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October 2010 arXiv papers — page 3

Showing 201300 of 6,460 papers

  1. Claude Cibils, Maria Julia Redondo, Andrea Solotar

    Let k be a field. We attach a CW-complex to any Schurian k-category and we prove that the fundamental group of this CW-complex is isomorphic to the intrinsic fundamental group of the k-category. This extends previous results by J.C. Bustamante. We also prove that the Hurewicz morphism from the vector space of abelian characters of the fundamental group to th

  2. Vladimir Retakh, Shirlei Serconek, Robert Wilson

    We give a homological interpretation of the coefficients of the Hilbert series for an algebra associated with a directed graph and its dual algebra. This allows us to obtain necessary conditions for Koszulity of such algebras in terms of homological properties of the graphs. We use our results to construct algebras with a prescribed Hilbert series.

  3. R. Domínguez-Tenreiro, J. Oñorbe, F. Martínez-Serrano, A. Serna

    The mass assembly and star formation histories of massive galaxies identified at low redshift z in different cosmological hydrodynamical simulations, have been studied through a detailed follow-up backwards in time of their constituent mass elements (sampled by particles) of different types. Then, the configurations they depict at progressively higher zs hav

  4. Ali Akbar Abolhasani, Hassan Firouzjahi, Mohammad Hossein Namjoo

    We consider a variant of hybrid inflation where the waterfall phase transition happens during inflation. By adjusting the parameters associated with the mass of the waterfall field we arrange that the phase transition is not sharp so inflation can proceed for about 50-60 e-folds after the waterfall phase transition. We show that one can work in the limit whe

  5. T. S. Nigmanov, D. Rajaram, M. J. Longo, U. Akgun

    We have measured cross sections for forward neutron production from a variety of targets using proton beams from the Fermilab Main Injector. Measurements were performed for proton beam momenta of 58 GeV/c, 84 GeV/c, and 120 GeV/c. The cross section dependence on the atomic weight (A) of the targets was found to vary as $A^(alpha)$ where $α$ is $0.46\pm0.06$

  6. Ye Tian, Aylin Yener

    This work studies the Gaussian interference channel (IC) with a relay, which transmits and receives in a band that is orthogonal to the IC. The channel associated with the relay is thus an out-of-band relay channel (OBRC). The focus is on a symmetric channel model, in order to assess the fundamental impact of the OBRC on the signal interaction of the IC, in

  7. Debasish Borah, Urjit A. Yajnik

    We explore the unification of gauge couplings and fermion masses in two different types of supersymmetric left-right models, one with Higgs triplets and the other with both Higgs triplets as well as bitriplets. The minimal versions of these models do not give rise to the desired unification and some extra fields have to be added. After such a modification, i

  8. Travis Scrimshaw

    We explicitly construct an embedding of a right-angled Artin group into a classical pure braid group. Using this we obtain a number of corollaries describing embeddings of arbitrary Artin groups into right-angled Artin groups and linearly independent subgroups of a right-angled Artin group.

  9. Salvatore Torquato

    Theoretical and computational tools that can be used in the clinic to predict neoplastic progression and propose individualized optimal treatment strategies to control cancer growth is desired. To develop such a predictive model, one must account for the complex mechanisms involved in tumor growth. Here we review resarch work that we have done toward the dev

  10. Gordon Petrie, Aurelien Canou, Tahar Amari

    Between 2008/3/24 and 2008/4/2, the three active regions NOAA active regions 10987, 10988 and 10989 were observed daily by the Synoptic Optical Long-term Investigations of the Sun (SOLIS) Vector Spectro-Magnetograph (VSM) while they traversed the solar disk. We use these measurements and the nonlinear force-free magnetic field code XTRAPOL to reconstruct the

  11. Yerbol Khassen

    This work represents the final year project for BSc Physics with Astrophysics degree and it mainly focuses on empirical investigation of the photometry of quasars in the Sloan Digital Sky Survey (SDSS) and the UK Infrared Telescope (UKIRT) Infrared Sky Survey (UKIDSS) systems. The studies include 5730 quasars matched from both surveys and examine UV/optical/

  12. Kaya Tutuncuoglu, Aylin Yener

    Wireless networks with energy harvesting battery powered nodes are quickly emerging as a viable option for future wireless networks with extended lifetime. Equally important to their counterpart in the design of energy harvesting radios are the design principles that this new networking paradigm calls for. In particular, unlike wireless networks considered u

  13. Lucas Sourrouille

    We obtain by dimensional reduction a $(1+1)$ supersymmetric system introduced in the description of ultracold quantum gases. The correct supercharges are identified and their algebra is constructed. Finally novel static self-dual solutions emerge, satisfying a Liouville type differential equation.

