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February 2009 arXiv papers — page 35

Showing 3,4013,500 of 4,929 papers

  1. Hakim Boumaza

    We study localization properties for a class of one-dimensional, matrix-valued, continuous, random Schr\"odinger operators, acting on $L^2(\R)\otimes \C^N$, for arbitrary $N\geq 1$. We prove that, under suitable assumptions on the F\"urstenberg group of these operators, valid on an interval $I\subset \R$, they exhibit localization properties on $I$, both in

  2. O Derzhko, J Richter, A Honecker

    We consider the antiferromagnetic Heisenberg model and the repulsive Hubbard model for a class of frustrated lattices with a completely dispersionless (flat) lowest one-particle (either one-magnon or one-electron) band. We construct exact many-particle ground states for a wide range of particle densities, calculate their degeneracy, and, as a result, obtain

  3. Robert O. Bauer

    We give a direct construction of the conformally invariant measure on self-avoiding loops in Riemann surfaces (Werner measure) from chordal $\text{SLE}_{8/3}$. We give a new proof of uniqueness of the measure and use Schramm's formula to construct a measure on boundary bubbles encircling an interior point. After establishing covariance properties for thi

  4. T. P. Polak, T. K. Kopec

    We study the superfluid to Mott-insulator transition of bosons in an optical anizotropic lattice by employing the Bose-Hubbard model living on a two-dimensional lattice with anizotropy parameter $κ$. The compressible superfluid state and incompressible Mott-insulator (MI) lobes are efficiently described analytically, using the quantum U(1) rotor approach. Th

  5. Álvaro Villalobos, Amina Helmi

    We analyse the phase-space structure of simulated thick discs that are the result of a significant merger between a disc galaxy and a satellite. Our main goal is to establish what would be the characteristic imprints of a merger origin for the Galactic thick disc. We find that the spatial distribution predicted for thick disc stars is asymmetric, seemingly i

  6. Satyabrata Adhikari

    Quantum mechanics put restriction on performing some task which we can do classically. One such restriction is that we cannot copy an arbitrary quantum state. This is known as No-cloning theorem. Although quantum mechanics forbid us to construct a perfect cloner, there is no restriction to construct an imperfect cloner. Therefore, we have constructed and stu

  7. Peichun Tsai, Alisia M. Peters, Christophe Pirat, Matthias Wessling

    We employ micro-particle image velocimetry ($μ$-PIV) to investigate laminar micro-flows in hydrophobic microstructured channels, in particular the slip length. These microchannels consist of longitudinal micro-grooves, which can trap air and prompt a shear-free boundary condition and thus slippage enhancement. Our measurements reveal an increase of the slip

  8. Hua-Lin Huang

    We provide a quiver setting for quasi-Hopf algebras, generalizing the Hopf quiver theory. As applications we obtain some general structure theorems, in particular the quasi-Hopf analogue of the Cartier theorem and the Cartier-Gabriel decomposition theorem.

  9. R. A. Battye, I. W. A. Browne, N. Jackson

    We have examined the statistics of the polarization position angles determined for point sources in the NRAO-VLA sky survey (NVSS) and find that there is a statistically significant bias toward angles which are multiples of 45 degrees. The formal probability that the polarization angles are drawn from a uniform distribution is exponentially small. When the s

  10. T. Adachi, H. Sato, M. Fujita, K. Yamada

    We have measured the temperature dependences of Rho and Chi for Fe-substituted La_2-x_Sr_x_Cu_1-y_Fe_y_O_4_ in the overdoped regime, in order to investigate Fe-substitution effects on electronic properties around x=0.22. From the Rho measurements, it has been found around x=0.22 that the values of Rho are large at room temperature and that Rho exhibits a pro

  11. Junyang Yu

    We consider several distances between two sets of points, which are modifications of the Hausdorff metric, and apply them to describe some fractals such as $δ$-quasi-self-similar sets, and some other geometric notions in Euclidean space, such as tilings with quasi-prototiles and patterns with quasi-motifs. For the $δ$-quasi-self-similar sets satisfying the o

  12. C. Martin-Zaidi, E. Habart, J. -C. Augereau, F. Ménard

    We present high-resolution spectroscopic mid-infrared observations of the circumstellar disk around the Herbig Ae star HD97048 obtained with the VLT Imager and Spectrometer for the mid-InfraRed (VISIR). We conducted observations of mid-infrared pure rotational lines of molecular hydrogen (H2) as a tracer of warm gas in the disk surface layers. In a previous

