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August 2010 arXiv papers — page 30

Showing 2,9013,000 of 5,306 papers

  1. Przemyslaw Malkiewicz

    This paper is devoted to investigation of the quantum Friedman-Robertson-Walker universe with matter satisfying the equation of state $p=wρ$, where $w$ is an almost arbitrary constant. The procedure starts with a reduced Lagrangian, which describes the system in a gauge fixed, so that the evolution parameter corresponds to the cosmological time. Then we cons

  2. D. Song

    An account of the subjective elements of quantum mechanics or of whether, as Einstein famously asked, the Moon exists when nobody is looking at it.

  3. Xin-Lin Zhou, Yong-Heng Zhao

    We propose the rest-frame 2-10 keV photon index, \ga, acting as an indicator of the bolometric correction, \lb/$L_{\rm 2-10keV}$ (where \lb~ is the bolometric luminosity and $L_{\rm 2-10keV}$ is the rest-frame 2-10 keV luminosity), in radio-quiet active galactic nuclei (AGNs). Correlations between \ga~ and both bolometric correction and Eddington ratio are p

  4. K. Daiffallah, T. Abdelatif, A. Bendib, R. Cameron

    Three-dimensional numerical simulations have been used to study the scattering of a surface-gravity wave packet by vertical magnetic flux tubes, with radii from 200 km to 3 Mm, embedded in stratified polytropic atmosphere. The scattered wave was found to consist primarily of m=0 (axisymmetric) and m=1 modes. It was found that the ratio of the amplitude of th

  5. F. Hiai, M. Mosonyi, D. Petz, C. Beny

    Quantum f-divergences are a quantum generalization of the classical notion of f-divergences, and are a special case of Petz' quasi-entropies. Many well known distinguishability measures of quantum states are given by, or derived from, f-divergences; special examples include the quantum relative entropy, the Renyi relative entropies, and the Chernoff and

  6. Petr Hajicek, Jiri Tolar

    The paper gives a systematic review of the basic ideas of (non-relativistic) quantum mechanics including all changes that result from previous work of the authors. This shows that the new theory is self-consistent and (in certain sense) complete. The most important changes are: 1) A new realist interpretation of quantum mechanics based on the observation tha

  7. Héctor Ochoa, Eduardo V. Castro, M. I. Katsnelson, F. Guinea

    We have studied electron scattering by out-of-plane (flexural) phonon modes in doped suspended graphene and its effect on charge transport. In the free-standing case (absence of strain) the flexural branch shows a quadratic dispersion relation, which becomes linear at long wavelength when the sample is under tension due to the rotation symmetry breaking. In

  8. Alejandro Chinea Manrique de Lara

    In vivo H nuclear magnetic resonance (NMR) spectroscopy is an important tool for performing non-invasive quantitative assessments of brain tumour glucose metabolism. Brain tumours are considered fast-growth tumours because of their high rate of proliferation. In addition, tumour cells exhibit profound genetic, biochemical and histological differences with re

  9. Andrzej M. Oles

    A short introduction to the complex phenomena encountered in transition metal oxides with either charge or orbital or joint charge-and-orbital order, usually accompanied by magnetic order, is presented. It is argued that all the types of above ordered phases in these systems follow from strong Coulomb interactions as a result of certain compromise between co

  10. Alexei M. Frolov, David M. Wardlaw

    The variational procedure to construct compact and accurate wave functions for three-electron atoms and ions is developed. The procedure is based on the use of six-dimensional gaussoids written in the relative four-body coordinates $r_{12}, r_{13}, r_{23}, r_{14}, r_{24}$ and $r_{34}$. The non-linear parameters in each basis function have been optimized care

  11. Girish Kulkarni, T. Roy Choudhury

    Observations of galaxy luminosity function at high redshifts typically focus on fields of view of limited sizes preferentially containing bright sources. These regions possibly are overdense and hence biased with respect to the globally averaged regions. Using a semi-analytic model based on Choudhury & Ferrara (2006) which is calibrated to match a wide range

  12. Shaon Sahoo, S. Ramasesha

    One of the long standing problems in quantum chemistry had been the inability to exploit full spatial and spin symmetry of an electronic Hamiltonian belonging to a non-Abelian point group. Here we present a general technique which can utilize all the symmetries of an electronic (magnetic) Hamiltonian to obtain its full eigenvalue spectrum. This is a hybrid m