  14. M. Jauregui, C. Tsallis

    A wide class of physical distributions appears to follow the q-Gaussian form, which plays the role of attractor according to a Central Limit Theorem generalized in the presence of specific correlations between the relevant random variables. In the realm of this theorem, a q-generalized Fourier transform plays an important role. We introduce here a method whi

  15. A. Di Piazza, A. I. Milstein, C. Müller

    The process of $e^+e^-$ production in the superposition of a Coulomb and a strong laser field is considered. The pair production rate integrated over the momentum and summed over the spin projections of one of the particles is derived exactly in the parameters of the laser field and in the Born approximation with respect to the Coulomb field. The case of a m

  16. Dmitri Antonov

    The correlation lengths of nonperturbative-nonconfining and confining stochastic background Yang-Mills fields are obtained by means of a direct analytic path-integral evaluation of the Green functions of the so-called one- and two-gluon gluelumps. Numerically, these lengths turn out to be in a good agreement with those known from the earlier, Hamiltonian, tr

  17. Juan A. Aguilar

    The IceCube Neutrino Observatory is a kilometer-scale detector currently under construction at the South Pole. The full detector will comprise 5,160 photomultipliers (PMTs) deployed on 86 strings from 1.45-2.45 km deep within the ice. As of the austral summer of 2009-10, 73 out of the total number strings have been deployed, and the detector is reaching its

  18. Song He, Tristan McLoughlin

    We study the relationship between the momentum twistor MHV vertex expansion of planar amplitudes in N=4 super-Yang-Mills and the all-loop generalization of the BCFW recursion relations. We demonstrate explicitly in several examples that the MHV vertex expressions for tree-level amplitudes and loop integrands satisfy the recursion relations. Furthermore, we i

  19. Maxim Lyutikov

    We calculate the evolution of the prompt intrinsic Poynting power generated by merging black holes. Orbiting black holes induce rotation of the space-time. In a presence of magnetic field supported by an accretion disk outside of the orbit, this results in a generation of an electromagnetic outflow via the Blandford-Znajek-type process with luminosity $L_{EM

  20. M. M. Bandi, T. Tallinen, L. Mahadevan

    A tenuous monolayer of hydrophobic particles at the air-water interface often forms a scum or raft. When such a monolayer is disturbed by the localized introduction of a surfactant droplet, a radially divergent surfactant shock front emanates from the surfactant origin and packs the particles into a jammed, compact, annular band with a packing fraction that

  21. F. Mackenroth, A. Di Piazza

    A detailed analysis of the photon emission spectra of an electron scattered by a laser pulse containing only very few cycles of the carrying electromagnetic field is presented. The analysis is performed in the framework of strong-field quantum electrodynamics, with the laser field taken into account exactly in the calculations. We consider different emission

  22. F. R. Ong, M. Boissonneault, F. Mallet, A. Palacios-Laloy

    We have performed spectroscopic measurements of a superconducting qubit dispersively coupled to a nonlinear resonator driven by a pump microwave field. Measurements of the qubit frequency shift provide a sensitive probe of the intracavity field, yielding a precise characterization of the resonator nonlinearity. The qubit linewidth has a complex dependence on

  23. Vadim A. Markel, John C. Schotland

    We consider the problem of homogenizing the Maxwell equations for periodic composites. The analysis is based on Bloch-Floquet theory. We calculate explicitly the reflection coefficient for a half-space, and derive and implement a computationally-efficient continued-fraction expansion for the effective permittivity. Our results are illustrated by numerical co

  24. I. A. Campbell, P. H. Lundow

    It is often assumed that for treating numerical (or experimental) data on continuous transitions the formal analysis derived from the Renormalization Group Theory can only be applied over a narrow temperature range, the "critical region"; outside this region correction terms proliferate rendering attempts to apply the formalism hopeless. This pessimi

  25. V. Leroy, A. L. Strybulevych, J. H. Page, M. G. Scanlon

    We present experimental results on a model system for studying wave propagation in a complex medium exhibiting low frequency resonances. These experiments enable us to investigate a fundamental question that is relevant for many materials, such as metamaterials, where low-frequency scattering resonances strongly influence the effective medium properties. Thi