  13. Mohab Safey El Din, Éric Schost

    We consider the problem of constructing roadmaps of real algebraic sets. The problem was introduced by Canny to answer connectivity questions and solve motion planning problems. Given $s$ polynomial equations with rational coefficients, of degree $D$ in $n$ variables, Canny's algorithm has a Monte Carlo cost of $s^n\log(s) D^{O(n^2)}$ operations in $\mat

  14. Arjun Berera, David Hochberg

    The Galilean invariance of the Navier-Stokes equation is shown to be akin to a global gauge symmetry familiar from quantum field theory. This symmetry leads to a multiple counting of infinitely many inertial reference frames in the path integral approach to randomly stirred fluids. This problem is solved by fixing the gauge, i.e., singling out one reference

  15. Roberto Di Cosmo, Stefano Zacchiroli, Paulo Trezentos

    The upgrade problems faced by Free and Open Source Software distributions have characteristics not easily found elsewhere. We describe the structure of packages and their role in the upgrade process. We show that state of the art package managers have shortcomings inhibiting their ability to cope with frequent upgrade failures. We survey current countermeasu

  16. André Gronemeier

    Here we prove an asymptotically optimal lower bound on the information complexity of the k-party disjointness function with the unique intersection promise, an important special case of the well known disjointness problem, and the ANDk-function in the number in the hand model. Our (n/k) bound for disjointness improves on an earlier (n/(k log k)) bound by Cha

  17. Veselin Jungic, Tomas Kaiser, Daniel Kral

    We study the mixed Ramsey number maxR(n,K_m,K_r), defined as the maximum number of colours in an edge-colouring of the complete graph K_n, such that K_n has no monochromatic complete subgraph on m vertices and no rainbow complete subgraph on r vertices. Improving an upper bound of Axenovich and Iverson, we show that maxR(n,K_m,K_4) <= n^{3/2}\sqrt{2m} for al

  18. Ivan Melo, Boris Tomasik, Giorgio Torrieri, Sascha Vogel

    We propose an application of the Kolmogorov-Smirnov test for rapidity distributions of individual events in ultrarelativistic heavy ion collisions. The test is particularly suitable to recognise non-statistical differences between the events. Thus when applied to a narrow centrality class it could indicate differences between events which would not be expect

  19. Jan A. Mamczur, Marek J. Matczak

    We derive a formula for the non-coherent wave field propagation in terms of the Fourier transformation. As a result, we find a theoretical solution of the inverse problem of image propagation in non-coherent case. However, the practical solution of the inverse problem in a numerical way leads to rapidly decreasing SNR. We also discuss origin and behavior of

  20. Nicole Schweikardt

    This paper gives a brief overview of computation models for data stream processing, and it introduces a new model for multi-pass processing of multiple streams, the so-called mp2s-automata. Two algorithms for solving the set disjointness problem wi th these automata are presented. The main technical contribution of this paper is the proof of a lower bound on

  21. Eda Baykan, Monika Henzinger, Stefan F. Keller, Sebastian De Castelberg

    As the World Wide Web is growing rapidly, it is getting increasingly challenging to gather representative information about it. Instead of crawling the web exhaustively one has to resort to other techniques like sampling to determine the properties of the web. A uniform random sample of the web would be useful to determine the percentage of web pages in a sp

  22. C. Deninger

    We study invariant functions on the reductions mod p^n of p-divisible groups. The proof of the main result, which applies to one-dimensional groups, combines results of Tate with van der Put&#39;s solution of his p-adic Corona problem. For higher dimensional groups a generalization of the p-adic Corona problem would have to be solved.

  23. Nathalie Aubrun, Mathieu Sablik

    Traditionally a tiling is defined with a finite number of finite forbidden patterns. We can generalize this notion considering any set of patterns. Generalized tilings defined in this way can be studied with a dynamical point of view, leading to the notion of subshift. In this article we establish a correspondence between an order on subshifts based on dynam

  24. Kuo Bao, Stefan Goedecker, Luigi Genovese, Alexey Neelov

    Using a systematic search algorithm we identify several types of point defects in the boron fullerene with 80 atoms. All these point defect leave the cage structure intact. In addition the cage structure is also very stable with respect to elastic deformations and addition or removal of atoms.

