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July 2006 arXiv papers — page 43

Showing 4,2014,300 of 4,443 papers

  1. D. M. Schröer, A. K. Hüttel, K. Eberl, S. Ludwig

    We present transport measurements of the Kondo effect in a double quantum dot charged with only one or two electrons, respectively. For the one electron case we observe a surprising quasi-periodic oscillation of the Kondo conductance as a function of a small perpendicular magnetic field |B| \lesssim 50mT. We discuss possible explanations of this effect and i

  2. V. Janis, P. Augustinsky

    We present an analytic universal impurity solver for strongly correlated electrons. We extend the many-body perturbation expansion via suitable two-particle renormalizations from the Fermi-liquid regime to the critical region of the metal-insulator transition. The reliability of the approximation in the strong-coupling limit is demonstrated by reproducing th

  3. Shunsuke Furukawa, Gregoire Misguich, Masaki Oshikawa

    Resonating valence bond (RVB) liquids in two dimensions are believed to exhibit topological order and to admit no local order parameter of any kind. This is a defining property of "liquids" but it has been explicitly confirmed only in a few exactly solvable models. In this paper, we investigate the quantum dimer model on the triangular lattice. It po

  4. Zhi-Guang Xiao, Gang Yang, Chuan-Jie Zhu

    The rational parts of 6-gluon one-loop amplitudes with scalars circulating in the loop are computed by using the newly developed method for computing the rational parts directly from Feynman integrals. We present the analytic results for the two MHV helicity configurations: $(1^-2^+3^+4^-5^+6^+)$ and $(1^-2^+3^-4^+5^+6^+)$, and the two NMHV helicity configur

  5. Xun Su, Zhi-Guang Xiao, Gang Yang, Chuan-Jie Zhu

    The rational parts of 5-gluon one-loop amplitudes are computed by using the newly developed method for computing the rational parts directly from Feynman integrals. We found complete agreement with the previously well-known results of Bern, Dixon and Kosower obtained by using the string theory method. Intermediate results for some combinations of Feynman dia

  6. W. G. D. Dharmaratna, V. Hagopian, K. F. Johnson, J. McDonald

    This paper has been withdrawn because it has not been vetted by CMS

  7. Derek McHugh, Mario Ziman, Vladimir Buzek

    We study the relationship between the entanglement, mixedness and energy of two-qubit and two-mode Gaussian quantum states. We parametrize the set of allowed states of these two fundamentally different physical systems using measures of entanglement, mixedness and energy that allow us to compare and contrast the two systems using a phase diagram. This phase

  8. M. Caselle, P. Grinza, N. Magnoli

    We study the flux tube thickness in the confining phase of the (2+1)d SU(2) Lattice Gauge Theory near the deconfining phase transition. Following the Svetitsky-Yaffe conjecture, we map the problem to the study of the <epsilon sigma sigma> correlation function in the two-dimensional spin model with Z_2 global symmetry, (i.e. the 2d Ising model) in the high-te

  9. Marie-Catherine Desjonqueres, Cyrille Barreteau, Gabriel Autes, Daniel Spanjaard

    We show that considerable orbital magnetic moments and magneto-crystalline anisotropy energies are obtained for a Fe monatomic wire described in a tight-binding method with intra-atomic electronic interactions treated in a full Hartree Fock (HF) decoupling scheme. Even-though the use of the orbital polarization ansatz with simplified Hamiltonians leads to fa

  10. B. I. Ermolaev, M. Greco, S. I. Troyan

    We prove that regulating infrared divergencies generates power (~1/(Q^2)^k) corrections to the spin structure function g_1 at small x and large Q^2. At the same time it leads to the corrections ~(Q^2)^k at small Q^2. We present the explicit series of such terms as well as the formulae for their resummation. These contributions are not included in the standar

  11. Clair Poignard

    We study the behavior of steady state voltage potentials in two kinds of bidimensional media composed of material of complex permittivity equal to 1 (respectively $α$) surrounded by a thin membrane of thickness $h$ and of complex permittivity $α$ (respectively 1). We provide in both cases a rigorous derivation of the asymptotic expansion of steady state volt

  12. Wei Wang, Jinqiao Duan

    Random invariant manifolds often provide geometric structures for understanding stochastic dynamics. In this paper, a dynamical approximation estimate is derived for a class of stochastic partial differential equations, by showing that the random invariant manifold is almost surely asymptotically complete. The asymptotic dynamical behavior is thus described