  13. Sofiane Aoudia, Alessandro D. A. M. Spallicci

    Perturbations of Schwarzschild-Droste black holes in the Regge-Wheeler gauge benefit from the availability of a wave equation and from the gauge invariance of the wave function, but lack smoothness. Nevertheless, the even perturbations belong to the C\textsuperscript{0} continuity class, if the wave function and its derivatives satisfy specific conditions on

  14. Yu-Chieh Chung

    We construct an SU(4) spectral divisor and its factorization of types (3,1) and (2,2) based on the construction proposed in [1]. We calculate the chiral spectra of flipped SU(5) GUTs by using the spectral divisor construction. The results agree with those from the analysis of semi-local spectral covers. Our computations provide an example for the validity of

  15. Han-Yong Choi, Seung Hwan Hong

    We investigate the effects of the dynamic bosonic fluctuations on the Fermi surface reconstruction in two dimensions as a model for the underdoped cuprates. At energies larger than the boson energy $ω_b$, the dynamic nature of the fluctuations is not important and the quasi-particle dispersion exhibits the shadow feature like that induced by a static long ra

  16. Yohaï Maayan, Eddy Mayer-Wolf

    We find an explicit expression for the cross-covariance between stochastic integral processes with respect to a $d$-dimensional fractional Brownian motion (fBm) $B_t$ with Hurst parameter $H>1/2$, where the integrands are vector fields applied to $B_t$. It provides, for example, a direct alternative proof of Y. Hu and D. Nualart's result that the stochas

  17. Yair Shokef, Anton Souslov, Tom C. Lubensky

    Geometrically frustrated materials have a ground-state degeneracy that may be lifted by subtle effects, such as higher order interactions causing small energetic preferences for ordered structures. Alternatively, ordering may result from entropic differences between configurations in an effect termed order-by-disorder. Motivated by recent experiments in a fr

  18. Manoranjan Ghosh, R S Ningthoujam, R. K. Vatsa, D. Das

    ZnO nanoparticles (NP) of size less than around 20 nm inside a chamber exhibits complete reduction in their visible photoluminescence (PL) intensity when partial pressure of oxygen in the surrounding gaseous environment is decreased by evacuation. However the visible PL from ZnO nanoparticles are insensitive to the gases like N2, He and Ar. The rate of chang

  19. Zhenhua Wu

    We investigate theoretically the transmission properties through a p-n-p junction on graphene. Here we show that the electronic transport property presents deep analogies with light propagation. It originates from the similarity between the linear spectrum of the Dirac fermions and photons that obey the Maxwell's equations. We demonstrate the p-n-p chann

  20. Yoshikazu Mizuguchi, Keita Deguchi, Toshinori Ozaki, Masanori Nagao

    We have synthesized single crystals of FeTe1-xSx and investigated the structural and physical properties. The actual S concentration was found to be significantly smaller than the starting nominal value. The solubility limit of S for the Te site for the crystals grown using a self-flux method was estimated to be around 12 %. Although a suppression of antifer

  21. Burra G. Sidharth

    The LHC in Geneva is already operating at a total energy of $7 TeV$ and hopefully after a pause in 2012, it will attain its full capacity of $14 TeV$ in 2013. These are the highest energies achieved todate in any accelerator. It is against this backdrop that it is worthwhile to revisit very high energy collisions of Fermions (Cf. also \cite{bgspp}). We will

  22. Jeffrey M. McMahon, Stephen K. Gray, George C. Schatz

    We demonstrate that the electric field enhancement that occurs in a gap between two closely spaced nanostructures, such as metallic nanoparticles, is the result of a transverse electromagnetic waveguide mode. We derive an explicit semianalytic equation for the enhancement as a function of gap size, which we show has a universal qualitative behavior in that i

  23. N. Haba, S. Matsumoto

    We propose a novel mechanism to generate a suitable baryon asymmetry from dark (hidden) sector. This is a Baryogenesis through a reverse pathway of the "asymmetric dark matter" scenario. In the mechanism, the asymmetry of dark matter is generated at first, and it is partially transferred into a baryon asymmetry in the standard model sector. This mech

  24. Xingang Chen

    We compute a novel type of large non-Gaussianity due to small periodic features in general single field inflationary models. We show that the non-Bunch-Davies vacuum component generated by features, although has a very small amplitude, can have significant impact on the non-Gaussianity. Three mechanisms are turned on simultaneously in such models, namely the