  25. M. Kachour

    An extension of the RINAR(1) process for modelling discrete-time dependent counting processes is considered. The model RINAR(p) investigated here is a direct and natural extension of the real AR(p) model. Compared to classical INAR(p) models based on the thinning operator, the new models have several advantages: simple innovation structure ; autoregressive c

  26. Masafumi Koike, Toshihiko Ota, Masako Saito, Joe Sato

    Parametric enhancement of the appearance probability of the neutrino oscillation under the inhomogeneous matter is studied. Fourier expansion of the matter density profile leads to a simple resonance condition and manifests that each Fourier mode modifies the energy spectrum of oscillation probability at around the corresponding energy; below the MSW resonan

  27. Yueh-Nan Chen, Guang-Yin Chen, Ying-Yen Liao, Neill Lambert

    Placing a quantum dot close to a metal nanowire leads to drastic changes in its radiative decay behavior because of evanescent couplings to surface plasmons. We show how two non-Markovian effects, band-edge and retardation, could be observed in such a system. Combined with a quantum dot p-i-n junction, these effects could be readout via current-noise measure

  28. Denis Auroux

    In this survey paper, we briefly review various aspects of the SYZ approach to mirror symmetry for non-Calabi-Yau varieties, focusing in particular on Lagrangian fibrations and wall-crossing phenomena in Floer homology. Various examples are presented, some of them new.

  29. David Eisenbud, Frank-Olaf Schreyer

    We show that the cohomology table of any coherent sheaf on projective space is a convergent--but possibly infinite--sum of positive real multiples of the cohomology tables of what we call supernatural sheaves.

  30. Xiaofei Huang

    One of the greatest scientific achievements of physics in the 20th century is the discovery of quantum mechanics. The Schrodinger equation is the most fundamental equation in quantum mechanics describing the time-based evolution of the quantum state of a physical system. It has been found that the time-independent version of the equation can be derived from

  31. Li-yun Hu, Hong-yi Fan

    We find that the exponential operator V=exp[ilamda (Q_1P_2+Q_2P_3+...+Q_{n-1}P_{n}+Q_{n}P_1)], Q_{i}, P_{i} are respectively the coordinate and momentum operators, is an n-mode squeezing operator which engenders standard squeezing. By virtue of the technique of integration within an ordered product of operators we derive V&#39;s normally ordered expansion an

  32. Pierre Kervella, Antoine Mérand, Alexandre Gallenne

    [Abridged] - Context: Circumstellar envelopes (CSEs) around Cepheids are particularly interesting as they could impact the Cepheid distance scale, and imply stellar mass loss. Aims: Our goal is to establish the spatial and spectral properties of the CSEs of L Car and RS Pup. This is done through a parametrization of the envelopes in terms of fractional flux

  33. Alain Finkel, Jean Goubault-Larrecq

    Well-structured transition systems provide the right foundation to compute a finite basis of the set of predecessors of the upward closure of a state. The dual problem, to compute a finite representation of the set of successors of the downward closure of a state, is harder: Until now, the theoretical framework for manipulating downward-closed sets was missi

  34. Rémi Rhodes

    This paper deals with homogenization of second order divergence form parabolic operators with locally stationary coefficients. Roughly speaking, locally stationary coefficients have two evolution scales: both an almost constant microscopic one and a smoothly varying macroscopic one. The homogenization procedure aims to give a macroscopic approximation that t

  35. Bartosz Fornal, Benjamin Grinstein, Mark B. Wise

    An extension of the standard model, the Lee-Wick standard model, based on ideas of Lee and Wick was recently introduced. It does not contain quadratic divergences in the Higgs mass and hence solves the hierarchy puzzle. The Lee-Wick standard model contains new heavy Lee-Wick resonances at the TeV scale that decay to ordinary particles. In this paper we exami

  36. Hongming Weng, Taisuke Ozaki, Kiyoyuki Terakura

    Construction of maximally localized Wannier functions (MLWFs) has been implemented within the linear combination of pseudo-atomic orbital (LCPAO) method. Detailed analysis using MLWFs is applied to three closely related materials, single benzene (Bz) molecule, organometallic Vanadium-Bz infinite chain, and V$_2$Bz$_{3}$ sandwich cluster. Two important result

  37. Kentaro Tanabe, Norihiro Tanahashi, Tetsuya Shiromizu

    A definition of asymptotic flatness at spatial infinity in $d$ dimensions ($d\geq 4$) is given using the conformal completion approach. Then we discuss asymptotic symmetry and conserved quantities. As in four dimensions, in $d$ dimensions we should impose a condition at spatial infinity that the &#34;magnetic&#34; part of the $d$-dimensional Weyl tensor vani

  38. Shelley C. Hansen, Paul S. Cally

    Generalized Ray Theory (GRT) provides a simple description of MHD mode transmission and conversion between magnetoacoustic fast and slow waves and is directly applicable to solar active regions. Here it is tested in a simple two-dimensional, isothermal, gravitationally-stratified model with inclined magnetic field using previously published exact solutions a