  13. E. Ferrero, S. J. Wagner, D. Emmanoulopoulos, L. Ostorero

    The possibility to detect simultaneously in the X-ray band the synchrotron and Inverse Compton (IC)emission of intermediate BL Lac objects offers the unique opportunity to study contemporaneously the low- and high-energy tails of the electron distribution in the jets of these sources. We attempted to disentangle the X-ray spectral variability properties of b

  14. M. Kampakoglou, A. J. Benson

    We examine the problem tidally-induced mass loss from collisionless systems such as dark matter haloes. We develop a model for tidal mass loss, based upon the phase space distribution of particles, which accounts for how both tidal and Coriolis torques perturb the angular momentum of each particle in the system. This allows us to study how both the density p

  15. M. W. J. Romans, H. T. C. Stoof

    We present the Bogoliubov theory for the Bose-Einstein condensation of Feshbach molecules in a balanced Fermi mixture. Because the Bogoliubov theory includes (Gaussian) fluctuations, we can in this manner accurately incorporate both the two-body and many-body aspects of the BEC-BCS crossover that occurs near a Feshbach resonance. We apply the theory in parti

  16. J. I. Vestgarden, D. V. Shantsev, A. A. F. Olsen, Y. M. Galperin

    Interaction between a Bloch wall in a ferrite-garnet film and a vortex in a superconductor is analyzed in the London approximation. Equilibrium distribution of vortices formed around the Bloch wall is calculated. The results agree quantitatively with magneto-optical experiment where an in-plane magnetized ferrite-garnet film placed on top of NbSe2 supercondu

  17. G. Puentes, D. Voigt, A. Aiello, J. P. Woerdman

    We report experimental results on mixed-state generation by multiple scattering of polarization-entangled photon pairs created from parametric down-conversion. By using a large variety of scattering optical systems we have experimentally obtained entangled mixed states that lie upon and below the Werner curve in the linear entropy-tangle plane. We have also

  18. N. Nakai, P. Miranovic, M. Ichioka, H. F. Hess

    It is demonstrated theoretically and experimentally that the low energy density of states $N(E)$ is described by a singular V-shape form $N(E)=N_0(H)+α|E|+O(E^2)$ for all clean superconductors in a vortex state, irrespective of the underlying gap structure. The linear term $α|E|$ which has been not recognized so far is obtained by exactly evaluating the vort

  19. S. Antusch, C. Biggio, E. Fernandez-Martinez, M. B. Gavela

    We determine the elements of the leptonic mixing matrix, without assuming unitarity, combining data from neutrino oscillation experiments and weak decays. To that end, we first develop a formalism for studying neutrino oscillations in vacuum and matter when the leptonic mixing matrix is not unitary. To be conservative, only three light neutrino species are c

  20. Michel Granger, David Mond, Alicia Nieto-Reyes, Mathias Schulze

    A complex hypersurface D in complex affine n-space C^n is a linear free divisor (LFD) if its module of logarithmic vector fields has a global basis of linear vector fields. We classify all LFDs for n at most 4. Analogous to Grothendieck&#39;s comparison theorem, we say that the global logarithmic comparison theorem (GLCT) holds for D if the complex of global

  21. Stanislav Babak, Hua Fang, Jonathan R. Gair, Kostas Glampedakis

    One of the most exciting potential sources of gravitational waves for low-frequency, space-based gravitational wave (GW) detectors such as the proposed Laser Interferometer Space Antenna (LISA) is the inspiral of compact objects into massive black holes in the centers of galaxies. The detection of waves from such &#34;extreme mass ratio inspiral&#34; systems

  22. Orfeu Bertolami

    We discuss how developments in physics often imply in the need that spacetime acquires an increasingly richer and complex structure. General Relativity was the first theory to show us the way to connect space and time with the physical world. Since then, scrutinizing the ways spacetime might exist is, in a way, the very essence of physics. Physics has thus g

  23. Peter Orland

    We generalize the (2+1)-dimensional Yang-Mills theory to an anisotropic form with two gauge coupling constants $e$ and $e^{\prime}$. In an axial gauge, a regularized version of the Hamiltonian of this gauge theory is $H_{0}+{e^{\prime}}^{2}H_{1}$, where $H_{0}$ is the Hamiltonian of a set of (1+1)-dimensional principal chiral nonlinear sigma models. We treat

  24. S. Mignemi

    We study the phase space of the spherically symmetric solutions of the system obtained from the dimensional reduction of the six-dimensional Einstein-Gauss- Bonnet action. We show the existence of solutions with nonflat asymptotic behavior.