  26. Alistair Hart, Georg von Hippel, R. R. Horgan, Andrew Lee

    We present the first two-loop calculation of the heavy quark energy shift in lattice nonrelativistic QCD (NRQCD). This calculation allow us to extract a preliminary prediction of $m_b(m_b, n_f = 5) = 4.25(12)$ GeV for the mass of the b quark from lattice NRQCD simulations performed with a lattice of spacing $a=0.12$fm. Our result is an improvement on a previ

  27. L. Malaquin, T. Charitat, J. Daillant, S. Lecuyer

    The interaction potential between supported floating bilayers has been determined by grazing incidence specular and off-specular scattering using synchrotron radiation. Our measurements demonstrate that floating bilayers are significantly more hydrated than the usually studied multilayers, therefore giving access to more intrinsic properties of the membranes

  28. Susana J. Landau, Florencia A. Teppa Pannia, Yuri Bonder, Daniel Sudarsky

    Seeking a possible explanation for recent data indicating a space-time variation of the electron-to-proton mass ratio within the Milky Way, we consider a phenomenological model where the effective fermion masses depend on the local value of the Weyl tensor. We contrast the required values of the model's free parameters with bounds obtained from modern te

  29. Leslie Ann Goldberg, Mark Jerrum

    We investigate the computational difficulty of approximating the partition function of the ferromagnetic Ising model on a regular matroid. Jerrum and Sinclair have shown that there is a fully polynomial randomised approximation scheme (FPRAS) for the class of graphic matroids. On the other hand, the authors have previously shown, subject to a complexity-theo

  30. Bernard J. Laurenzi

    Relations among integrals of logarithms, polylogarithms and Euler sums are presented. A unifying element being the introduction of Nielsen's generalized polylogarithms.

  31. Kenji Fukushima, Kazuhiko Kamikado, Bertram Klein

    We investigate phase transitions in scalar field theories using the functional renormalization group (RG) equation. We analyze a system with $U(2)\times U(2)$ symmetry, in which there is a parameter $\lambda_2$ that controls the strength of the first-order phase transition driven by fluctuations. In the limit of $\lambda_2\to0$, the $U(2)\times U(2)$ theory

  32. Gennady Mishuris, Alexander Movchan, Natasha Movchan, Andrea Piccolroaz

    The interaction of an interfacial crack with small impurities is analysed on the basis of an asymptotic formula derived by the authors. The interaction between the main crack and the defects (e.g. small cracks or inclusions) is described asymptotically by analysing the dipole fields and the corresponding dipole matrices of the defects in question. The method

  33. Mark Veraar

    In this paper we prove that a Gaussian white noise on the $d$-dimensional torus has paths in the Besov spaces $B^{-d/2}_{p,\infty}(\T^d)$ with $p\in [1, \infty)$. This result is shown to be optimal in several ways. We also show that Gaussian white noise on the $d$-dimensional torus has paths in a the Fourier-Besov space $\hat{b}^{-d/p}_{p,\infty}(\T^d)$. Thi

  34. D. R. Heath-Brown

    We show that there is a positive constant $c_0$ such that \[\sum_{n\le x}μ^2(n^2+1)c_0x+O_{\varepsilon}(x^{7/12+\varepsilon})\] for any fixed $\varepsilon>0$. This improves a result of Estermann [3] from 1931, in which the error term had an exponent 2/3. The proof involves counting rational points near an algebraic curve, which is done via the "determina

  35. Diego Marques, Jonathan Sondow

    We give a brief history of transcendental number theory, including Schanuel's conjecture (S). Assuming (S), we prove that if z and w are complex numbers, not 0 or 1, with z^w and w^z algebraic, then z and w are either both rational or both transcendental. A corollary is that if (S) is true, then we can find four distinct transcendental positive real numb

  36. Ioannis Z. Emiris, Guillaume Moroz

    Designing an m-bar linkage with a maximal number of assembly modes is important in robot kinematics, and has further applications in structural biology and computational geometry. A related question concerns the number of assembly modes of rigid mechanisms as a function of their nodes n, which is uniquely defined given m. Rigid 11-bar linkages, where n=7, ar

  37. Daniel Li

    It is known, from results of B. MacCluer and J. Shapiro (1986), that every composition operator which is compact on the Hardy space $H^p$, $1 \leq p < \infty$, is also compact on the Bergman space ${\mathfrak B}^p = L^p_a (\D)$. In this survey, after having described the above known results, we consider Hardy-Orlicz $H^Ψ$ and Bergman-Orlicz ${\mathfrak B}^Ψ$

  38. Masayoshi Kaneda

    We give a short proof of Belaga&#39;s result on bounds to perigees of $(3x+d)$-cycles of a given oddlength. We also reformulate the Collatz cycle conjecture which is rather a algorithmic problem into a purely arithmetic problem.