  25. B. Whitworth

    This paper links the conjecture that the physical world is a virtual reality to the findings of modern physics. What is usually the subject of science fiction is here proposed as a scientific theory open to empirical evaluation. We know from physics how the world behaves, and from computing how information behaves, so whether the physical world arises from o

  26. Coco Krumme, Manuel Cebrian, Alex Pentland

    Much of economic theory is built on observations of aggregate, rather than individual, behavior. Here, we present novel findings on human shopping patterns at the resolution of a single purchase. Our results suggest that much of our seemingly elective activity is actually driven by simple routines. While the interleaving of shopping events creates randomness

  27. Thomas C Conway, Andrew J Bromage

    Motivation: Second generation sequencing technology makes it feasible for many researches to obtain enough sequence reads to attempt the de novo assembly of higher eukaryotes (including mammals). De novo assembly not only provides a tool for understanding wide scale biological variation, but within human bio-medicine, it offers a direct way of observing both

  28. Amrit Poudel, Maxim G. Vavilov

    We analyze the effect of environment on the gate operation of flux-biased phase qubits. We employ the master equation for a reduced density matrix of the qubit system coupled to an Ohmic environment, described by the Caldeira-Leggett model. Numerically solving this equation, we evaluate the gate error as a function of energy splitting between qubit states, j

  29. Alexandre Megretski

    Several variations of the classical Kalman-Yakubovich-Popov Lemma, as well the associated minimax theorem are presented.

  30. Daniel A. Mitchell, Lincoln J. Greenhill, Stephen M. Ord, Gianni Bernardi

    It is shown that the excellent Murchison Radio-astronomy Observatory site allows the Murchison Widefield Array to employ a simple RFI blanking scheme and still calibrate visibilities and form images in the FM radio band. The techniques described are running autonomously in our calibration and imaging software, which is currently being used to process an FM-b

  31. Oscar Sandoval Carlos

    This document presents the integration of design patterns and mobile applications, in the development of software management of plates (SIGEP) that allows to support in the solutions to problematics that they appear in the process of maintaining of plates copper cathodes of a Mining Company, in our case for Quebrada Blanca S.A. (CMQB S.A.). These problematic

  32. A. A. Arkhipov

    Three tightly inter-related topics have been discussed: the $pp(p\bar p)$ total cross section; the single diffraction dissociation cross section; the $p(\bar p)d$ total cross section and the defect of the total cross section in scattering from deuteron.

  33. L. Palodhi, F. Califano, F. Pegoraro

    The transition between non resonant (Weibel-type) and resonant (whistler) instabilities is investigated numerically in plasma configurations with an ambient magnetic field of increasing amplitudes. The Vlasov-Maxwell system is solved in a configuration where the fields have three components but depend only on one coordinate and on time. The nonlinear evoluti

  34. Ch. Antonopoulos, T. Manos, Ch. Skokos

    The Smaller Alignment Index (SALI) is a very useful and efficient indicator that can distinguish rapidly and with certainty between ordered and chaotic motion in Hamiltonian systems. This is based on the different behavior of the SALI in the two cases, as it fluctuates around non-zero values for ordered orbits and converges exponentially to zero for chaotic

  35. H. Ögelman, N. Aksaker, S. Anılan, H. Dereli

    2 years worth of archival FERMI-LAT data was used to search for the gamma-ray emission from the Andromeda galaxy. The data show no noticeable elliptical image. Subsequent on-off source aperture photometry analysis using a CO image template show a 7 sigma excess in the number of on-source apertures in comparison to the off-source apertures, yielding a flux of

  36. T. Gokmen, Medini Padmanabhan, M. Shayegan

    We measure the renormalized effective mass (m*) of interacting two-dimensional electrons confined to an AlAs quantum well while we control their distribution between two spin and two valley subbands. We observe a marked contrast between the spin and valley degrees of freedom: When electrons occupy two spin subbands, m* strongly depends on the valley occupati

  37. Jeffrey S. Guasto, Karl A. Johnson, J. P. Gollub

    We present the first time-resolved measurements of the oscillatory velocity field induced by swimming unicellular microorganisms. Confinement of the green alga C. reinhardtii in stabilized thin liquid films allows simultaneous tracking of cells and tracer particles. The measured velocity field reveals complex time-dependent flow structures, and scales invers

  38. Raquel M. Lopez, Benjamin R. Morin, Sergei K. Suslov

    We discuss explicit solutions of the logistic model with variable parameters. Classical data on the sunflower seeds growth are revisited as a simple application of the logistic model with periodic coefficients. Some applications to related biological systems are briefly reviewed.

