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January 2010 arXiv papers — page 49

Showing 4,8014,900 of 5,448 papers

  1. Christopher M. De Vries, Shlomo Geva

    We introduce K-tree in an information retrieval context. It is an efficient approximation of the k-means clustering algorithm. Unlike k-means it forms a hierarchy of clusters. It has been extended to address issues with sparse representations. We compare performance and quality to CLUTO using document collections. The K-tree has a low time complexity that is

  2. Kausik Gangopadhyay, B. Basu

    This paper studies the size distributions of urban agglomerations for India and China. We have estimated the scaling exponent for the Zipf's law with the Indian census data for the years of 1981-2001 and the Chinese census data for 1990 and 2000. Along with the biased linear fit estimate, the maximum likelihood estimate for the Pareto and Tsallis q-expon

  3. Christopher M. De Vries, Shlomo Geva

    This paper describes the approach taken to the XML Mining track at INEX 2008 by a group at the Queensland University of Technology. We introduce the K-tree clustering algorithm in an Information Retrieval context by adapting it for document clustering. Many large scale problems exist in document clustering. K-tree scales well with large inputs due to its low

  4. Colette Moeglin, Jean-Loup Waldspurger

    We prove the local Gross-Prasad conjecture for generic L-packets of representations of special orthogonal groups. The proof uses the same result for tempered L-packets proved in a preceding paper, and irreducibility results for the induced representations of whose the elements of the L-packets are Langlands quotients.

  5. Kausik Gangopadhyay, B. Basu

    In this article, the relationship between two well-accepted empirical propositions regarding the distribution of population in cities, namely, Gibrat's law and Zipf's law, are rigorously examined using the Chinese census data. Our findings are quite in contrast with the most of the previous studies performed exclusively for developed countries. This

  6. Frederic Dorn, Fedor V. Fomin, Daniel Lokshtanov, Venkatesh Raman

    We develop two different methods to achieve subexponential time parameterized algorithms for problems on sparse directed graphs. We exemplify our approaches with two well studied problems. For the first problem, {\sc $k$-Leaf Out-Branching}, which is to find an oriented spanning tree with at least $k$ leaves, we obtain an algorithm solving the problem in tim

  7. Yuliya Lierler

    Nieuwenhuis, Oliveras, and Tinelli (2006) showed how to describe enhancements of the Davis-Putnam-Logemann-Loveland algorithm using transition systems, instead of pseudocode. We design a similar framework for several algorithms that generate answer sets for logic programs: Smodels, Smodels-cc, Asp-Sat with Learning (Cmodels), and a newly designed and impleme

  8. Sivasubramanian Somu, Hailong Wang, Younglae Kim, Laila Jaberansari

    Efforts aimed at large-scale integration of nanoelectronic devices that exploit the superior electronic and mechanical properties of single-walled carbon nanotubes (SWCNTs) remain limited by the difficulties associated with manipulation and packaging of individual SWNTs. Alternative approaches based on ultra-thin carbon nanotube networks (CNNs) have enjoyed

  9. Jeong-Eun Lee, Edwin A. Bergin, Hideko Nomura

    Despite a surface dominated by carbon-based life, the bulk composition of the Earth is dramatically carbon poor when compared to the material available at formation. Bulk carbon deficiency extends into the asteroid belt representing a fossil record of the conditions under which planets are born. The initial steps of planet formation involve the growth of pri

  10. D. Sheng, L. A. Orozco, E. Gomez

    Preparations for the anapole measurement in Fr indicate the possibility of performing a similar measurement in a chain of Rb. The sensitivity analysis based on a single nucleon model shows the potential for placing strong limits on the nucleon weak interaction parameters. There are values of the magnetic fields at much lower values than found before that are

  11. M. S. Allman, F. Altomare, J. D. Whittaker, K. Cicak

    We demonstrate coherent tunable coupling between a superconducting phase qubit and a lumped element resonator. The coupling strength is mediated by a flux-biased RF SQUID operated in the non-hysteretic regime. By tuning the applied flux bias to the RF SQUID we change the effective mutual inductance, and thus the coupling energy, between the phase qubit and r

  12. Michael A. Dopita, William P. Blair, Knox S. Long, Max Mutchler

    We present Wide Field Camera 3 images taken with the Hubble Space Telescope within a single field in the southern grand design star-forming galaxy M83. Based on their size, morphology and photometry in continuum-subtracted H$α$, [\SII], H$β$, [\OIII] and [\OII] filters, we have identified 60 supernova remnant candidates, as well as a handful of young ejecta-