  39. Yuri Shtanov, Varun Sahni

    We generalize the cosmic energy equation to the case when massive particles interact via a modified gravitational potential of the form phi(a, r), which is allowed to explicitly depend upon the cosmological time through the expansion factor a(t). Using the nonrelativistic approximation for particle dynamics, we derive the equation for the cosmological expans

  40. P. Babkevich, B. Roessli, S. N. Gvasaliya, L. -P. Regnault

    We have used polarized-neutron inelastic scattering to resolve the spin fluctuations in superconducting FeSe0.5Te0.5 into components parallel and perpendicular to the layers. A spin resonance at an energy of 6.5 meV is observed to develop below T_c in both fluctuation components. The resonance peak is anisotropic, with the in-plane component slightly larger

  41. Ansgar Steland

    We consider the problem of bandwidth selection by cross-validation from a sequential point of view in a nonparametric regression model. Having in mind that in applications one often aims at estimation, prediction and change detection simultaneously, we investigate that approach for sequential kernel smoothers in order to base these tasks on a single statisti

  42. Bozena Czerny, Krzysztof Hryniewicz

    Although broad emission lines are the most reliable signature of the nuclear activity of a galaxy and the location of the emitting material is well measured by the reverberation method, the physical cause of the formation of the broad line region remains unclear. We attempt to place some constraints on its origin. We study the properties of the accretion dis

  43. Benjamin A. Burton, Melih Ozlen

    In low-dimensional topology, many important decision algorithms are based on normal surface enumeration, which is a form of vertex enumeration over a high-dimensional and highly degenerate polytope. Because this enumeration is subject to extra combinatorial constraints, the only practical algorithms to date have been variants of the classical double descript

  44. Ben Lowing, Adrian Jenkins, Vincent Eke, Carlos Frenk

    We apply a basis function expansion method to create a time-evolving density/potential approximation of the late growth of simulated N-body dark matter haloes. We demonstrate how the potential of a halo from the Aquarius Project can be accurately represented by a small number of basis functions, and show that the halo expansion (HEX) method provides a way to

  45. David Cook

    We introduce a new Macaulay2 package, Nauty, which gives access to powerful methods on graphs provided by the software nauty by Brendan McKay. The primary motivation for accessing nauty is to determine if two graphs are isomorphic. We also implement methods to generate families of graphs restricted in various ways using tools provided with the software nauty

  46. Stephen Fairhurst

    We derive an expression for the accuracy with which sources can be localized using a network of gravitational wave detectors. The result is obtained via triangulation, using timing accuracies at each detector and is applicable to a network with any number of detectors. We use this result to investigate the ability of advanced gravitational wave detector netw

  47. Pablo Soberón

    We will prove the following generalization of the ham sandwich Theorem, conjectured by Imre Bárány. Given a positive integer $k$ and $d$ nice measures $μ_1, μ_2,..., μ_d$ in $\mathbb{R}^d$ such that $μ_i (\mathds{R}^d) = k$ for all $i$, there is a partition of $\mathbb{R}^d$ in $k$ interior-disjoint convex parts $C_1, C_2,..., C_k$ such that $μ_i (C_j) = 1$

  48. A. del Campo, A. Retzker, M. B. Plenio

    The Kibble-Zurek mechanism is applied to the spontaneous formation of vortices in a harmonically trapped thermal gas following a temperature quench through the critical value for Bose-Einstein condensation. While in the homogeneous scenario vortex nucleation is always expected, we show that it can be completely suppressed in the presence of the confinement p

  49. Camilo Argoty

    We study the theory of a Hilbert space H as a module for a unital C*-algebra A from the point of view of continuous logic. We give an explicit axiomatization for this theory and describe the structure of all the representations which are elementary equivalent to it. We show that for every v in H the type of v over the empmtyset is in correspondence with the

  50. Constanze Liaw, Sergei Treil

    In the theory of singular integral operators significant effort is often required to rigorously define such an operator. This is due to the fact that the kernels of such operators are not locally integrable on the diagonal, so the integral formally defining the operator or its bilinear form is not well defined (the integrand is not in L^1) even for nice func

  51. P. P. Goldstein, A. M. Grundland

    We study certain new properties of 2D surfaces associated with the $\mathbb{C}P^{N-1}$ models and the wave functions of the corresponding linear spectral problem. We show that $su(N)$-valued immersion functions expressed in terms of rank-1 orthogonal projectors are linearly dependent, but they span an $(N-1)$-dimensional subspace of the Lie algebra $su(N)$.