  39. R. Walter, C. Farnier, J. -C. Leyder

    Eta Carinae is the colliding wind binary with the largest mass loss rate in our Galaxy and the only one in which hard X-ray emission has been detected. Eta Carinae is therefore a primary candidate to search for particle acceleration by probing its gamma-ray emission. We used the first 21 months of Fermi/LAT data to extract gamma-ray (0.2-100 GeV) images, spe

  40. Sudhakar Sahoo, Ipsita Mohanty, Garisha Chowdhary, Arpit Panigrahi

    In this paper the theory of 2-Variable Boolean Operation (2-VBO) has been discussed on a pair of n-bit strings. 2-VBO serves to bring out the relation between numbers which when plot on a 2-D surface form interesting patterns; patterns that may be fixed, periodic, chaotic or complex. Some of these patterns represent natural fractals. This paper also provides

  41. Ricardo Riaza

    The recent design of a nanoscale device with a memristive characteristic has had a great impact in nonlinear circuit theory. Such a device, whose existence was predicted by Leon Chua in 1971, is governed by a charge-dependent voltage-current relation of the form $v=M(q)i$. In this paper we show that allowing for a fully nonlinear characteristic $v=η(q, i)$ i

  42. Colleen K. Kelly, Michael G. Bowler, Jeffrey B. Joy, John N. Williams

    The ecological principle of limiting similarity dictates that species similar in resource requirements will compete, with the superior eventually excluding the inferior competitor from the community. The observation that nonetheless apparently similar species comprise a significant proportion of the diversity in any given community has led to suggestions tha

  43. Lakshmi Prasad Natarajan, B. Sundar Rajan

    In this paper, we give a new framework for constructing low ML decoding complexity Space-Time Block Codes (STBCs) using codes over the finite field $\mathbb{F}_4$. Almost all known low ML decoding complexity STBCs can be obtained via this approach. New full-diversity STBCs with low ML decoding complexity and cubic shaping property are constructed, via codes

  44. Homin Shin, Gregory M. Grason

    We construct a coarse-grained model of parallel actin bundles crosslinked by compact, globular bundling proteins, such as fascin and espin, necessary components of filapodial and mechanosensory bundles. Consistent with structural observations of bundles, we find that the optimal geometry for crosslinking is overtwisted, requiring a coherent structural change

  45. E. V. Castro, H. Ochoa, M. I. Katsnelson, R. V. Gorbachev

    The temperature dependence of the mobility in suspended graphene samples is investigated. In clean samples, flexural phonons become the leading scattering mechanism at temperature $T \gtrsim 10\,\,$K, and the resistivity increases quadratically with $T$. Flexural phonons limit the intrinsic mobility down to a few $\text{m}^2/\text{Vs}$ at room $T$. Their eff

  46. D. W. Boukhvalov, I. V. Solovyev

    Using density-functional theory with the on-site Coulomb correction (the LDA+U method), we perform the structural optimization of BiMnO3 by starting from different experimentally reported structures. We confirm that irrespectively on the starting condition, all calculations converge to the same centrosymmetric structure, in agreement with the previous findin

  47. Yukihiko Nakata

    In this paper, we investigate global dynamics for a system of delay differential equations which describes a virus-immune interaction in \textit{vivo}. The model has two distributed time delays describing time needed for infection of cell and virus replication. Our model admits three possible equilibria, an uninfected equilibrium and infected equilibrium wit

  48. Jingsong He, Yishen Li

    The designable integrability(DI) of the variable coefficient nonlinear Schrödinger equation (VCNLSE) is first introduced by construction of an explicit transformation which maps VCNLSE to the usual nonlinear Schrödinger equation(NLSE). One novel feature of VCNLSE with DI is that its coefficients can be designed artificially and analytically by using transfor

  49. B. Y. Sun, P. Zhang, M. W. Wu

    We investigate the spin relaxation limited by the D'yakonov-Perel' mechanism in $n$-type (111) GaAs quantum wells, by means of the kinetic spin Bloch equation approach. In (111) GaAs quantum wells, the in-plane effective magnetic field from the D'yakonov-Perel' term can be suppressed to zero on a special momentum circle under the proper gate