  13. Jian Liu, M. Kareev, S. Prosandeev, B. Gray

    We have conducted a detailed microscopic investigation of [LaNiO3(1 u.c.)/LaAlO3(1 u.c.)]N superlattices grown on (001) SrTiO3 and LaAlO3 to explore the influence of polar mismatch on the resulting electronic and structural properties. Our data demonstrate that the initial growth on the non-polar SrTiO3 surface leads to a rough morphology and unusual 2+ vale

  14. R. W. Clay, B. J. Whelan, P. G. Edwards

    We review the importance of Centaurus A in high energy astrophysics as a nearby object with many of the properties expected of a major source of very high energy cosmic rays and gamma-rays. We examine observational techniques and the results so far obtained in the energy range from 200 GeV to above 100 EeV and attempt to fit those data with expectations of C

  15. Takumi Muto, Toshiki Maruyama, Toshitaka Tatsumi

    The effects of the $Λ$(1405) ($Λ^\ast$) on the structure of the multi-antikaonic nucleus (MKN), in which several $K^-$ mesons are embedded to form deeply bound states, are considered based on chiral symmetry combined with a relativistic mean-field theory. It is shown that additional attraction resulting from the $Λ^\ast$ pole has a sizable contribution to no

  16. John R. Britnell, Mark Wildon

    This paper addresses various questions about pairs of similarity classes of matrices which contain commuting elements. In the case of matrices over finite fields, we show that the problem of determining such pairs reduces to a question about nilpotent classes; this reduction makes use of class types in the sense of Steinberg and Green. We investigate the set

  17. Leonid Chuzhoy

    The relic abundance of thermal dark matter particles is generally assumed to be inversely proportional to their annihilation rate, which is therefore constrained by the present matter density, <sigma v> ~ 10^{-26} Omega_{dm}^{-1} cm^3 sec^{-1}. Here we point out that much lower values of <sigma v> are possible for heavy dark matter candidates (m < 10 TeV) th

  18. Satoshi Nishimoto, Masaaki Nakamura, Aroon O&#39;Brien, Peter Fulde

    We discuss the metal-insulator transition of the spinless fermion model on the Kagomé lattice at 1/3-filling. The system is analyzed using exact diagonalization, the density-matrix renormalization group methods and the random phase approximation. In the strong-coupling region, the charge-ordered ground state is consistent with the predictions of the effectiv

  19. Allison L. Strom, Aneta Siemiginowska, Mark A. Gurwell, Brandon C. Kelly

    We present multi-epoch observations from the Submillimeter Array (SMA) for a sample of 171 bright blazars, 43 of which were detected by Fermi during the first three months of observations. We explore the correlation between their gamma-ray properties and submillimeter observations of their parsec-scale jets, with a special emphasis on spectral index in both

  20. Alexander Lytchak

    We describe all affine maps from a Riemannian manifold to a metric space and all possible image spaces.

  21. S. J. Gong, W. Sheng, Z. Q. Yang, J. H. Chu

    We present an ab-initio density function theory to investigate the electronic and magnetic structures of the bilayer graphene with intercalated atoms C, N, and O. The intercalated atom although initially positioned at the middle site of the bilayer interval will finally be adsorbed to one graphene layer. Both N and O atoms favor the bridge site (i.e. above t

  22. Enrique Vazquez-Semadeni, Pedro Colin, Gilberto C. Gomez, Alan Watson

    We numerically investigate the effect of feedback from the ionizing radiation heating from massive stars on the evolution of giant molecular clouds (GMCs) and their star formation efficiency (SFE). We find that the star-forming regions within the GMCs are invariably formed by gravitational contraction. After an initial period of contraction, the collapsing c

  23. Philippe Mendels, Fabrice Bert

    The frustration of antiferromagnetic interactions on the loosely connected kagome lattice associated to the enhancement of quantum fluctuations for S=1/2 spins was acknowledged long ago as a keypoint to stabilize novel ground states of magnetic matter. Only very recently, the model compound Herbersmithite, ZnCu3(OH)6Cl2, a structurally perfect kagome antifer

  24. Yuichiro Ezoe, Kumi Ishikawa, Takaya Ohashi, Yoshizumi Miyoshi

    We report the discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter in a deep 160 ks Suzaku XIS data. The emission is distributed over ~16x8 Jovian radius and spatially associated with the radiation belts and the Io Plasma Torus. It shows a flat power-law spectrum with a photon index of 1.4+/-0.2 with the 1-5 keV X-ray luminosity of (3.3+/-0.5)x1

