifting and dimming

  50. Roumen Tsekov

    A nonlinear theory of quantum Brownian motion in classical environment is developed based on a thermodynamically enhanced nonlinear Schrodinger equation. The latter is transformed via the Madelung transformation into a nonlinear quantum Smoluchowski-like equation, which is proven to reproduce key results from quantum and classical physics. The application of

  51. Christophe Real

    In the present article, which is the first part of a work in three parts, we build an equation of quantum gravity. This equation is tensorial, is equivalent to general relativity in vacuum, but differs completely from general relativity inside matter. This new equation possesses a dimensionless gravitational coupling constant, and passes all experimental tes

  52. Stefan Geiss, Anni Toivola

    We consider weak convergence of the rescaled error processes arising from Riemann discretizations of certain stochastic integrals and relate the $L_p$-integrability of the weak limit to the fractional smoothness in the Malliavin sense of the stochastic integral.

  53. K. -F. Berggren, D. N. Maksimov, A. F. Sadreev, R. Hoehmann

    This article reports on a joint theoretical and experimental study of the Pauli quantum-mechanical stress tensor $T_{αβ}(x,y)$ for open two-dimensional chaotic billiards. In the case of a finite current flow through the system the interior wave function is expressed as $ψ= u+iv$. With the assumption that $u$ and $v$ are Gaussian random fields we derive analy

  54. Grigorii Melnichenko

    In the paper, we show that quantum logic of linear subspaces can be used for recognition of random signals by a Bayesian energy discriminant classifier. The energy distribution on linear subspaces is described by the correlation matrix of the probability distribution. We show that the correlation matrix corresponds to von Neumann density matrix in quantum th

  55. Lotfi Ben-Jaffel

    Many extrasolar planets orbit closely to their parent star. Their existence raises the fundamental problem of loss and gain in their mass. For exoplanet HD209458b, reports on an unusually extended hydrogen corona and a hot layer in the lower atmosphere seem to support the scenario of atmospheric inflation by the strong stellar irradiation. However, difficult

  56. Inaki Garcia-Etxebarria, Angel M. Uranga

    We discuss the behaviour of non-perturbative superpotentials in 4d N=1 type II compactifications (and orientifolds thereof) near lines of marginal stability, where the spectrum of contributing BPS D-brane instantons changes discontinuously. The superpotential is nevertheless continuous, in agreement with its holomorphic dependence on the closed string moduli

  57. Kwan-hang Lam

    We consider noncompact complete manifolds with Spin(9) holonomy and proved an one end result and a splitting type theorem under different conditions on the bottom of the spectrum. We proved that any harmonic functions with finite Dirichlet integral must be Cayley-harmonic, which allowed us to conclude an one end result. In the second part, we established a s

  58. Santos Bravo Yuste, J. Klafter, Katja Lindenberg

    The asymptotic mean number of distinct sites visited by a subdiffusive continuous time random walker in two dimensions seems not to have been explicitly calculated anywhere in the literature. This number has been calculated for other dimensions for only one specific asymptotic behavior of the waiting time distribution between steps. We present an explicit de

  59. Michio Otsuki, Hisao Hayakawa

    The long-time behaviors of the velocity autocorrelation function $C(t)$ for sheared fluids ^M are investigated theoretically and numerically. It is found the existence of the cross-overs of^M $C(t)$ from $t^{-d/2}$ to $t^{-d}$ ^M in sheared fluids of elastic particles without any thermostat, and from $t^{-d/2}$ to $t^{-(d+2)/2}$ ^M in both sheared fluids of

  60. J. Morin, J. -F. Donati, T. Forveille, X. Delfosse

    We report in this paper phase-resolved spectropolarimetric observations of the rapidly-rotating fully-convective M4 dwarf V374 Peg, on which a strong, mainly axisymmetric, large-scale poloidal magnetic field was recently detected. In addition to the original data set secured in 2005 August, we present here new data collected in 2005 September and 2006 August

  61. Hai-Yang Cheng

    Charmless 3-body decays of $B$ mesons are studied using a simple model based on the framework of the factorization approach. We have identified a large source of the nonresonant signal in the matrix elements of scalar densities, e.g. $<K\bar K|\bar ss|0>$. This explains the dominance of the nonresonant background in $B\to KKK$ decays, the sizable nonresonant

  62. G. A. Diamandis, B. C. Georgalas, P. Kouroumalou, A. B. Lahanas

    We discuss the on-shell N=1 Supersymmetric coupling of brane chiral multiplets in the context of N=2, D=5 Supergravity compactified on $S_1/Z_2$ orbifolds. Assuming a constant superpotential on the hidden brane we study the transmission of the supersymmetry breaking to the visible brane. We find that to lowest order in the five dimensional Newton&#39;s const