  50. Gert de Cooman, Filip Hermans, Alessandro Antonucci, Marco Zaffalon

    We focus on credal nets, which are graphical models that generalise Bayesian nets to imprecise probability. We replace the notion of strong independence commonly used in credal nets with the weaker notion of epistemic irrelevance, which is arguably more suited for a behavioural theory of probability. Focusing on directed trees, we show how to combine the giv

  51. M. Kama, C. Dominik, S. Maret, F. van der Tak

    In contrast with numerous studies on the physical and chemical structure of low- and high-mass protostars, much less is known about their intermediate-mass counterparts, a class of objects that could help to elucidate the mechanisms of star formation on both ends of the mass range. We present the first results from a rich HIFI spectral dataset on an intermed

  52. D. Shulyak, A. Reiners, S. Wende, O. Kochukhov

    We present first quantitative results of the surface magnetic field measurements in selected M-dwarfs based on detailed spectra synthesis conducted simultaneously in atomic and molecular lines of the FeH Wing-Ford $F^4\,Δ-X^4\,Δ$ transitions. A modified version of the Molecular Zeeman Library (MZL) was used to compute Landé g-factors for FeH lines in differe

  53. Partha Ghose

    It is shown that having degenerate ground states over the domain of the wavefunction of a system is a sufficient condition for a quantum system to act as a measuring apparatus for the system. Measurements are then instances of spontaneous symmetry breaking to one of these ground states, induced by environmental perturbations. Together with non-Boolean holism

  54. Limeng Xia, Naihong Hu

    In this work, we introduce a new concept which is obtained by defining a new compatibility condition between Lie algebras and Lie coalgebras. With this terminology, we describe the interrelation between the Killing form and the adjoint representation in a new perspective.

  55. Jiao Zhang, Naihong Hu

    For any strong smash product algebra $A\#_{_R}B$ of two algebras $A$ and $B$ with a bijective morphism $R$ mapping from $B\ot A$ to $A\ot B$, we construct a cylindrical module $A\natural B$ whose diagonal cyclic module $Δ_{\bullet}(A\natural B)$ is graphically proven to be isomorphic to $C_{\bullet}(A\#_{_R}B)$ the cyclic module of the algebra. A spectral se

  56. Hiroshi Takatsu, Shingo Yonezawa, Satoshi Fujimoto, Yoshiteru Maeno

    We experimentally reveal an unconventional anomalous Hall effect (UAHE) in a quasi-two-dimensional triangular-lattice antiferromagnet PdCrO2. Using high quality single crystals of PdCrO2, we found that the Hall resistivity deviates from the conventional behavior below T* = 20 K, noticeably lower than TN = 37.5 K, at which Cr^{3+} (S=3/2) spins order in a 120

  57. Martin Rubey

    We present a formula for the number of distinct ribbon Schur functions of given size and height.

  58. Dao Xuan Viet, Hikaru Kawamura

    The nature of the ordering of the one-dimensional Heisenberg spin-glass model with a long-range power-law interaction is studied by extensive Monte Carlo simulations, with particular attention to the issue of the spin-chirality decoupling/coupling. Large system sizes up to $L=4096$ are studied. With varying the exponent $σ$ describing the power-law interacti

  59. Hoonkyung Lee, Marvin L. Cohen, Steven G. Louie

    Using the ab initio pseudopotential density functional method, we investigate the functionalization of halogen molecules into graphene-based nanostructures with zigzag and armchair edges. We find that halogen molecules adsorb through chemisorption on the zigzag edge carbon atoms with a binding energy of ~1-5 eV and their adsorption on a perfect zigzag edge i

  60. Hoonkyung Lee

    We investigate the functionalization of functional groups to graphene nanoribbons with zigzag and armchair edges using first principles calculations. We find that the formation energy for the configuration of the functional groups functionalized to the zigzag edge is ~0.2 eV per functional group lower than that to the armchair edge. The formation energy diff

  61. S. A. Parameswaran, R. Shankar, S. L. Sondhi

    A free Fermi gas has, famously, a superconducting susceptibility that diverges logarithmically at zero temperature. In this paper we ask whether this is still true for a Fermi liquid and find that the answer is that it does {\it not}. From the perspective of the renormalization group for interacting fermions, the question arises because a repulsive interacti

  62. Sungmin Lee, Verónica C Ramenzoni, Petter Holme

    We understand the dynamics of the world around us as by associating pairs of events, where one event has some influence on the other. These pairs of events can be aggregated into a web of memories representing our understanding of an episode of history. The events and the associations between them need not be directly experienced-they can also be acquired by

  63. Fei Wang

    Log Enriques surface is a generalization of K3 and Enriques surface. We will classify all the rational log Enriques surfaces of rank 18 by giving concrete models for the realizable types of these surfaces.