  25. Loren Hoffman, Thomas J. Cox, Suvendra Dutta, Lars Hernquist

    Since the violent relaxation in hierarchical merging is incomplete, elliptical galaxies retain a wealth of information about their formation pathways in their present-day orbital structure. A variety of evidence indicates that gas-rich major mergers play an important role in the formation of elliptical galaxies. We simulate 1:1 disk mergers at seven differen

  26. Moo Young Sohn, Dongseok Kim, Young Soo Kwon, Jaeun Lee

    The existence problem of the total domination vertex critical graphs has been studied in a series of articles. The aim of the present article is twofold. First, we settle the existence problem with respect to the parities of the total domination number m and the maximum degree Delta : for even m except m=4, there is no m-gamma_t-critical graph regardless of

  27. I. Boisse, F. Bouchy, B. Chazelas, S. Perruchot

    For fiber-fed spectrographs with a stable external wavelength source, scrambling properties of optical fibers and, homogeneity and stability of the instrument illumination are important for the accuracy of radial-velocimetry. Optical cylindric fibers are known to have good azimuthal scrambling. In contrast, the radial one is not perfect. In order to improve

  28. Fermi LAT Collaboration, the Fermi Pulsar Timing Consortium, :, A. A. Abdo

    We present multiwavelength studies of the 106.6 ms gamma-ray pulsar PSR J1907+06 near the TeV source MGRO J1908+06. Timing observations with Fermi result in a precise position determination for the pulsar of R.A. = 19h07m547(2), decl. = +06:02:16(2) placing the pulsar firmly within the TeV source extent, suggesting the TeV source is the pulsar wind nebula of

  29. A. D. Krisch

    There will be a review of the history of polarized proton beams, and a discussion of the unexpected and still unexplained large transverse spin effects found in several high energy proton-proton spin experiments at the ZGS, AGS, Fermilab and RHIC. Next there will be a discussion of possible future experiments on the violent collisions elastic collisions of p

  30. Erik P. Verlinde

    Starting from first principles and general assumptions Newton&#39;s law of gravitation is shown to arise naturally and unavoidably in a theory in which space is emergent through a holographic scenario. Gravity is explained as an entropic force caused by changes in the information associated with the positions of material bodies. A relativistic generalization

  31. S. K. Leggett, Ben Burningham, D. Saumon, M. S. Marley

    We present Spitzer IRAC photometry of twelve very late-type T dwarfs; nine have [3.6], [4.5], [5.8] and [8.0] photometry and three have [3.6] and [4.5] photometry only. We investigate trends with type and color for the planning and interpretation of surveys for the coldest T or Y dwarfs. Brown dwarfs with effective temperature (T_eff) below 700K emit more th

  32. Robert D. Grober

    The motion of the golf club is measured using two accelerometers mounted at different points along the shaft of the golf club, both sensitive to acceleration along the axis of the shaft. The resulting signals are resolved into differential and common mode components. The differential mode, a measure of the centripetal acceleration of the golf club, is a reas

  33. Valentin Voroshilov

    On the assumption that two electrons with the same group velocity effectively attract each other a simple model Hamiltonian is proposed to question the existence of unconventional electron pairs formed by electrons in a strong periodic potential.

  34. Jackson Levi Said, Kristian Zarb Adami

    The EPR correlation has become an integral part of quantum communications as has general relativity in classical communication theory, however when combined an apparent deterioration is observed for spin states. We consider appropriate changes in directions of measurement to exploit full EPR entanglement for a pair of particles and show that it can be deduce

  35. J. Greensite

    I present a perturbative calculation of the spectrum of the Faddeev-Popov operator in Coulomb gauge in three dimensions, and Landau gauge in two and three dimensions, with an ansatz for the gluon propagator as the non-perturbative input. The results show how the low-lying Faddeev-Popov eigenvalue spectrum is modified as the first Gribov horizon is approached

  36. D. F. Gayme, B. J. McKeon, A. Papachristodoulou, B. Bamieh

    Streamwise and quasi-streamwise elongated structures have been shown to play a significant role in turbulent shear flows. We model the mean behavior of fully turbulent plane Couette flow using a streamwise constant projection of the Navier Stokes equations. This results in a two-dimensional, three velocity component ($2D/3C$) model. We first use a steady sta

  37. Yu-Ying Zhang, Nobuhiro Okabe, Alexis Finoguenov, Graham P. Smith

    We compare X-ray hydrostatic and weak-lensing mass estimates for a sample of 12 clusters that have been observed with both XMM-Newton and Subaru. At an over-density of Δ=500, we obtain 1-M^{X}/M^{WL}=0.01+/-0.07 for the whole sample. We also divided the sample into undisturbed and disturbed sub-samples based on quantitative X-ray morphologies using asymmetry