  52. Simon Candelaresi, Alexander Hubbard, Axel Brandenburg, Dhrubaditya Mitra

    Magnetic helicity fluxes are investigated in a family of gauges in which the contribution from ideal magnetohydrodynamics takes the form of a purely advective flux. Numerical simulations of magnetohydrodynamic turbulence in this advective gauge family exhibit instabilities triggered by the build-up of unphysical irrotational contributions to the magnetic vec

  53. Dan Abramovich, Jan Denef, Kalle Karu

    We prove that any dominant morphism of algebraic varieties over a field k of characteristic zero can be transformed into a toroidal (hence monomial) morphism by projective birational modifications of source and target. This was previously proved by the first and third author when k is algebraically closed. Moreover we show that certain additional requirement

  54. Xavier De Scheemaekere

    This paper establishes a converse comparison theorem for real-valued decoupled forward backward stochastic differential equations with jumps.

  55. P. L. de Andres, A. Guijarro, J. A. Verges

    The crystal structure of potassium doped picene with an exact stoichiometry (K3C22H14, K3picene from here onwards) has been theoretically determined within Density Functional Theory allowing complete variational freedom of the crystal structure parameters and the molecular atomic positions. A modified herringbone lattice is obtained in which potassium atoms

  56. Ju-Jun Xie, A. Martínez Torres, E. Oset

    We perform a calculation for the three body $N \bar{K} K$ scattering amplitude by using the fixed center approximation to the Faddeev equations, taking the interaction between $N$ and $\bar{K}$, $N$ and $K$, and $\bar{K}$ and $K$ from the chiral unitary approach. The resonant structures show up in the modulus squared of the three body scattering amplitude an

  57. K. Chetyrkin, J. H. Kühn, A. Maier, P. Maierhöfer

    Recent theoretical and experimental improvements in the determination of charm and bottom quark masses are discussed. A new and improved evaluation of the contribution from the gluon condensate $< \frac{α_s}π G^2>$ to the charm mass determination and a detailed study of potential uncertainties in the continuum cross section for $b\bar b$ production is presen

  58. Riccardo Messina, Ruggero Vasile, Roberto Passante

    We study the time evolution of the Casimir-Polder force acting on a neutral atom in front of a perfectly conducting plate, when the system starts its unitary evolution from a partially dressed state. We solve the Heisenberg equations for both atomic and field quantum operators, exploiting a series expansion with respect to the electric charge and an iterativ

  59. Molin Liu, Junwang Lu, Benhai Yu, Jianbo Lu

    In this paper, we study the motion of photons around a Kehagias-Sfetsos (KS) black hole and obtain constraints on IR modified Ho$\check{r}$ava gravity without cosmological constant ($\sim Λ_{W}$). An analytic formula for the light deflection angle is obtained. For a propagating photon, the deflection angle $δϕ$ increases with large values of the Ho$\check{r}

  60. Ying Tang, Anders W. Sandvik, Christopher L. Henley

    We use Monte Carlo simulations to study properties of Anderson&#39;s resonating-valence-bond (RVB) spin-liquid state on the square lattice (i.e., the equal superposition of all pairing of spins into nearest-neighbor singlet pairs) and compare with the classical dimer model (CDM). The latter system also corresponds to the ground state of the Rokhsar-Kivelson

  61. Tri Thanh Pham, Burkhard Duenweg, J. Ravi Prakash

    We investigate the dynamics of the collapse of a single copolymer chain, when the solvent quality is suddenly quenched from good to poor. We employ Brownian dynamics simulations of a bead-spring chain model and incorporate fluctuating hydrodynamic interactions via the Rotne-Prager-Yamakawa tensor. Various copolymer architectures are studied within the framew

  62. Mats Andersson, Håkan Samuelsson

    Let $X$ be a complex space of pure dimension. We introduce fine sheaves $\A^X_q$ of $(0,q)$-currents, which coincides with the sheaves of smooth forms on the regular part of $X$, so that the associated Dolbeault complex yields a resolution of the structure sheaf $\hol^X$. Our construction is based on intrinsic and quite explicit semi-global Koppelman formula

  63. Pengbo Li, Shaoyan Gao, Fuli Li

    We propose an efficient scheme for the realization of quantum information transfer and entanglement with nitrogen-vacancy (NV) centers coupled to a high-Q whispering-gallery mode (WGM) microresonator. We show that, based on the effective dipole-dipole interaction between the NV centers mediated by the WGM, quantum information can be transferred between the N