  39. Yue Chan, Grant M. Cox, Richard G. Haverkamp, James M. Hill

    In this paper, we model the mechanics of a collagen pair in the connective tissue extracellular matrix that exists in abundance throughout animals, including the human body. This connective tissue comprises repeated units of two main structures, namely collagens as well as axial, parallel and regular anionic glycosaminoglycan between collagens. The collagen

  40. T. Wong, A. Hughes, Y. Fukui, A. Kawamura

    We analyze the conditions for detection of CO(1-0) emission in the Large Magellanic Cloud (LMC), using the recently completed second NANTEN CO survey. In particular, we investigate correlations between CO integrated intensity and HI integrated intensity, peak brightness temperature, and line width at a resolution of 2.6&#39; (~40 pc). We find that significan

  41. Caleb Knoernschild, Changsoon Kim, Felix P. Lu, Jungsang Kim

    We present a beam steering system based on micro-electromechanical systems technology that features high speed steering of multiple laser beams over a broad wavelength range. By utilizing high speed micromirrors with a broadband metallic coating, our system has the flexibility to simultaneously incorporate a wide range of wavelengths and multiple beams. We d

  42. Joshua Greene

    We prove that if an alternating 3-braid knot has unknotting number one, then there must exist an unknotting crossing in any alternating diagram of it, and we enumerate such knots. The argument combines the obstruction to unknotting number one developed by Ozsváth and Szabó using Heegaard Floer homology, together with one coming from Donaldson&#39;s Theorem A

  43. N. D. Orloff, W. Tian, C. J. Fennie, C. -H. Lee

    We explore the frequency-dependent relative permittivity of Ruddlesden-Popper series Sr(n+1)Ti(n)O(3n+1) (n =1,2,3) thin films as a function of temperature and dc electric field. Interdigitated capacitors and coplanar waveguides were used to extract the frequency response from 500 Hz to 40 GHz. At room temperature, the in-plane relative permittivities obtain

  44. Jonathan Breuer, Eric Ryckman, Maxim Zinchenko

    We study CMV matrices by focusing on their right-limit sets. We prove a CMV version of a recent result of Remling dealing with the implications of the existence of absolutely continuous spectrum, and we study some of its consequences. We further demonstrate the usefulness of right limits in the study of weak asymptotic convergence of spectral measures and ra

  45. Yun Soo Myung

    We study the entropy of extremal warped black hole obtained from the topologically massive gravity with a negative cosmological constant of $Λ=-1/l^2$. We compare the entropy $S_e=πα/3G$ from the Wald formalism with $S_w=πl u /3G$ from the entropy function approach. These are the same if $α=l u$. Also we obtain the same Cardy formula when $J_e= l^3 q$ with $

  46. Nachi Gupta

    Kalman Filtering problems often have inherent and known constraints in the physical dynamics that are not exploited despite potentially significant gains (e.g., fixed speed of a motor). In this paper, we review existing methods and propose some new ideas for filtering in the presence of equality constraints. We then show that three methods for incorporating

  47. Aimee L. McNamara, Zdenka Kuncic, Kinwah Wu

    We investigate the polarization properties of Comptonized X-rays from relativistic jets in Active Galactic Nuclei (AGN) using Monte Carlo simulations. We consider three scenarios commonly proposed for the observed X-ray emission in AGN: Compton scattering of blackbody photons emitted from an accretion disk; scattering of cosmic microwave background (CMB) pho

  48. Xiuxiong Chen, Bing Wang

    In this paper, we study the moduli spaces of noncollapsed Ricci flow solutions with bounded energy and scalar curvature. We show a weak compactness theorem for such moduli spaces and apply it to study isoperimetric constant control, Kähler Ricci flow and moduli space of gradient shrinking solitons.

  49. Khee-Gan Lee

    The measurement of the optical depth to free electrons, tau_r, in the cosmic microwave background (CMB) provides an important constraint on reionization, but is degenerate to more complex reionization models. Small angular-scale CMB measurements of the kinetic Sunyaev-Zeldovich (kSZ) and Ostriker-Vishniac (OV) effects have the potential to break this degener

  50. Caitlin M. Casey, Scott C. Chapman, Tom W. B. Muxlow, Rob J. Beswick

    We present high spatial resolution MERLIN 1.4GHz radio observations of two high redshift (z~2) sources, RGJ123623 (HDF147) and RGJ123617 (HDF130), selected as the brightest radio sources from a sample of submillimetre-faint radio galaxies. They have starburst classifications from their rest-frame UV spectra. However, their radio morphologies are remarkably c