  38. Aleksandar Petrovic

    A method for construction of analytic function f of the annihilation operator is given for the first time. f(z) is analytic on some compact domain that does not separate the complex plane. A new form of the identity is given, which is well suited for domain of function. Using Runge&#39;s polynomial approximation theorem, such a function f of the annihilation

  39. Kári Ragnarsson

    We prove structural theorems for computing the completion of a G-spectrum at the augmentation ideal of the Burnside ring of a finite group G. First we show that a G-spectrum can be replaced by a spectrum obtained by allowing only isotropy groups of prime power order without changing the homotopy type of the completion. We then show that this completion can b

  40. Jamie Smith, Michele Mosca

    This paper surveys the field of quantum computer algorithms. It gives a taste of both the breadth and the depth of the known algorithms for quantum computers, focusing on some of the more recent results. It begins with a brief review of quantum Fourier transform based algorithms, followed by quantum searching and some of its early generalizations. It continu

  41. Hye-Sung Lee, Ernest Ma

    Gauged B-L is a popular candidate for the origin of the conservation of R parity, i.e. R = (-)^{3B+L+2j}, in supersymmetry, but it fails to forbid the effective dimension-five terms arising from the superfield combinations QQQL, uude, and uddN, which allow the proton to decay. Changing it to B-x_i L, where x_e+x_μ+x_τ=3 (with x_i not equal to 1) for the thre

  42. Saurabh Maiti, Andrey V. Chubukov

    The purpose of this work is to investigate the role of the lattice in the optical Kubo sum rule in the cuprates. We compute conductivities, optical integrals W, and ΔW between superconducting and normal states for 2-D systems with lattice dispersion typical of the cuprates for four different models -- a dirty BCS model, a single Einstein boson model, a margi

  43. D. V. Vassilevich

    It is well known that for a given Poisson structure one has infinitely many star products related through the Kontsevich gauge transformations. These gauge transformations have an infinite functional dimension (i.e., correspond to an infinite number of degrees of freedom per point of the base manifold). We show that on a symplectic manifold this freedom may

  44. Mark R. Krumholz, Avishai Dekel

    We investigate the effects of radiation pressure from stars on the survival of the star-forming giant clumps in high-redshift massive disc galaxies, during the most active phase of galaxy formation. The clumps, typically of mass ~10^8-10^9 Msun and radius ~0.5-1, are formed in the turbulent gas-rich discs by violent gravitational instability and then migrate

  45. Shinsei Ryu, Tadashi Takayanagi

    Realization of topological insulators (TIs) and superconductors (TSCs), such as the quantum spin Hall effect and the Z_2 topological insulator, in terms of D-branes in string theory is proposed. We establish a one-to-one correspondence between the K-theory classification of TIs/TSCs and D-brane charges. The string theory realization of TIs and TSCs comes nat

  46. Won Sang Cho, Ji-Haeng Huh, Ian-Woo Kim, Jihn E. Kim

    We consider a degenerate or a nearly degenerate dark matter sector where a sizable magnetic moment of an almost Dirac type neutral dark matter candidate N is anticipated. Then, due to soft photon exchange, the cross-section in direct detection of N can be enhanced at low Q^2 region. We discuss the implication of this type of models in view of the recent CDMS

  47. E. S. Cypriano, A. Amara, L. M. Voigt, S. L. Bridle

    Cosmic shear requires high precision measurement of galaxy shapes in the presence of the observational Point Spread Function (PSF) that smears out the image. The PSF must therefore be known for each galaxy to a high accuracy. However, for several reasons, the PSF is usually wavelength dependent, therefore the differences between the spectral energy distribut

  48. B. Carballo Perez, M. Socolovsky

    Even if at the level of the non-relativistic limit of full QED, C is not a symmetry, the limit of this operation does exist for the particular case when the electromagnetic field is considered a classical external object coupled to the Dirac field. This result extends the one obtained when fermions are described by the Schroedinger-Pauli equation. We give th

  49. Alexey Boyarsky, Oleg Ruchayskiy, Dmytro Iakubovskyi, Matthew G. Walker

    A signal from decaying dark matter (DM) can be unambiguously distinguished from spectral features of astrophysical or instrumental origin by studying its spatial distribution. We demonstrate this approach by examining the recent claim of 0912.0552 regarding the possible DM origin of the 2.5 keV line in Chandra observations of the Milky Way satellite known as