  63. Boris Kolev

    This paper investigates different Poisson structures that have been proposed to give a Hamiltonian formulation to evolution equations issued from fluid mechanics. Our aim is to explore the main brackets which have been proposed and to discuss the difficulties which arise when one tries to give a rigorous meaning to these brackets. Our main interest is in the

  64. Xingang Wang, Shuguang Guan, Ying-Cheng Lai, Choy Heng Lai

    By a model of coupled phase oscillators, we show analytically how synchronization in {\em non-identical} complex networks can be enhanced by introducing a proper gradient into the couplings. It is found that, by pointing the gradient from the large-degree to the small-degree nodes on each link, increasing the gradient strength will bring forward the {\em ons

  65. Emma Y. Jin, Christian M. Reidys

    In this paper we enumerate $k$-noncrossing RNA pseudoknot structures with given minimum stack-length. We show that the numbers of $k$-noncrossing structures without isolated base pairs are significantly smaller than the number of all $k$-noncrossing structures. In particular we prove that the number of 3- and 4-noncrossing RNA structures with stack-length $\

  66. Hendryk Pfeiffer

    We show that every modular category is equivalent as an additive ribbon category to the category of finite-dimensional comodules of a Weak Hopf Algebra. This Weak Hopf Algebra is finite-dimensional, split cosemisimple, weakly cofactorizable, coribbon and has trivially intersecting base algebras. In order to arrive at this characterization of modular categori

  67. Keki Burjorjee

    The pace of progress in the fields of Evolutionary Computation and Machine Learning is currently limited -- in the former field, by the improbability of making advantageous extensions to evolutionary algorithms when their capacity for adaptation is poorly understood, and in the latter by the difficulty of finding effective semi-principled reductions of hard

  68. Alexander F. Ritter

    Let L be an exact Lagrangian submanifold inside the cotangent bundle of a closed manifold N. We prove that if N satisfies a mild homotopy assumption then the image of π_2(L) in π_2(N) has finite index. We make no assumption on the Maslov class of L, and we make no orientability assumptions. The homotopy assumption is either that N is simply connected, or mor

  69. Tsutomu Kobayashi, Masato Nozawa, Yu-ichi Takamizu

    We study the emission of scalar fields into the bulk from a six-dimensional rotating black hole pierced by a 3-brane. We determine the angular eigenvalues in the presence of finite brane tension by using the continued fraction method. The radial equation is integrated numerically, giving the absorption probability (graybody factor) in a wider frequency range

  70. S. Y. Choi

    Two next-generation high-energy experiments, the Large Hadron Collider (LHC) and the $e^+e^-$ International Linear Collider (ILC), are highly expected to unravel the new structure of matter and forces from the electroweak scale to the TeV scale. In this talk we give a compelling but rather descriptive review of the complementary role of LHC and ILC in drawin

  71. L. -S. Bouchard, A. O. Sushkov, D. Budker, J. J. Ford

    Motivated by a recent proposal by O. P. Sushkov and co-workers to search for a P,T-violating Schiff moment of the $^{207}$Pb nucleus in a ferroelectric solid, we have carried out a high-field nuclear magnetic resonance study of the longitudinal and transverse spin relaxation of the lead nuclei from room temperature down to 10 K for powder samples of lead tit

  72. J. L. Musfeldt, S. Brown, S. Mazumdar, R. T. Clay

    We measured the variable temperature infrared response of the spin ladder candidate (DTTTF)2Cu(mnt)2 in order to distinguish between two competing ladder models, rectangular versus zigzag, proposed for this family of materials. The distortion along the stack direction below 235 K is consistent with a doubling along b through the metal-insulator transition. W

  73. Andrew P. Hines, P. C. E. Stamp

    Decoherence is the major stumbling block in the realization of a large-scale quantum computer. Ingenious methods have been devised to overcome decoherence, but their success has been proven only for over-simplified models of system-environment interaction. Whether such methods will be reliable in the face of more realistic models is a fundamental open questi

  74. Jeff Cooke

    Type IIn supernovae (SNe IIn) dominate the brightest supernova events in observed FUV flux (~1200-2000A). We show that multi-band, multi-epoch optical surveys complete to m_r = 27 can detect the FUV emission of ~25 z > 2 SNe IIn deg^-2 yr^-1 rest-frame (~10 SNe IIn deg^-2 yr^-1 observed-frame) to 4 sigma using a technique monitoring color-selected galaxies.