  51. Joshua S. Bloom, Daniel E. Holz, Scott A. Hughes, Kristen Menou

    It is widely expected that the coming decade will witness the first direct detection of gravitational waves (GWs). The ground-based LIGO and Virgo GW observatories are being upgraded to advanced sensitivity, and are expected to observe a significant binary merger rate. The launch of The Laser Interferometer Space Antenna (LISA) would extend the GW window to

  52. Jinwoo Lee, Dongwoo Sheen

    In order to solve backward parabolic problems F. John [{\it Comm. Pure. Appl. Math.} (1960)] introduced the two constraints &#34;$\|u(T)\|\le M$&#34; and $\|u(0) - g \| \le δ$ where $u(t)$ satisfies the backward heat equation for $t\in(0,T)$ with the initial data $u(0).$ The {\it slow-evolution-from-the-continuation-boundary} (SECB) constraint has been intro

  53. Emanuel Milman

    It is well known that isoperimetric inequalities imply in a very general measure-metric-space setting appropriate concentration inequalities. The former bound the boundary measure of sets as a function of their measure, whereas the latter bound the measure of sets separated from sets having half the total measure, as a function of their mutual distance. We s

  54. Taras Banakh, Oleg Verbitsky, Yaroslav Vorobets

    Let $D$ denote a disk of unit area. We call a subset $A$ of $D$ perfect if it has measure 1/2 and, with respect to any axial symmetry of $D$, the maximal symmetric subset of $A$ has measure 1/4. We call a curve $β$ in $D$ an yin-yang line if $β$ splits $D$ into two congruent perfect sets, $β$ crosses each concentric circle of $D$ twice, $β$ crosses each radi

  55. Fedor A. Bogomolov, Yuri G. Zarhin

    Let X be a K3 surface over a number field K. We prove that there exists a finite algebraic field extension L/K such that X has ordinary reduction at every non-archimedean place of L outside a density zero set of places.

  56. K. S. Raman, V. Oganesyan, S. L. Sondhi

    We discuss the superconductor to normal phase transition in an infinite-layered type-II superconductor in the limit where the Josephson coupling between layers is negligible. We model each layer as a neutral gas of thermally excited pancake vortices. We assume the dominant interaction between vortices in the same and in different layers is the electromagneti

  57. Hyung J. Kim, Tanaji Sen, Natalia P. Abreu, Wolfram Fischer

    The beam-beam interaction is one of the dominant sources of emittance growth and luminosity lifetime deterioration. A current carrying wire has been proposed to compensate long-range beam-beam effects in the LHC and strong localized long-range beam-beam effects are experimentally investigated in the RHIC collider. Tune shift, beam transfer function, and beam

  58. P. M. Ferreira, Howard E. Haber, Joao P. Silva

    We consider the impact of imposing generalized CP symmetries on the Higgs sector of the two-Higgs-doublet model, and identify three classes of symmetries. Two of these classes constrain the scalar potential parameters to an exceptional region of parameter space which respects either a Z_2 discrete flavor symmetry or a U(1) symmetry. We exhibit a basis-invari

  59. William H. Kinney

    This series of lectures gives a pedagogical review of the subject of cosmological inflation. I discuss Friedmann-Robertson-Walker cosmology and the horizon and flatness problems of the standard hot Big Bang, and introduce inflation as a solution to those problems, focusing on the simple scenario of inflation from a single scalar field. I discuss quantum mode

  60. M. Dotti, M. Ruszkowski, L. Paredi, M. Colpi

    We study the orbital evolution and accretion history of massive black hole (MBH) pairs in rotationally supported circumnuclear discs up to the point where MBHs form binary systems. Our simulations have high resolution in mass and space which, for the first time, makes it feasible to follow the orbital decay of a MBH either counter- or co-rotating with respec

  61. A. Curto, E. Martinez-Gonzalez, R. B. Barreiro

    We present new constraints on the non-linear coupling parameter fnl with the Wilkinson Microwave Anisotropy Probe (WMAP) data. We use an updated method based on the spherical Mexican hat wavelet (SMHW) which provides improved constraints on the fnl parameter. This paper is a continuation of a previous work by Curto et al. where several third order statistics

  62. Lilian Dominguez-Palmero, Marc Balcells

    We analyze central surface brightness mu_0, nuclear and global colors of intermediate redshift disk galaxies. On an apparent-diameter limited sample of 398 galaxies from ACS/HST Great Observatories Origins Deep Survey North (GOODS-N), we find 131 galaxies with bulges and 214 without. Up to z ~ 0.8, blue, star-forming nuclei are found in galaxies with low mu_