  50. A. A. Grib, Yu. V. Pavlov

    Scattering of particles in the gravitational field of Kerr black holes is considered. It is shown that scattering energy of particles in the centre of mass system can obtain very large values not only for extremal black holes but also for nonextremal ones existing in Nature. This can be used for explanation of still unresolved problem of the origin of ultrah

  51. B. Carballo Perez, M. Socolovsky

    We find out that both the matrix and the operator CPT groups of the spin-3/2 field (with or without mass) are respectively isomorphic to $D_4\rtimes\mathbb{Z}_2$ and $Q\times\mathbb{Z}_2$. These groups are exactly the same groups as for the Dirac field, though there is no a priori reason why they should coincide.

  52. L. A. S. Mól, W. A. Moura-Melo, A. R. Pereira

    We study a modified frustrated dipolar array recently proposed by Möller and Moessner [Phys. Rev. Lett. \textbf{96}, 237202 (2006)], which is based on an array manufactured lithographically by Wang \emph{et al.} [Nature (London) \textbf{439}, 303 (2006)] and consists of introducing a height offset $h$ between islands (dipoles) pointing along the two differen

  53. A. Grigahcene, V. Antoci, L. Balona, G. Catanzaro

    Observations of the pulsations of stars can be used to infer their interior structure and test theoretical models. The main sequence $γ$ Doradus (Dor) and $δ$ Scuti (Sct) stars with masses 1.2-2.5 $M_{\sun}$ are particularly useful for these studies. The $γ$ Dor stars pulsate in high-order $g$ modes with periods of order 1 day, driven by convective blocking

  54. Ryan Williams

    A fertile area of recent research has demonstrated concrete polynomial time lower bounds for solving natural hard problems on restricted computational models. Among these problems are Satisfiability, Vertex Cover, Hamilton Path, Mod6-SAT, Majority-of-Majority-SAT, and Tautologies, to name a few. The proofs of these lower bounds follow a certain proof-by-cont

  55. M. Baldo, U. Lombardo, S. S. Pankratov, E. E. Saperstein

    We discuss the relevant progress that has been made in the last few years on the microscopic theory of the pairing correlation in nuclei and the open problems that still must be solved in order to reach a satisfactory description and understanding of the nuclear pairing. The similarities and differences with the nuclear matter case are emphasized and describ

  56. Motoo Tange

    This paper was withdrawn as Lemma 2 is incorrect.

  57. Simone Severini

    There is perfect state transfer between two vertices of a graph, if a single excitation can travel with fidelity one between the corresponding sites of a spin system modeled by the graph. When the excitation is back at the initial site, for all sites at the same time, the graph is said to be periodic. A graph is cubic if each of its vertices has a neighbourh

  58. Richard Kessler, David Cinabro, Bruce Bassett, Benjamin Dilday

    Large planned photometric surveys will discover hundreds of thousands of supernovae (SNe), outstripping the resources available for spectroscopic follow-up and necessitating the development of purely photometric methods to exploit these events for cosmological study. We present a light-curve fitting technique for SN Ia photometric redshift (photo-z) estimati

  59. Basak Karpuz

    The purpose of this paper is to establish Picard-Lindelöf theorem for local uniqueness and existence results for first-order systems of nonlinear delay dynamic equations. In the linear case, we extend our results to global existence and uniqueness of solutions on the entire interval (allowed to be unbounded above), and prove the variation of parameters formu

  60. Lutz Schroeder, Dirk Pattinson

    Hybrid logic extends modal logic with support for reasoning about individual states, designated by so-called nominals. We study hybrid logic in the broad context of coalgebraic semantics, where Kripke frames are replaced with coalgebras for a given functor, thus covering a wide range of reasoning principles including, e.g., probabilistic, graded, default, or

  61. Joyce Ann Guzik, Katie Mussack

    Solar models using the new lower abundances of Asplund et al. (2005, 2009) or Caffau et al. (2008, 2009) do not agree as well with helioseismic inferences as models that use the higher Grevesse & Noels (1993) or Grevesse & Sauval (1998) abundances. Adopting the new abundances leads to models with sound speed discrepancies of up to 1.4$%$ below the base of th

  62. John W. Byers, Michael Mitzenmacher, Georgios Zervas

    Innovative auction methods can be exploited to increase profits, with Shubik&#39;s famous &#34;dollar auction&#34; perhaps being the most widely known example. Recently, some mainstream e-commerce web sites have apparently achieved the same end on a much broader scale, by using &#34;pay-per-bid&#34; auctions to sell items, from video games to bars of gold. I