  64. Dionys Baeriswyl

    The two-dimensional repulsive Hubbard model has been investigated by a variety of methods, from small to large U. Superconductivity with d-wave symmetry is consistently found close to half filling. After a brief review of the various methods a variational many-electron state is discussed in more detail. This trial state is a natural extension of the Gutzwill

  65. Yutaka Hosotani, Minoru Tanaka, Nobuhiro Uekusa

    In the SO(5) x U(1) gauge-Higgs unification model in the Randall-Sundrum warped space there results the conservation of the H parity. The H parity is assigned to all 4D fields including excited modes in Kaluza-Klein towers. The neutral Higgs boson is the lightest particle of odd H parity, consequently becoming absolutely stable. Its mass is found to be 70 \s

  66. Masafumi Udagawa, Youichi Yanase

    We have studied the effects of electron correlation on Van Vleck susceptibility ($χ_{\rm{VV}}$) in transition metal compounds. A typical crossover behavior is found for the correlation effect on $χ_{\rm{VV}}$ as sweeping spin-orbit interaction, $λ$. For a small $λ$, orbital fluctuation plays a dominant role in the correlation enhancement of $χ_{\rm{VV}}$; ho

  67. Jong Phil Lee, Kang Young Lee

    We show that the recently measured 3.2 $σ$ deviations of the charge asymmetry of like-sign dimuon events from the standard model prediction by the D0 collaboration at Tevatron can be explained by introducing the anomalous right-handed top quark couplings. Combined analysis with the $\bs$ and $\bd$ mixings and $B \to X_s γ$ decays has been performed. We discu

  68. Tomoya Hayata

    A non-perturbative method which can go beyond the weak coupling perturbation theory is introduced. Essential idea is to formulate a set of exact differential equations as a function of the coupling strength $g$. Unlike other resummation in which information of the higher order terms is necessary, we only need a leading order perturbative formula in every ste

  69. Jingchen Liu, Gongjun Xu, Zhiliang Ying

    Cognitive assessment is a growing area in psychological and educational measurement, where tests are given to assess mastery/deficiency of attributes or skills. A key issue is the correct identification of attributes associated with items in a test. In this paper, we set up a mathematical framework under which theoretical properties may be discussed. We esta

  70. Mahir Bilen Can, Roger Howe, Michael Joyce

    We investigate the topology of the closure in a wonderful compactification of the set of unipotent-invariant bilinear forms.

  71. Vanja Dukic, Nevena Maric

    In this paper we present a method for exact generation of multivariate samples with pre-specified marginal distributions and a given correlation matrix, based on a mixture of Fréchet-Hoeffding bounds and marginal products. The bivariate algorithm can accommodate any among the theoretically possible correlation coefficients, and explicitly provides a connecti

  72. R. N. Lee, I. S. Terekhov

    We apply the DRA method to the calculation of the four-loop `QED-type&#39; tadpoles. For arbitrary space-time dimensionality D the results have the form of multiple convergent sums. We use these results to obtain the epsilon-expansion of the integrals around D=3 and D=4.

  73. Yan He, Weimin Sheng

    In this paper we consider Yamabe type problem for higher order curvatures on manifolds with totally geodesic boundaries. We prove local gradient and second derivative estimates for solutions to the fully nonlinear elliptic equations associated with the problems.

  74. K. Iida, S. Haindl, T. Thersleff, J. Haenishc

    The implementation of an Fe buffer layer is a promising way to obtain epitaxial growth of Co-doped BaFe2As2 (Ba-122). However, the crystalline quality and the superconducting properties of Co-doped Ba-122 are influenced by the Fe buffer layer thickness, dFe. The well-textured growth of the Fe/Ba-122 bilayer with dFe = 15 nm results in a high Jc of 0.45 MAcm$

  75. L. A. Tracy, E. P. Nordberg, R. W. Young, C. Borras Pinilla

    We present transport measurements of a tunable silicon metal-oxide-semiconductor double quantum dot device with lateral geometry. Experimentally extracted gate-to-dot capacitances show that the device is largely symmetric under the gate voltages applied. Intriguingly, these gate voltages themselves are not symmetric. Comparison with numerical simulations ind

  76. Guillaume Roux

    In his Comment [see preceding Comment, Phys. Rev. A 82, 037601 (2010)] on the paper by Roux [Phys. Rev. A 79, 021608(R) (2009)], Rigol argued that the energy distribution after a quench is not related to standard statistical ensembles and cannot explain thermalization. The latter is proposed to stem from what he calls the eigenstate thermalization hypothesis