  75. D. S. L. Figueira, N. C. Frateschi

    Microdisks and microstadium resonators were fabricated on erbium doped amorphous hydrogenated silicon (a-Si:H<Er>) layers sandwiched in air and native SiO2 on Si substrates. Annealing condition is optimized to allow large emission at 1550 nm for samples with erbium concentrations as high as 1.02x10^20 atoms/cm3. Near field scanning optical microscopy shows e

  76. C. Denson Hill, Mauro Nacinovich

    We discuss the maximum modulus principle, and weak unique continuation, for CR functions on an abstract almost CR manifold M. We investigate these matters under the assumption of weak pseudoconcavity, and obtain sharp results about propagation along Sussmann leaves.

  77. W. Zhang, M. A. Zudov, L. N. Pfeiffer, K. W. West

    Using dc excitation to spatially tilt Landau levels, we study resonant acoustic phonon scattering in two-dimensional electron systems. We observe that dc electric field strongly modifies phonon resonances, transforming resistance maxima into minima and back into maxima. Further, phonon resonances are enhanced dramatically in the non-linear dc response and ca

  78. Nathan Jones

    Given a non-CM elliptic curve E over Q, define the ``torsion conductor&#39;&#39; m_E to be the smallest positive integer so that the Galois representation on the torsion of E has image Pi^{-1}(Gal(Q(E[m_E])/Q), where Pi denotes the natural projection GL_2(\hat{Z}) onto GL_2(Z/m_E Z). We show that, uniformly for semi-stable non-CM elliptic curves E over Q, m_

  79. Kalanand Mishra

    We report recent results of the Dalitz plot analyses of D and D_S decays performed by the BaBar collaboration, and point out some of the important applications of these results.

  80. S. K. Bose

    We present a study of the electronic structure, phonon frequencies and electron-phonon coupling in hcp Sc under pressure. The electron-phonon coupling constant is found to increase steadily with pressure in the hcp phase, until the pressure reaches a value where the hcp phase becomes unstable. Calculations for the normal pressure $c/a$ ratio predict a phase

  81. Yang Qi, Subir Sachdev

    Mott insulators with a half-filled band of electrons on the triangular lattice have been recently studied in a variety of organic compounds. All of these compounds undergo transitions to metallic/superconducting states under moderate hydrostatic pressure. We describe the Mott insulator using its hypothetical proximity to a Z_2 spin liquid of bosonic spinons.

  82. Stuart L. Shapiro

    Black holes are popping up all over the place: in compact binary X-ray sources and GRBs, in quasars, AGNs and the cores of all bulge galaxies, in binary black holes and binary black hole-neutron stars, and maybe even in the LHC! Black holes are strong-field objects governed by Einstein&#39;s equations of general relativity. Hence general relativistic, numeri

  83. John Martino, Stewart Priddy

    The group ring of the automorphism group of a p-group is studied using the automorphism groups of subgroups and quotient groups of P.

  84. Friedrich W. Hehl, Yuri N. Obukhov

    We review the application of torsion in field theory. First we show how the notion of torsion emerges in differential geometry. In the context of a Cartan circuit, torsion is related to translations similar as curvature to rotations. Cartan&#39;s investigations started by analyzing Einsteins general relativity theory and by taking recourse to the theory of C

  85. Tim Berners-Lee, Dan Connolly, Lalana Kagal, Yosi Scharf

    The Semantic Web drives towards the use of the Web for interacting with logically interconnected data. Through knowledge models such as Resource Description Framework (RDF), the Semantic Web provides a unifying representation of richly structured data. Adding logic to the Web implies the use of rules to make inferences, choose courses of action, and answer q

  86. Helmut G. Katzgraber

    Spin glasses are paradigmatic models that deliver concepts relevant for a variety of systems. However, rigorous analytical results are difficult to obtain for spin-glass models, in particular for realistic short-range models. Therefore large-scale numerical simulations are the tool of choice. Concepts and algorithms derived from the study of spin glasses hav

  87. Edward F. Guinan, Scott G. Engle

    The evolution over time of the magnetic activity and the resulting X-ray and UV coronal and chromospheric emissions of main-sequence dG, dK, and dM stars with widely different ages are discussed. Young cool stars spin rapidly and have correspondingly very robust magnetic dynamos and strong coronal and chromospheric X-ray - UV (XUV) emissions. However, these

  88. Chao Jiang, S. G. Srinivasan, A. Caro, S. A. Maloy

    Using first-principles calculations within the generalized gradient approximation, we predicted the lattice parameters, elastic constants, vibrational properties, and electronic structure of cementite (Fe3C). Its nine single-crystal elastic constants were obtained by computing total energies or stresses as a function of applied strain. Furthermore, six of th