  63. Eyo Ita

    In this paper we provide an action related to a certain sector of general relativity where the algebra of Hamiltonian constraints forms a first class system. This action is a Dirac-consistent stand-alone action with two physical degrees of freedom per point. In this paper we provide the steps necessary to transform this new action to and from the associated

  64. Edward Ott, Andrew Pomerance

    Motivated by its relevance to various types of dynamical behavior of network systems, the maximum eigenvalue $λ_Q$ of the adjacency matrix $A$ of a network has been considered, and mean-field-type approximations to $λ_Q$ have been developed for different kinds of networks. Here $A$ is defined by $A_{ij} = 1$ ($A_{ij} = 0$) if there is (is not) a directed net

  65. Seung H. Park, Rajib Rahman, Gerhard Klimeck, Lloyd C. L. Hollenberg

    Quantum wave function engineering of dopant-based Si nano-structures reveals new physics in the solid-state, and is expected to play a vital role in future nanoelectronics. Central to any fundamental understanding or application is the ability to accurately characterize the deformation of the electron wave functions in these atom-based structures through ele

  66. Roland Bouffanais, David Lo Jacono

    This article is devoted to the study of an incompressible viscous flow of a fluid partly enclosed in a cylindrical container with an open top surface and driven by the constant rotation of the bottom wall. Such type of flows belongs to a group of recirculating lid-driven cavity flows with geometrical axisymmetry and of the prescribed boundary conditions of D

  67. Rosemary Braun, William Rowe, Carl Schaefer, Jinghui Zhang

    Recent publications have described and applied a novel metric that quantifies the genetic distance of an individual with respect to two population samples, and have suggested that the metric makes it possible to infer the presence of an individual of known genotype in a sample for which only the marginal allele frequencies are known. However, the assumptions

  68. C. R. Das, Joao Pulido, Marco Picariello

    We generalize to three active flavours a previous two flavour model for the resonant spin flavour conversion of solar neutrinos to sterile ones, a mechanism which is added to the well known LMA one. The transition magnetic moments from the muon and tau neutrinos to the sterile play the dominant role in fixing the amount of active flavour suppression. We also

  69. Pablo Cerdá-Durán, Nikolaos Stergioulas, José A. Font

    We perform two-dimensional simulations of Alfven oscillations in magnetars, modeled as relativistic stars with a dipolar magnetic field. We use the anelastic approximation to general relativistic magnetohydrodynamics, which allows for an effective suppression of fluid modes and an accurate description of Alfven waves. In addition, we compute Alfven oscillati

  70. Daniele Dominici, John F. Gunion

    We recompute the invisible Higgs decay width arising from Higgs-graviscalar mixing in the ADD model, comparing the original derivation in the non-diagonal mass basis to that in a diagonal mass basis. The results obtained are identical (and differ by a factor of 2 from the original calculation) but the diagonal-basis derivation is pedagogically useful for cla

  71. Mathias Steiner, Marcus Freitag, James C. Tsang, Vasili Perebeinos

    We study the optical properties of a single, semiconducting single-walled carbon nanotube (CNT) that is partially suspended across a trench and partially supported by a SiO2-substrate. By tuning the laser excitation energy across the E33 excitonic resonance of the suspended CNT segment, the scattering intensities of the principal Raman transitions, the radia

  72. Shu Lin, Edward Shuryak

    AdS/CFT correspondence is now widely used for study of strongly coupled plasmas, such as produced in ultrarelativistic heavy ion collisions at RHIC. While properties of equilibrated plasma and small deviations from equilibrium are by now reasonably well understood, its initial formation and thermal equilibration is much more challenging issue which remains t

  73. Deping Ye

    We obtain two sided estimates for the Bures volume of an arbitrary subset of the set of $N\times N$ density matrices, in terms of the Hilbert-Schmidt volume of that subset. For general subsets, our results are essentially optimal (for large $N$). As applications, we derive in particular nontrivial lower and upper bounds for the Bures volume of sets of separa

  74. Michael J. Williams, Martin Bureau, Michele Cappellari

    We measure the Tully-Fisher relations of 14 lenticular galaxies (S0s) and 14 spirals. We use two measures of rotational velocity. One is derived directly from observed spatially-resolved stellar kinematics and the other from the circular velocities of mass models that include a dark halo and whose parameters are constrained by detailed kinematic modelling. C

  75. Stefano Pirandola, Alessio Serafini, Seth Lloyd

    We present a detailed analysis of all the algebraic conditions an arbitrary 4x4 symmetric matrix must satisfy in order to represent the correlation matrix of a two-mode bosonic system. Then, we completely clarify when this arbitrary matrix can represent the correlation matrix of a separable or entangled Gaussian state. In this analysis, we introduce new and