  63. Koshiroh Tsukiyama, Takaharu Otsuka, Rintaro Fujimoto

    Low-lying continuum states of exotic oxygen isotopes are studied, by introducing the Continuum-Coupled Shell Model (CCSM) characterized by an infinite wall placed very far and by an interaction for continuum coupling constructed in a close relation to realistic shell-model interaction. Neutron emission spectra from exotic oxygen isotopes are calculated by th

  64. Amarendra K. Sarma

    We present a solitary wave solution of the generalized nonlinear Schrodinger equation for dispersive permittivity and permeability using a scaling transformation and coupled amplitude-phase formulation. We have considered the third-order dispersion effect (TOD) into our model and show that soliton shift may be suppressed in a negative index material by a jud

  65. E. O. Kahya

    We present an extension of a previously suggested test of all modified theories of gravity that would reproduce MOND at low accelerations. In a class of models, called &#34;dark matter emulators&#34;, gravitational waves and other particles couple to different metrics. This leads to a detectable time lag between their detection at Earth from the same source.

  66. G. David Forney

    Shearer and McEliece [1977] showed that there is no MacWilliams identity for the free distance spectra of orthogonal linear convolutional codes. We show that on the other hand there does exist a MacWilliams identity between the generating functions of the weight distributions per unit time of a linear convolutional code C and its orthogonal code C^\perp, and

  67. M. W. Wu, J. H. Jiang, M. Q. Weng

    This article reviews the current status of spin dynamics in semiconductors which has achieved a lot of progress in the past years due to the fast growing field of semiconductor spintronics. The primary focus is the theoretical and experimental developments of spin relaxation and dephasing in both spin precession in time domain and spin diffusion and transpor

  68. F. Feroz, M. P. Hobson, R. Trotta

    In arXiv:0911.2150, Rutger van Haasteren seeks to criticize the nested sampling algorithm for Bayesian data analysis in general and its MultiNest implementation in particular. He introduces a new method for evidence evaluation based on the idea of Voronoi tessellation and requiring samples from the posterior distribution obtained through MCMC based methods.

  69. Ronald G. Douglas, Piotr W. Nowak

    We study exactness of groups and establish a characterization of exact groups in terms of the existence of a continuous linear operator, called an invariant expectation, whose properties make it a weak counterpart of an invariant mean on a group. We apply this operator to show that exactness of a finitely generated group $G$ implies the vanishing of the boun

  70. Martin Bauer, Philipp Harms, Peter W. Michor

    This paper extends parts of the results from [P.W.Michor and D. Mumford, \emph{Appl. Comput. Harmon. Anal.,} 23 (2007), pp. 74--113] for plane curves to the case of hypersurfaces in $\mathbb R^n$. Let $M$ be a compact connected oriented $n-1$ dimensional manifold without boundary like the sphere or the torus. Then shape space is either the manifold of subman

  71. Kamyar Moshksar, Amir K. Khandani

    This paper addresses an interference channel consisting of $\mathbf{n}$ active users sharing $u$ frequency sub-bands. Users are asynchronous meaning there exists a mutual delay between their transmitted codes. A stationary model for interference is considered by assuming the starting point of an interferer&#39;s data is uniformly distributed along the codewo

  72. K. Vollmayr-Lee, J. A. Roman, J. Horbach

    Molecular dynamics computer simulations are used to study the aging dynamics of SiO2 (modeled by the BKS model). Starting from fully equilibrated configurations at high temperatures T_i =5000K/3760K the system is quenched to lower temperatures T_f=2500K, 2750K, 3000K, 3250K and observed after a waiting time t_w. Since the simulation runs are long enough to r

  73. Michael Gronau, Dan Pirjol, Jure Zupan

    We show that ratios of tree and penguin amplitudes in B-> K*pi and B->rho K are two to three times larger than in B-> K pi. This allows for considerably larger CP asymmetries in the former processes than the 10% asymmetry measured in B0 -> K+pi-. We study isospin sum rules for rate asymmetries in B-> K pi, K*pi, rho K, estimating small violation from interfe

  74. Jahan Zahid

    We survey a number of results on the counting of points on hypersurfaces defined over finite fields. We also investigate when one can be guaranteed a non-singular point on a projective hypersurface and give a condition on the cardinality of the ambient field to achieve this.