  25. I. Weymann, J. Barnas

    Spin-dependent transport through a two-level quantum dot in the sequential tunneling regime is analyzed theoretically by means of a real-time diagrammatic technique. It is shown that the current, tunnel magnetoresistance, and shot noise (Fano factor) strongly depend on the transport regime, providing a detailed information on the electronic structure of quan

  26. G. Nanava, Z. Was

    Recently, QED bremsstrahlung in $B$-meson decays into pair of scalars (π&#39;s and/or K&#39;s) is of interest. If experimental acceptance must be taken into account, PHOTOS Monte Carlo is often used in experimental simulations. We will use scalar QED to benchmark PHOTOS, even though this theory is of limited use for complex objects. We present the analytical

  27. D. Kechrakos, K. N. Trohidou

    We present Monte Carlo simulations of the reversible transverse susceptibility (RTS) for a hexagonal array of dipolar interacting magnetic nanoparticles with random anisotropy. RTS curves with the bias-field in-plane and out-of-plane are compared. With increasing temperature the RTS curves evolve from a three-peak structure to a double-peak and eventually a

  28. Jean-Marc Azaïs Mario Wschebor

    We study the probability distribution $F(u)$ of the maximum of smooth Gaussian fields defined on compact subsets of $\R^d$ having some geometric regularity. Our main result is a general formula for the density of $F$. Even though this is an implicit formula, one can deduce from it explicit bounds for the density, hence for the distribution, as well as improv

  29. Makoto Nakamura, Takeshi Wada

    The time local and global well-posedness for the Maxwell-Schr{\"o}dinger equations is considered in Sobolev spaces in three spatial dimensions. The Strichartz estimates of Koch and Tzvetkov type are used for obtaining the solutions in the Sobolev spaces of low regularities. One of the main results is that the solutions exist time globally for large data.

  30. Ashley Montanaro

    We develop two analytic lower bounds on the probability of success p of identifying a state picked from a known ensemble of pure states: a bound based on the pairwise inner products of the states, and a bound based on the eigenvalues of their Gram matrix. We use the latter to lower bound the asymptotic distinguishability of ensembles of n random quantum stat

  31. Cedric Lecouvey

    We use power sums plethysm operators to introduce H functions which interpolate between the Weyl characters and the Hall-Littlewood functions Q&#39; corresponding to classical Lie groups. The coefficients of these functions on the basis of Weyl characters are parabolic Kazhdan-Lusztig polynomials and thus, are nonnegative. We prove that they can be regarded

  32. Steen A. Andersson, Michael D. Perlman

    Chain graphs (CG) use undirected and directed edges to represent both structural and associative dependences. Like acyclic directed graphs (ADGs), the CG associated with a statistical Markov model may not be unique, so CGs fall into Markov equivalence classes, which may be superexponentially large, leading to unidentifiability and computational inefficiency

  33. Y. Maeda, M. Hartmann, I. Keshelashvili, S. Barsov

    The quasi-free pn->dphi reaction has been studied at the Cooler Synchrotron COSY-Juelich, using the internal proton beam incident on a deuterium cluster-jet target and detecting a fast deuteron in coincidence with the K+K- decay of the phi-meson. The energy dependence of the total and differential cross sections are extracted for excess energies up to 80 MeV

  34. Yasunori Mawatari, John R. Clem

    We theoretically investigate the response of a superconducting film to line currents flowing in linear wires placed above the film, and we present analytic expressions for the magnetic-field and current distributions based on the critical state model. The behavior of the superconducting film is characterized by the sheet-current density $K_z$, whose magnitud

  35. Elena Chierici, Gianluca Occhetta

    We classify Fano fivefolds of index two which are blow-ups of smooth manifolds along a smooth center.

  36. W. S. Choi, S. S. A. Seo, K. W. Kim, T. W. Noh

    We investigated the dielectric functions $ε$($ω$) of Ir, Ru, Pt, and IrO$_2$, which are commonly used as electrodes in ferroelectric thin film applications. In particular, we investigated the contributions from bound charges $ε^{b}$($ω$), since these are important scientifically as well as technologically: the $ε_1^{b}$(0) of a metal electrode is one of the

  37. Masahito Hayashi

    This paper has been withdrawn by the author because Lemma 3 is incorrect. This mistake is crucial in this paper.

  38. Masahito Hayashi

    This paper has been withdrawn by the author because Lemma 3 is incorrect. This mistake is crucial in this paper.