  76. Eduardo S. Fraga, Leticia F. Palhares, Marcus Benghi Pinto

    In-medium Yukawa theory is part of the thermodynamics of the Standard Model of particle physics and is one of the main building blocks of most effective field theories of fermionic systems. By computing its pressure we investigate the nonperturbative thermodynamics at finite temperature and density using the optimized perturbation theory (OPT) framework. Our

  77. Valery I. Rupasov

    In the framework of four-band envelope-function formalism, developed earlier for spherical semiconductor nanocrystals, we study the electronic structure and optical properties of quantum-confined lead-salt (PbSe and PbS) nanowires (NWs) with a strong coupling between the conduction and the valence bands. We derive spatial quantization equations, and calculat

  78. Alex Fink

    The binomial ideal associated with the intersection axiom of conditional probability is shown to be radical and is expressed as intersection of toric prime ideals. This resolves a conjecture in algebraic statistics due to Cartwright and Engström.

  79. Lukas Hollenstein, Domenico Sapone, Robert Crittenden, Bjoern Malte Schaefer

    Dark energy can be studied by its influence on the expansion of the Universe as well as on the growth history of the large-scale structure. In this paper, we follow the growth of the cosmic density field in early dark energy cosmologies by combining observations of the primary CMB temperature and polarisation power spectra at high redshift, of the CMB lensin

  80. A. Colaiuda, H. Beyer, K. D. Kokkotas

    We study torsional Alfv\'en oscillations of magnetars, i.e., neutron stars with a strong magnetic field. We consider the poloidal and toroidal components of the magnetic field and a wide range of equilibrium stellar models. We use a new coordinate system (X,Y), where $X=\sqrt{a_1} \sin \theta$, $Y=\sqrt{a_1}\cos \theta$ and $a_1$ is the radial component of t

  81. Roman Bezrukavnikov, Michael Finkelberg, Victor Ostrik

    The category of character D-modules is realized as Drinfeld center of the abelian monoidal category of Harish-Chandra bimodules. Tensor product of Harish-Chandra bimodules is related to convolution of D-modules via the long intertwining functor (Radon transform) by a result of Beilinson and Ginzburg. Exactness property of the long intertwining functor on a c

  82. Peter Elliott, Kieron Burke

    The B88 exchange energy density functional (created by Becke in 1988) is a crucial part of the most popular density functional in use today, B3LYP. B88 contains one empirical parameter which was fitted to Hartree-Fock exchange energies for the noble gas atoms. We show how local approximations to exchange become relatively exact under a very specific approach

  83. H. Sotani, K. D. Kokkotas

    We study polar Alfvén oscillations of relativistic stars endowed with a strong global poloidal dipole magnetic field. Here we focus only on the axisymmetric oscillations which are studied by evolving numerically the two-dimensional perturbation equations. Our study shows that the spectrum of the polar Alfvén oscillations is discrete in contrast to the spectr

  84. Herbert Koch, Tobias Lamm

    We show the existence of a global unique and analytic solution for the mean curvature flow, the surface diffusion flow and the Willmore flow of entire graphs for Lipschitz initial data with small Lipschitz norm. We also show the existence of a global unique and analytic solution to the Ricci-DeTurck flow on euclidean space for bounded initial metrics which a

  85. Owen Pavel Fernandez Piedra, Jeferson de Oliveira

    We investigate the influence of vacuum polarization of quantum massive fields on the scalar sector of quasinormal modes in spherically symmetric black holes. We consider the evolution of a massless scalar field on the spacetime corresponding to a charged semiclassical black hole, consisting of the quantum corrected geometry of a Reissner-Nordström black hole

  86. E. M. Lipmanov

    Flavor physics, like cosmology, is likely in need of new basic ideas; the puzzles of elementary particle mass hierarchies and in particular the e-mu-tau and neutrino ones still remain mysteries. In this paper a new idea of dynamical connection between low energy 3-flavor particle mass hierarchies and electroweak charges is studied with restriction to the sim

  87. Kevin McGerty

    We give a representation-theoretic interpretation of the Langlands character duality of Frenkel and Hernandez, and show that the &#34;Langlands branching multiplicities&#34; for symmetrizable Kac-Moody Lie algebras are equal to certain tensor product multiplicities. For finite type quantum groups, the connection with tensor products can be explained in terms

  88. Hiroshi Momiji, Nicholas A. M. Monk

    Lateral inhibition resulting from a double-negative feedback loop underlies the assignment of different fates to cells in many developmental processes. Previous studies have shown that the presence of time delays in models of lateral inhibition can result in significant oscillatory transients before patterned steady states are reached. We study the impact of