  75. S. Kabana, P. Minkowski

    The hypothesis is investigated, that the thermal structure of QCD phases at and near zero chemical potentials is determined by long range coherence, inducing the gauge boson pair condensate, and its thermal extension, representing a fundamental order parameter.The condensate does not produce any latent heat as it vanishes at the critical temperature inducing

  76. G. Gennaro, S. Campbell, M. Paternostro, G. M. Palma

    We study the typical entanglement properties of a system comprising two independent qubit environments interacting via a shuttling ancilla. The initial preparation of the environments is modeled using random-matrix techniques. The entanglement measure used in our study is then averaged over many histories of randomly prepared environmental states. Under a He

  77. Frederic Bernicot, Aline Lefebvre-Lepot

    We are interested in existence results for second order differential inclusions, involving finite number of unilateral constraints in an abstract framework. These constraints are described by a set-valued operator, more precisely a proximal normal cone to a time-dependent set. Moreover we extend a numerical scheme, introduced in [8] and proved a convergence

  78. Raktim Abir, Munshi G. Mustafa

    We discuss on the critical exponent of $η/s$ for a fluid, and propose a new exponent-less measure of fluidity based on a mode-mode coupling theory. This exhibits a remarkable universality for fluids obeying a liquid-gas phase transition both in hydrodynamic as well as in nonhydrodynamic region. We show that this result is independent of the choice of the flu

  79. Sang Won Bae, Matias Korman, Yoshio Okamoto

    This paper studies the geodesic diameter of polygonal domains having h holes and n corners. For simple polygons (i.e., h = 0), the geodesic diameter is determined by a pair of corners of a given polygon and can be computed in linear time, as known by Hershberger and Suri. For general polygonal domains with h >= 1, however, no algorithm for computing the geod

  80. Patrick Eraerds, Matthieu Legre, Jun Zhang, Hugo Zbinden

    We give detailed insight into photon counting OTDR (nu-OTDR) operation, ranging from Geiger mode operation of avalanche photodiodes (APD), analysis of different APD bias schemes, to the discussion of OTDR perspectives. Our results demonstrate that an InGaAs/InP APD based nu-OTDR has the potential of outperforming the dynamic range of a conventional state-of-

  81. François Le Gall

    In this paper we consider the problem of testing whether two finite groups are isomorphic. Whereas the case where both groups are abelian is well understood and can be solved efficiently, very little is known about the complexity of isomorphism testing for nonabelian groups. Le Gall has constructed an efficient classical algorithm for a class of groups corre

  82. W. De Roeck, J. Froehlich, A. Pizzo

    We show that, in a model where a non-relativistic particle is coupled to a quantized relativistic scalar Bose field, the embedded mass shell of the particle dissolves in the continuum when the interaction is turned on, provided the coupling constant is sufficiently small. More precisely, under the assumption that the fiber eigenvectors corresponding to the p

  83. Jae-Hyung Jeon, Ralf Metzler

    Motivated by subdiffusive motion of bio-molecules observed in living cells we study the stochastic properties of a non-Brownian particle whose motion is governed by either fractional Brownian motion or the fractional Langevin equation and restricted to a finite domain. We investigate by analytic calculations and simulations how time-averaged observables (e.g

  84. Jonathan J. Heckman

    We review recent progress in realizing Grand Unified Theories (GUTs) in a strongly coupled formulation of type IIB string theory known as F-theory. Our main emphasis is on the expected low-energy phenomenology of a minimal class of F-theory GUTs. We introduce the primary ingredients in such constructions, and then present qualitative features of GUT models i

  85. T. Duguet, J. Sadoudi

    We review the notion of symmetry breaking and restoration within the frame of nuclear energy density functional methods. We focus on key differences between wave-function- and energy-functional-based methods. In particular, we point to difficulties to formulate the restoration of symmetries within the energy functional framework. The problems tackled recentl

  86. Yu. B. Ivanov

    It is argued that the experimentally observed baryon stopping may indicate (within the present experimental uncertainties) a non-monotonous behaviour as a function of the incident energy of colliding nuclei. This can be quantified by a midrapidity reduced curvature of the net-proton rapidity spectrum. The above non-monotonous behaviour reveals itself as a &#

  87. Simen Å. Ellingsen, Knut S. Gjerden, Morten Grøva, Alex Hansen

    A gravity-driven flow of grains through a narrow pipe in vacuum is studied by means of a one-dimensional model with two coefficients of restitution. Numerical simulations show clearly how density waves form when a strikingly simple criterion is fulfilled: that dissipation due to collisions between the grains and the walls of the pipe is greater per collision