  64. Wei-Cheng Lee, Congjun Wu

    The thermodynamic properties of the bilayer Sr$_3$Ru$_2$O$_7$ at very low temperatures are investigated by a realistic tight-binding model with the on-site interactions treated at the mean-field level. Due to the strong spin-orbit coupling, the band structure undergoes a significant change in Fermi surface topology as the external magnetic field is applied,

  65. J. W. Moffat

    An ultraviolet complete quantum gravity theory is formulated in which vertex functions in Feynman graphs are entire functions and the propagating graviton is described by a local, causal propagator. The cosmological constant problem is investigated in the context of the ultraviolet complete quantum gravity.

  66. Sasha Anan'in, Misha Verbitsky

    Let M be a compact hyperkaehler manifold, and W the coarse moduli of complex deformations of M. Every positive integer class v in $H^2(M)$ defines a divisor $D_v$ in W consisting of all algebraic manifolds polarized by v. We prove that every connected component of this divisor is dense in W.

  67. Kyle C. Smith, Meheboob Alam, Timothy S. Fisher

    A mechanically-based structural optimization method is utilized to explore the phenomena of jamming for assemblies of frictionless Platonic solids. Systems of these regular convex polyhedra exhibit mechanically stable phases with density substantially less than optimal for a given shape, revealing that thermal motion is necessary to access high density phase

  68. Frank Simon

    Imaging hadronic calorimeters with scintillator readout use small scintillator tiles individually read out by silicon photomultipliers to achieve the necessary granularity needed for sophisticated reconstruction algorithms at future collider detectors. For a second generation prototype of the CALICE analog HCAL new, 3 mm thick scintillator tiles with an embe

  69. Andrew Crabbe, Graham J. Leuschke

    Complete hypersurfaces of dimension at least 2 and multiplicity at least 4 have wild Cohen-Macaulay type.

  70. Massimiliano Esposito, Ryoichi Kawai, Katja Lindenberg, Christian Van den Broeck

    We study the efficiency at maximum power, $η^*$, of engines performing finite-time Carnot cycles between a hot and a cold reservoir at temperatures $T_h$ and $T_c$, respectively. For engines reaching Carnot efficiency $η_C=1-T_c/T_h$ in the reversible limit (long cycle time, zero dissipation), we find in the limit of low dissipation that $η^*$ is bounded fro

  71. Alexander Karabegov

    Given a formal symplectic groupoid $G$ over a Poisson manifold $(M, π_0)$, we define a new object, an infinitesimal deformation of $G$, which can be thought of as a formal symplectic groupoid over the manifold $M$ equipped with an infinitesimal deformation $π_0 + επ_1$ of the Poisson bivector field $π_0$. The source and target mappings of a deformation of $G

  72. The ATLAS Collaboration

    A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the Large Hadron Collider (LHC) and correspond to an integrated luminosity of 315 nb^-1 collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section

  73. Hari S. Gupta, Deepak D'Souza, Raghavan Komondoor, Girish M. Rama

    A number of companies are trying to migrate large monolithic software systems to Service Oriented Architectures. A common approach to do this is to first identify and describe desired services (i.e., create a model), and then to locate portions of code within the existing system that implement the described services. In this paper we describe a detailed case

  74. Chris Wendl

    We show that the pre-order defined on the category of contact manifolds by arbitrary symplectic cobordisms is considerably less rigid than its counterparts for exact or Stein cobordisms: in particular, we exhibit large new classes of contact 3-manifolds which are symplectically cobordant to something overtwisted, or to the tight 3-sphere, or which admit symp

  75. Forrest S. Mozer, Arthur Hull

    Magnetic field reconnection is often invoked to explain electromagnetic energy conversion in planetary magnetospheres, stellar coronae, and other astrophysical objects. Because of the huge dynamic range of magnetic fields in these bodies, it is important to understand energy conversion as a function of magnetic field strength and related parameters. It is co

  76. Jonathan Ben-Artzi

    We consider the question of linear instability of an equilibrium of the Relativistic Vlasov-Maxwell (RVM) System that has a strong magnetic field. Standard instability results deal with systems where there are fewer particles with higher energies. In this paper we extend those results to the class of equilibria for which the number of particles does not depe