  89. Emerson Sadurni, Juan Mauricio Torres, Thomas H. Seligman

    The Dirac oscillator coupled to an external two-component field can retain its solvability, if couplings are appropriately chosen. This provides a new class of integrable systems. A simplified way of solution is given, by recasting the known solution of the Dirac oscillator into matrix form; there one notices, that a block-diagonal form arises in a Hamiltoni

  90. T. Mueller, F. Xia, M. Freitag, J. Tsang

    A near-field scanning optical microscope is used to locally induce photocurrent in a graphene transistor with high spatial resolution. By analyzing the spatially resolved photo-response, we find that in the n-type conduction regime a p-n-p structure forms along the graphene device due to the doping of the graphene by the metal contacts. The modification of t

  91. Matsuo Sato

    We propose the bosonic part of an action that defines M-theory. It possesses manifest SO(1, 10) symmetry and constructed based on the Lorentzian 3-algebra associated with U(N) Lie algebra. From our action, we derive the bosonic sector of BFSS matrix theory and IIB matrix model in the naive large N limit by taking appropriate vacua. We also discuss an interac

  92. Frank E. Walter, Stefano Battiston, Frank Schweitzer

    We propose a novel trust metric for social networks which is suitable for application in recommender systems. It is personalised and dynamic and allows to compute the indirect trust between two agents which are not neighbours based on the direct trust between agents that are neighbours. In analogy to some personalised versions of PageRank, this metric makes

  93. I. L. Buchbinder, V. A. Krykhtin, L. L. Ryskina

    We apply the BRST approach, developed for higher spin field theories, to Lagrangian construction for totally antisymmetric massive fermionic fields in AdS_d space. As well as generic higher spin massive theories, the obtained Lagrangian theory is a reducible gauge model containing, besides the basic field, a number of auxiliary (Stuckelberg) fields and the o

  94. Hefeng Wang, S. Ashhab, Franco Nori

    We present an efficient quantum algorithm for preparing a pure state on a quantum computer, where the quantum state corresponds to that of a molecular system with a given number $m$ of electrons occupying a given number $n$ of spin orbitals. Each spin orbital is mapped to a qubit: the states $| 1 >$ and $| 0>$ of the qubit represent, respectively, whether th

  95. Karin Cvetko-Vah, Damjana Kokol Bukovšek, Tomaž Košir, Ganna Kudryavtseva

    We prove that the minimal cardinality of the semitransitive subsemigroup in the singular part $\IS_n\setminus \S_n$ of the symmetric inverse semigroup $\IS_n$ is $2n-p+1$, where $p$ is the greatest proper divisor of $n$, and classify all semitransitive subsemigroups of this minimal cardinality.

  96. S. -H. Baek, N. J. Curro, T. Klimczuk, H. Sakai

    We report 209Bi NMR and NQR measurements on a single crystal of the Kondo insulator U3Bi4Ni3. The 209Bi nuclear spin-lattice relaxation rate ($T_1^{-1}$) shows activated behavior and is well-fit by a spin gap of 220 K. The 209Bi Knight shift (K) exhibits a strong temperature dependence arising from 5f electrons, in which K is negative at high temperatures an

  97. A. L. Kataev, V. T. Kim

    An importance of the detailed studies of the theoretical QCD predictions for the decay width of Standard Model Higgs boson into bottom quarks, in the case when $\rm{M_H\leq 2M_W}$, is emphasized. The effects of higher order perturbative QCD corrections up to order $α_s^4$-terms are considered. The resummations of the $π^2$ terms resulting from analytical con

  98. Michelle Bucher, Tsachik Gelander

    We consider closed manifolds that admit a metric locally isometric to a product of symmetric planes. For such manifolds, we prove that the Euler characteristic is an obstruction to the existence of flat structures, confirming an old conjecture proved by Milnor in dimension 2. In particular, the Chern conjecture follows in these cases. The proof goes via a ne

  99. K. Azizi, H. Sundu, M. Bayar

    The form factors of the semileptonic $B_c\to S(AV)\ellν$ $(\ell=τ, μ, e)$ transitions, where S and AV denote the scalar $X_{c0}$ and axial vector $(X_{c1}, h_{c})$ mesons, are calculated within the framework of the three-point QCD sum rules. The heavy quark effective theory limit of the form factors are also obtained and compared with the values of the origi

  100. Fernando Q. Gouvea, Noriko Yui

    The proof of Serre&#39;s conjecture on Galois representations over finite fields allows us to show, using a method due to Serre himself, that all rigid Calabi-Yau threefolds defined over Q are modular.