  88. Anke D. Pohl

    It is well-known that reduced smooth orbifolds and proper effective foliation Lie groupoids form equivalent categories. However, for certain recent lines of research, equivalence of categories is not sufficient. We propose a notion of maps between reduced smooth orbifolds and a definition of a category in terms of marked proper effective étale Lie groupoids

  89. Sander Mooij, Marieke Postma

    We study the supergravity hybrid inflation model of Ref.[1] in the presence of a modulus field. The eta-problem is solved by a shift symmetry for the inflaton, which protects the inflaton mass even in the presence of the modulus field. Inflation is (nearly) unaffected by moduli stabilization, provided the scale of supersymmetry breaking in the post-inflation

  90. Dimitrije Markovic, Claudius Gros

    The goal of polyhomeostatic control is to achieve a certain target distribution of behaviors, in contrast to polyhomeostatic regulation which aims at stabilizing a steady-state dynamical state. We consider polyhomeostasis for individual and networks of firing-rate neurons, adapting to achieve target distributions of firing rates maximizing information entrop

  91. Valeriy I Sbitnev

    Path integrals give a possibility to compute in details routes of particles from particle sources through slit gratings and further to detectors. The path integral for a particle passing through the Gaussian slit results in the Gaussian wavepacket. The wavepackets prepared on N slits and superposed together give rise to interference pattern in the near-field

  92. Metod Saniga

    The Veldkamp space, in the sense of Buekenhout and Cohen, of the generalized quadrangle GQ(4, 2) is shown not to be a (partial) linear space by simply giving several examples of Veldkamp lines (V-lines) having two or even three Veldkamp points (V-points) in common. Alongside the ordinary V-lines of size five, one also finds V-lines of cardinality three and t

  93. Claus Heussinger, Pinaki Chaudhuri, Jean-Louis Barrat

    We present a numerical study of the flow of an assembly of frictionless soft discs at zero temperature, in the vicinity of and slightly above the jamming density. We find that some of the flow properties, such as the fluctuations in the number of contacts or the shear modulus, display a critical like behaviour that is governed by the proximity to the jamming

  94. Leilei Shi, Yiwen Wang, Ding Chen, Liyan Han

    We develop a theoretical trading conditioning model subject to price volatility and return information in terms of market psychological behavior, based on analytical transaction volume-price probability wave distributions in which we use transaction volume probability to describe price volatility uncertainty and intensity. Applying the model to high frequent

  95. H. K. Das, N. V. Voshchinnikov, V. B. Il&#39;in

    We extend and investigate the spheroidal model of interstellar dust grains used to simultaneously interpret the observed interstellar extinction and polarization curves. We compare our model with similar models recently suggested by other authors, study its properties and apply it to fit the normalized extinction $A(λ)/A_{\rm V}$ and the polarizing efficienc

  96. Benjamin Torben-Nielsen, Marylka Uusisaari, Klaus M. Stiefel

    The phase-response curve (PRC) is an important tool to determine the excitability type of single neurons which reveals consequences for their synchronizing properties. We review five methods to compute the PRC from both model data and experimental data and compare the numerically obtained results from each method. The main difference between the methods lies

  97. A. Sibirtsev, J. Haidenbauer, S. Krewald, U. -G. Meißner

    We analyse data on forward eta-meson photoproduction off a proton target and extract the eta to gamma gamma decay width utilizing the Primakoff effect. The hadronic amplitude that enters into our analysis is strongly constrained because it is fixed from a global fit to available gamma p to p eta data for differential cross sections and polarizations. We comp

  98. Charles De Clercq

    Let X be a geometrically split, geometrically irreducible variety over a field F satisfying Rost nilpotence principle. Consider a field extension E/F and a finite field K. We provide in this note a motivic tool giving sufficient conditions for so-called outer motives of direct summands of the Chow motive of X_E with coefficients in K to be lifted to the base

  99. Ofer Aharony, Leon Berdichevsky, Micha Berkooz, Yonit Hochberg

    A possible resolution of the flavor puzzle is that the fermion mass hierarchy can be dynamically generated through the coupling of the first two generation fields to a strongly coupled sector, which is approximately conformally invariant and leads to large anomalous dimensions for the first two generation fields over a large range of energies. We investigate

  100. András Némethi

    We establish two exact sequences for the lattice cohomology associated with non-degenerate plumbing graphs. The first is the analogue of the surgery exact triangle proved by Ozsvath and Szabo for the Heegaard-Floer invariant HF^+; for the lattice cohomology over Z_2-coefficients it was proved by J. Greene. Here we prove it over the integers, and we supplemen