  77. Hao Xu, Hui Li, David C. Collins, Shengtai Li

    We present a series of cosmological magnetohydrodynamic (MHD) simulations that simultaneously follow the formation of a galaxy cluster and evolution of magnetic fields ejected by an Active Galactic Nucleus (AGN). Specifically, we investigate the influence of both the epoch of AGN (z $\sim$ 3-0.5) and the AGN energy ($\sim$ 3 $\times$ 10$^{57}$ - 2 $\times$ 1

  78. B. Gutkin, V. Al. Osipov

    The spectral problem for matrices with a block-hierarchical structure is often considered in context of the theory of complex systems. In the present article, a new class of matrices with a block-rectangular non-symmetric hierarchical structure is introduced and the corresponding spectral problem is investigated. Using these results we study a model of error

  79. Paweł Konieczny, Ondřej Kreml

    We study steady flow of a second grade fluid past an obstacle in three space dimensions. We prove existence of solution in weighted Lebesgue spaces with anisotropic weights and thus existence of the wake region behind the obstacle. We use properties of the fundamental Oseen tensor together with results achieved in \cite{Koch} and properties of solutions to s

  80. Ronald Babich, Michael A. Clark, Bálint Joó

    Graphics Processing Units (GPUs) are having a transformational effect on numerical lattice quantum chromodynamics (LQCD) calculations of importance in nuclear and particle physics. The QUDA library provides a package of mixed precision sparse matrix linear solvers for LQCD applications, supporting single GPUs based on NVIDIA&#39;s Compute Unified Device Arch

  81. Piet Groeneboom

    We derive a simple integral representation for the distribution of the maximum of Brownian motion minus a parabola, which can be used for computing the density and moments of the distribution, both for one-sided and two-sided Brownian motion.

  82. Ian Biringer, Jesse Johnson, Yair Minsky

    We show that a pseudo-Anosov map on a boundary component of an irreducible 3-manifold has a power that partially extends to the interior if and only if its (un)stable lamination is a projective limit of meridians. The proof is through 3-dimensional hyperbolic geometry, and involves an investigation of algebraic limits of convex cocompact compression bodies.

  83. Haifeng Ma, Thomas Greber

    A measure for the description of the chirality of triangles is introduced. The measure $Xδ$ is zero for triangles with at least one mirror axe, i.e. equilateral or isosceles triangles, and positive or negative for scalane, i.e. left or right handed triangles, respectively.

  84. H. Peelaers, A. D. Hernández-Nieves, O. Leenaerts, B. Partoens

    The vibrational properties of graphene fluoride and graphane are studied using ab initio calculations. We find that both sp3 bonded derivatives of graphene have different phonon dispersion relations and phonon density of states as expected from the different masses associated with the attached atoms fluorine and hydrogen, respectively. These differences mani

  85. George B. Trammell, Phil Arras, Zhi-Yun Li

    (Abridged) The upper atmospheres of close-in gas giant exoplanets are subjected to intense heating/tidal forces from their parent stars. Atomic/ionized hydrogen (H) layers are sufficiently rarefied that magnetic pressure may dominate gas pressure for expected planetary magnetic field strength. We examine the magnetospheric structure using a 3D isothermal mag

  86. James Nolen, Alexei Novikov

    We study the homogenization limit of solutions to the G-equation with random drift. This Hamilton-Jacobi equation is a model for flame propagation in a turbulent fluid in the regime of thin flames. For a fluid velocity field that is statistically stationary and ergodic, we prove sufficient conditions for homogenization to hold with probability one. These con

  87. Baruch Barzel, Ofer Biham

    A highly efficient formulation of moment equations for stochastic reaction networks is introduced. It is based on a set of binomial moments that capture the combinatorics of the reaction processes. The resulting set of equations can be easily runcated to include moments up to any desired order. The number of equations is dramatically reduced compared to the

  88. W. -H. Hsu, M. E. Putman, F. Heitsch, S. Stanimirovic

    Observations from the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) Survey of the tail of Complex C are presented and the halo clouds associated with this complex cataloged. The properties of the Complex C clouds are compared to clouds cataloged at the tail of the Magellanic Stream to provide insight into the origin and destruction mechanism of Complex C.