  89. Federico Corberi, Andrea Gambassi, Eugenio Lippiello, Marco Zannetti

    Motivated by recent numerical findings [M. Henkel, T. Enss, and M. Pleimling, J. Phys. A: Math. Gen. 39 (2006) L589] we re-examine via Monte Carlo simulations the linear response function of the two-dimensional Ising model with Glauber dynamics quenched to the critical point. At variance with the results of Henkel et al., we detect discrepancies between the

  90. Adela Kawka, Stephane Vennes, Jean Dupuis, Pierre Chayer

    We present FUSE observations of the hot white dwarfs in the post-common envelope binaries Feige 24, EUVE J0720-317, BPM 6502, and EUVE J2013+400. The spectra show numerous photospheric absorption lines which trace the white dwarf orbital motion. We report the detection of C III, O VI, P V, and Si IV in the spectra of Feige 24, EUVE J0720-317 and EUVE J2013+4

  91. R. Lopez, S. F. Sanchez, B. Garcia-Lorenzo, R. Estalella

    We present new results on the nature of the Herbig-Haro-like object 73 (HHL73, also known as [G84b] 11) based on narrow-band CCD H_alpha and [SII] images of the HHL73 field, and Integral Field Spectroscopy and radio continuum observations at 3.6 cm covering the emission of the HHL 73 object. The CCD images allow us to resolve the HHL 73 comet-shaped morpholo

  92. R. H. D. Corbet, J. L. Sokoloski, K. Mukai, C. B. Markwardt

    We present an analysis of the X-ray variability of three symbiotic X-ray binaries, GX 1+4, 4U 1700+24, and 4U 1954+31, using observations made with the Swift Burst Alert Telescope (BAT) and the Rossi X-ray Timing Explorer (RXTE) All-Sky Monitor (ASM). Observations of 4U 1954+31 with the Swift BAT show modulation at a period near 5 hours. Models to explain th

  93. R. Jackiw

    The functional integral has many triumphs in elucidating quantum theory. But incorporating charge fractionalization into that formalism remains a challenge.

  94. Daniel Braun, Bertrand Georgeot

    We study the influence of errors and decoherence on both the performance of Shor&#39;s factoring algorithm and Grover&#39;s search algorithm, and on the amount of interference in these algorithms using a recently proposed interference measure. We consider systematic unitary errors, random unitary errors, and decoherence processes. We show that unitary errors

  95. Mark Dierckxsens

    Sensitivities to neutrino oscillation parameters for possible very long baseline neutrino oscillation experiments are discussed. The reach for observing a non-zero mixing angle $θ_{13}$, establishing CP violation and determining the mass hierarchy are compared between various experimental options. Different possibilities for neutrino beams are briefly descri

  96. A. Bondar, A. Poluektov

    This report shows the latest results on the study of the method to determine the angle phi_3 of the unitarity triangle using Dalitz plot analysis of $D^0$ decay from B->DK process in a model-independent way. We concentrate on the case with a limited charm data sample, which will be available from the CLEO-c collaboration in the nearest future, with the main

  97. Saverio Russo, Jeroen B. Oostinga, Dominique Wehenkel, Hubert B. Heersche

    We investigate experimentally transport through ring-shaped devices etched in graphene and observe clear Aharonov-Bohm conductance oscillations. The temperature dependence of the oscillation amplitude indicates that below 1 K the phase coherence length is comparable to or larger than the size of the ring. An increase in the amplitude is observed at high magn

  98. K. Tsekouras, A. B. Kolomeisky

    Asymmetric exclusion processes for particles moving on parallel channels with inhomogeneous coupling are investigated theoretically. Particles interact with hard-core exclusion and move in the same direction on both lattices, while transitions between the channels is allowed at one specific location in the bulk of the system. An approximate theoretical appro

  99. Gerald Moore

    We construct an algorithm for approximating the invariant tori created at a Neimark-Sacker bifurcation point. It is based on the same philosophy as many algorithms for approximating the periodic orbits created at a Hopf bifurcation point, i.e. a Fourier spectral method. For Neimark-Sacker bifurcation, however, we use a simple parametrisation of the tori in o

  100. Tanmoy Das, R. S. Markiewicz, A. Bansil

    We discuss evolution of the Fermi surface (FS) topology with doping in electron doped cuprates within the framework of a one-band Hubbard Hamiltonian, where antiferromagnetism and superconductivity are assumed to coexist in a uniform phase. In the lightly doped insulator, the FS consists of electron pockets around the $(π,0)$ points. The first change in the