  77. Massimiliano Sassoli de Bianchi

    Founding our analysis on the Geneva-Brussels approach to quantum mechanics, we use conventional macroscopic objects as guiding examples to clarify the content of two important results of the beginning of twentieth century: Einstein-Podolsky-Rosen's reality criterion and Heisenberg's uncertainty principle. We then use them in combination to show that

  78. Alexandra Monzner, Frol Zapolsky

    We compare two functionals defined on the space of continuous functions with compact support in an open neighborhood of the zero section of the cotangent bundle of a torus. One comes from Viterbo's symplectic homogenization while the other from the Calabi quasi-states due to Entov and Polterovich. In dimension 2 we are able to say when these two function

  79. Michael Klawunn, Alexander Pikovski, Luis Santos

    Low-energy two-dimensional scattering is particularly sensitive to the existence and properties of weakly-bound states. We show that interaction potentials $V(r)$ with vanishing zero-momentum Born approximation $\int d^2r V(r)=0$ lead to an anomalously weak bound state which crucially modifies the two-dimensional scattering properties. This anomalous case is

  80. G. Heinrich, G. Ossola, T. Reiter, F. Tramontano

    We present a new approach to the reduction of one-loop amplitudes obtained by reconstructing the tensorial expression of the scattering amplitudes. The reconstruction is performed at the integrand level by means of a sampling in the integration momentum. There are several interesting applications of this novel method within existing techniques for the reduct

  81. Narad Rampersad, Jeffrey Shallit, Ming-wei Wang

    A language L is closed if L = L*. We consider an operation on closed languages, L-*, that is an inverse to Kleene closure. It is known that if L is closed and regular, then L-* is also regular. We show that the analogous result fails to hold for the context-free languages. Along the way we find a new relationship between the unbordered words and the prime pa

  82. Bijan Davvaz, Akbar Dehghan-Nezhad

    Hypergroups first were introduced by Marty in 1934. Up to now many researchers have been working on this field of modern algebra and developed it. It is purpose of this paper to provide examples of hypergroups associated with chemistry. The examples presented are connected to construction from chain reactions.

  83. Mohamed Boucetta-Alberto Medina

    A Lie group is called orthogonal if it carries a bi-invariant pseudo Riemannian metric. Oscillator Lie groups constitutes a subclass of the class of orthogonal Lie groups. In this paper, we determine the Lie bialgebra structures and the solutions of the classical Yang-Baxter equation on a generic class of oscillator Lie groups. On the other hand, we show tha

  84. Arnab Rai Choudhuri

    The most promising model for explaining the origin of solar magnetism is the flux transport dynamo model, in which the toroidal field is produced by differential rotation in the tachocline, the poloidal field is produced by the Babcock--Leighton mechanism at the solar surface and the meridional circulation plays a crucial role. After discussing how this mode

  85. Kosuke Yoshioka, Eunmi Chae, Makoto Kuwata-Gonokami

    Bose-Einstein condensation (BEC) is a quantum mechanical phenomenon directly linked to the quantum statistics of bosons. While cold atomic gases provide a new arena for exploring the nature of BEC, a long-term quest to confirm BEC of excitons, quasi-Bose particles formed as a bound state of an electron-hole pair, has been underway since its theoretical predi

  86. Bruno Merín, Joanna M. Brown, Isa Oliveira, Gregory J. Herczeg

    Understanding how disks dissipate is essential to studies of planet formation. However, identifying exactly how dust and gas dissipates is complicated due to difficulty in finding objects clearly in the transition of losing their surrounding material. We use Spitzer IRS spectra to examine 35 photometrically-selected candidate cold disks (disks with large inn

  87. Chikako Uchiyama, Masaki Aihara

    The linear transient response of a two-level system coupled with an environmental system is studied under correlated and factorized initial conditions. We find that the transient response in these cases differs significantly from each other, especially for strong system-environment interaction at intermediate temperatures. This means that it is necessary to

  88. Paul Beame, Widad Machmouchi

    We show that any quantum algorithm deciding whether an input function $f$ from $[n]$ to $[n]$ is 2-to-1 or almost 2-to-1 requires $Θ(n)$ queries to $f$. The same lower bound holds for determining whether or not a function $f$ from $[2n-2]$ to $[n]$ is surjective. These results yield a nearly linear $Ω(n/\log n)$ lower bound on the quantum query complexity of