  39. S. J. Moon, M. W. Kim, K. W. Kim, Y. S. Lee

    We investigated the electronic structures of the two-dimensional layered perovskite Sr$_{2}$\textit{M}O$_{4}$ (\textit{M}=4\textit{d} Ru, 4\textit{d} Rh, and 5\textit{d} Ir) using optical spectroscopy and polarization-dependent O 1\textit{s} x-ray absorption spectroscopy. While the ground states of the series of compounds are rather different, their optical

  40. Boris D. Lubachevsky

    In 1960s V.Geodakian proposed a theory that explains sexes as a mechanism for evolutionary adaptation of the species to changing environmental conditions. In 2001 V.Iskrin refined and augmented the concepts of Geodakian and gave a new and interesting explanation to several phenomena which involve sex, and sex ratio, including the war-years phenomena. He also

  41. Shellie Huether, Ryan Kinney, Thomas Vojta

    We investigate a model for randomly layered magnets, viz. a three-dimensional Ising model with planar defects. The magnetic phase transition in this system is smeared because static long-range order can develop on isolated rare spatial regions. Here, we report large-scale kinetic Monte Carlo simulations of the dynamical behavior close to the smeared phase tr

  42. Spyros Efthimiades

    The wavefunction of a particle is obtained from its intermediate states and interaction processes considered as happening concurrently. When the interaction is described by a potential, the energy of the particle is equal to its total kinetic plus potential energies. We derive the Schrodinger and Dirac equations as the unique conditions the wavefunction must

  43. Gursoy B. Akguc, Thomas H. Seligman

    We present an efficient method to solve scattering problems in two-dimensional open billiards with two leads and a complicated scattering region. The basic idea is to transform the scattering region to a rectangle, which will lead to complicated dynamics in the interior, but simple boundary conditions. The method can be specialized to closed billiards, and i

  44. Emanuel Knill, Gerardo Ortiz, Rolando D. Somma

    Experimental characterizations of a quantum system involve the measurement of expectation values of observables for a preparable state |psi> of the quantum system. Such expectation values can be measured by repeatedly preparing |psi> and coupling the system to an apparatus. For this method, the precision of the measured value scales as 1/sqrt(N) for N repeti

  45. Julien Chabé, Hans Lignier, Hugo L. D. De Souza Cavalcante, Dominique Delande

    We study the destruction of dynamical localization, experimentally observed in an atomic realization of the kicked rotor, by a deterministic Hamiltonian perturbation, with a temporal periodicity incommensurate with the principal driving. We show that the destruction is gradual, with well defined scaling laws for the various classical and quantum parameters,

  46. Paolo Amore, Francisco Fernandez

    We develop a perturbation method that generalizes an approach proposed recently to treat velocity--dependent quantum--mechanical models. In order to test present approach we apply it to some simple trivial and nontrivial examples.

  47. P. O. Andrade, R. A. Bitar, K. Yassoyama, H. Martinho

    FT-Raman spectroscopy was employed to study (in-vitro) non-altered human colorectal tissues aiming evaluate their spectral differences. The samples were collected from 39 patients, adding 144 spectra. The results enable one estabilish 3 well defined spectroscopic groups of what was consistently checked by statistical (clustering) and biological (histopatholo

  48. A. V. Lyashenko, A. Breskin, R. Chechik, J. F. C. A. Veloso

    A new concept is presented for the reduction of ion back-flow in GEM-based cascaded gaseous electron multipliers, by incorporating Micro-Hole & Strip Plate (MHSP) elements operating in reversed-bias mode (R-MHSP). About an order of magnitude reduction in ion back-flow is achieved by diverting back-drifting ions from their original path. A R-MHSP/2GEM/MHSP ca

  49. Randall D. Peters

    Numerous different experiments by the author, approaching nearly two decades of study, point strongly toward the possibility that friction operates around a mesoscale quantum of energy having the value 11 pJ.

  50. Andre Almeida, Christophe Vergez, René Caussé

    This article proposes a characterisation of the double-reed in quasi-static regimes. The non-linear relation between the pressure drop $Δp$ in the double-reed and the volume flow crossing it $q$ is measured for slow variations of these variables. The volume flow is determined from the pressure drop in a diaphragm replacing the instrument&#39;s bore. Measurem

  51. Jean-Paul Giovanangeli, Christian Kharif, Efim Pelinovski

    One of the popular machanisms of the freak waves phenomenon is the dispersive focusing of transient wave groups. In all published theoretical and experimental papers the surface gravity waves are considered as an ensemble of free waves. This paper reports on a series of experiments conducted in the large wind-wave tank od IRPHE to study the wind effect on th

  52. V. A. Maisheev

    The analytical description of the volume reflection of the charged ultrarelativistic particles in bent single crystals is considered. The relation describing the angle of volume reflection as a function of the transversal energy is obtained. The different angle distributions of the scattered protons in the single crystals are found. Results of calculations f