  89. G. C. Bento, O. P. Ferreira, P. R. Oliveira

    In this paper we present a steepest descent method with Armijo&#39;s rule for multicriteria optimization in the Riemannian context. The well definedness of the sequence generated by the method is guaranteed. Under mild assumptions on the multicriteria function, we prove that each accumulation point (if they exist) satisfies first-order necessary conditions f

  90. V. S. Titov, Z. Mikic, J. A. Linker, R. Lionello

    In recent work, Antiochos and coworkers argued that the boundary between the open and closed field regions on the Sun can be extremely complex with narrow corridors of open flux connecting seemingly disconnected coronal holes from the main polar holes, and that these corridors may be the sources of the slow solar wind. We examine, in detail, the topology of

  91. M. Cvetic, G. W. Gibbons, C. N. Pope

    We present explicit results for the product of all horizon areas for general rotating multi-charge black holes, both in asymptotically flat and asymptotically anti-de Sitter spacetimes in four and higher dimensions. The expressions are universal, and depend only on the quantized charges, quantized angular momenta and the cosmological constant. If the latter

  92. Hideo Suganuma, Takumi Iritani, Arata Yamamoto, Hideaki Iida

    We study the gluon propagator in the Landau gauge in SU(3) lattice QCD at $β$=5.7, 5.8 and 6.0 at the quenched level. The Euclidean Landau-gauge gluon propagator $D(r)\equiv D_{μμ}^{aa}(x)/24$ is found to be well described by four-dimensional Yukawa-type function $e^{-mr}/r$ in the infrared and intermediate region of $r \equiv (x_μx_μ)^{1/2}$ = 0.1 $\sim$ 1.

  93. Christian D. Ott, Evan O&#39;Connor

    We discuss results from simulations of black hole formation in failing core-collapse supernovae performed with the code GR1D, a new open-source Eulerian spherically-symmetric general-relativistic hydrodynamics code. GR1D includes rotation in an approximate way (1.5D), comes with multiple finite-temperature nuclear equations of state (EOS), and treats neutrin

  94. Keith Bannister, Tara Murphy, Bryan M. Gaensler, Richard Hunstead

    We describe a 22-year survey for variable and transient radio sources, performed with archival images taken with the Molonglo Observatory Synthesis Telescope (MOST). This survey covers $2775 \unit{deg^2}$ of the sky south of $δ< -30\degree$ at an observing frequency of 843 MHz, an angular resolution of $45 \times 45 \csc | δ| \unit{arcsec^2}$ and a sensitivi

  95. A. Sollima, D. Martinez-Delgado, D. Valls-Gabaud, J. Penarrubia

    We report the detection of a pair of degree-long tidal tails associated with the globular cluster Palomar 14, using images obtained at the CFHT. We reveal a power-law departure from a King profile at large distances to the cluster center. The density map constructed with the optimal matched filter technique shows a nearly symmetrical and elongated distributi

  96. Stefan Walter

    We determine the critical coupling of the two-dimensional Brown-Ravenhall operator with Coulomb potential. Boundedness from below has essentially been proven by Bouzouina, whose work however contains a trivial error leading to a wrong constant exactly one half of the actual critical constant. Furthermore we show that the operator is in fact positive. Our pro

  97. M. S. Onegin

    The burn-up for SC56-1472 sample of the natural Oklo reactor zone 3 was calculated using the modern Monte Carlo codes. We reconstructed the neutron spectrum in the core by means of the isotope ratios: $^{147}$Sm/$^{148}$Sm and $^{176}$Lu/$^{175}$Lu. These ratios unambiguously determine the spectrum index and core temperature. The effective neutron absorption

  98. Boris Shapiro

    The purpose of this short paper is to recall the theory of the (homogenized) spectral problem for a Schroedinger equation with a polynomial potential developed in the 60&#39;s by M. Evgrafov with M. Fedoryuk, and, by Y. Sibuya and its relation with quadratic differentials. We derive from these results that the accumulation rays of the eigenvalues of this pro

  99. Etienne Marcotte, Frank H. Stillinger, Salvatore Torquato

    We have previously used inverse statistical-mechanical methods to optimize isotropic pair interactions with multiple extrema to yield low-coordinated crystal classical ground states (e.g., honeycomb and diamond structures) in d-dimensional Euclidean space R^d. Here we demonstrate the counterintuitive result that no extrema are required to produce such low-co

  100. M Saffman, X L Zhang, A T Gill, L Isenhower

    Experiments performed within the last year have demonstrated Rydberg state mediated quantum gates and deterministic entanglement between pairs of trapped neutral atoms. These experiments validate ten year old proposals for Rydberg mediated quantum logic, but are only the beginning of ongoing efforts to improve the fidelity of the results obtained and scale t