  89. Jeff Hamrick, Yifei Huang, Constantinos Kardaras, Murad Taqqu

    We develop a maximum penalized quasi-likelihood estimator for estimating in a nonparametric way the diffusion function of a diffusion process, as an alternative to more traditional kernel-based estimators. After developing a numerical scheme for computing the maximizer of the penalized maximum quasi-likelihood function, we study the asymptotic properties of

  90. Tomaz Prosen

    We propose a simple complexity indicator of classical Liouvillian dynamics, namely the separability entropy, which determines the logarithm of an effective number of terms in a Schmidt decomposition of phase space density with respect to an arbitrary fixed product basis. We show that linear growth of separability entropy provides stricter criterion of comple

  91. Shi Pu, Jian-hua Gao, Qun Wang

    We provide a consistent description of the kinetic equation with triangle anomaly which is compatible with the entropy principle of the second law of thermodynamics and the charge/energy-momentum conservation equations. In general an anomalous source term is necessary to ensure that the equations for the charge and energy-momentum conservation are satisfied

  92. Wei Wen

    Quantum measurement problem is still unconsensus since it has existed many years and inspired a large of literature in physics and philosophy. We show it can be subsumed into the quantum theory if we extend the Feynman path integral by considering the relativistic effect of Feynman paths. According to this extended theory, we deduce not only the Klein-Gordon

  93. Gene I. Sher

    In this paper I present a novel type of Topology and Weight Evolving Artificial Neural Network (TWEANN) system called Modular Discover & eXplore Neural Network (DXNN). Modular DXNN utilizes a hierarchical/modular topology which allows for highly scalable and dynamically granular systems to evolve. Among the novel features discussed in this paper is a simple

  94. Biniyam Tesfaye Taddese, Thomas M. Antonsen, Edward Ott, Steven M. Anlage

    Classical analogs of the quantum mechanical concepts of the Loschmidt Echo and quantum fidelity are developed with the goal of detecting small perturbations in a closed wave chaotic region. Sensing techniques that employ a one-recording-channel time-reversal-mirror, which in turn relies on time reversal invariance and spatial reciprocity of the classical wav

  95. Sanghoon Baek

    Let $1\leq m \leq n$ be integers with $m|n$ and $\cat{Alg}_{n,m}$ the class of central simple algebras of degree $n$ and exponent dividing $m$. In this paper, we find new, improved upper bounds for the essential dimension and 2-dimension of $\cat{Alg}_{n,2}$. In particular, we show that $\ed_{2}(\cat{Alg}_{16,2})=24$ over a field $F$ of characteristic differ

  96. Akaki Tikaradze

    In this note we describe centralizers of Toeplitz operators with polynomial symbols on the Bergman space. As a consequence it is shown that if an element of the norm closed algebra generated by all Toeplitz operators commutes with a Toeplitz operator of a noncon- stant polynomial, then this element is a Toeplitz operator of a bounded holomorphic function.

  97. P. Pastor, J. Klacka, L. Komar

    Orbital evolution of an interplanetary dust particle under action of an interstellar gas flow is investigated. Secular time derivatives of the particle orbital elements, for arbitrary orbit orientation, are presented. An important result concerns secular evolution of semi-major axis. Secular semi-major axis of the particle on a bound orbit decreases under th

  98. Partha Konar, Konstantin T. Matchev, Myeonghun Park, Gaurab K. Sarangi

    We apply a model-independent, agnostic approach to the collider phenomenology of supersymmetry (SUSY), in which all mass parameters are taken as free inputs at the weak scale. We consider the gauginos, higgsinos, and the first two generations of sleptons and squarks, and analyze all possible mass hierarchies among them ($4\times 8!=161,280$ in total) in whic

  99. J. -M. Desert, D. Sing, A. Vidal-Madjar, G. Hebrard

    We present a new primary transit observation of the hot-jupiter HD189733b, obtained at 3.6 microns with the Infrared Array Camera (IRAC) onboard the Spitzer Space Telescope. Previous measurements at 3.6 microns suffered from strong systematics and conclusions could hardly be obtained with confidence on the water detection by comparison of the 3.6 and 5.8 mic

  100. Hester Graves

    Lenstra's concept of Euclidean ideals generalizes the Euclidean algorithm; a domain with a Euclidean ideal has cyclic class group, while a domain with a Euclidean algorithm has trivial class group. This paper generalizes Harper's variation of Motzkin's lemma to Lenstra's concept of Euclidean ideals and then uses the large sieve to obtain grow