  53. J. R. Stone, P. -G. Reinhard

    Self-consistent mean-field models are a powerful tool in the investigation of nuclear structure and low-energy dynamics. They are based on effective energy-density functionals, often formulated in terms of effective density-dependent nucleon-nucleon interactions. The free parameters of the functional are adjusted to empirical data. A proper choice of these p

  54. St. Kistryn, E. Stephan, B. Klos, A. Biegun

    High precision cross-section data of the deuteron-proton breakup reaction at 130 MeV deuteron energy are compared with the theoretical predictions obtained with a coupled-channel extension of the CD Bonn potential with virtual Delta-isobar excitation, without and with inclusion of the long-range Coulomb force. The Coulomb effect is studied on the basis of th

  55. J. -G. Caputo, E. V. Kazantseva, A. I. Maimistov

    We analyze the interaction of an electromagnetic spike (one cycle) with a thin layer of ferroelectric medium with two equilibrium states. The model is the set of Maxwell equations coupled to the undamped Landau-Khalatnikov equation, where we do not assume slowly varying envelopes. From linear scattering theory, we show that low amplitude pulses can be comple

  56. Alexandre Jollivet

    In this paper, we consider inverse scattering and inverse boundary value problems at sufficiently large and fixed energy for the multidimensional relativistic Newton equation with an external potential $V$, $V\in C^2$. Using known results, we obtain, in particular, theorems of uniqueness.

  57. M. Chuaqui, R. Hernandez

    We investigate the relationship between the univalence of $f$ and of $h$ in the decomposition $f=h+\bar{g}$ of a sense-preserving harmonic mapping defined in the unit disk $\mathbb{D}\subset\mathbb{C}$. Among other results, we determine the holomorphic univalent maps $h$ for which there exists $c>0$ such that every harmonic mapping of the form $f=h+\bar{g}$

  58. Olivier Gues, Guy Métivier, Mark Williams, Kevin Zumbrun

    Extending investigations of Métivier&Zumbrun in the hyperbolic case, we treat stability of viscous shock and boundary layers for viscous perturbations of multidimensional hyperbolic systems with characteristics of variable multiplicity, specifically the construction of symmetrizers in the low-frequency regime where variable multiplicity plays a role. At the

  59. M. Chuaqui, P. Duren, B. Osgood

    A general criterion in terms of the Schwarzian derivative is given for global univalence of the Weierstrass--Enneper lift of a planar harmonic mapping. Results on distortion and boundary regularity are also deduced. Examples are given to show that the criterion is sharp. The analysis depends on a generalized Schwarzian defined for conformal metrics and on a

  60. C. Cortazar, M. Elgueta, J. D. Rossi, N. Wolanski

    We present a model for nonlocal diffusion with Neumann boundary conditions in a bounded smooth domain prescribing the flux through the boundary. We study the limit of this family of nonlocal diffusion operators when a rescaling parameter related to the kernel of the nonlocal operator goes to zero. We prove that the solutions of this family of problems conver

  61. C. Cortazar, M. Elgueta, J. D. Rossi, N. Wolanski

    We study a nonlocal diffusion operator in a bounded smooth domain prescribing the flux through the boundary. This problem may be seen as a generalization of the usual Neumann problem for the heat equation. First, we prove existence, uniqueness and a comparison principle. Next, we study the behavior of solutions for some prescribed boundary data including blo

  62. Łukasz Kruk, John Lehoczky, Steven Shreve

    This paper presents a second-order heavy traffic analysis of a single server queue that processes customers having deadlines using the earliest-deadline-first scheduling policy. For such systems, referred to as real-time queueing systems, performance is measured by the fraction of customers who meet their deadline, rather than more traditional performance me

  63. C. Cortazar, M. Elgueta, J. D. Rossi

    Let $Ω$ be a bounded smooth domain in $\RR^N$. We consider the problem $u_t= Δu + V(x) u^p$ in $Ω\times [0,T)$, with Dirichlet boundary conditions $u=0$ on $\partial Ω\times [0,T)$ and initial datum $u(x,0)= M ϕ(x)$ where $M \geq 0$, $ϕ$ is positive and compatible with the boundary condition. We give estimates for the blow up time of solutions for large valu

  64. Peter Neal, Gareth Roberts

    In this paper we shall consider optimal scaling problems for high-dimensional Metropolis--Hastings algorithms where updates can be chosen to be lower dimensional than the target density itself. We find that the optimal scaling rule for the Metropolis algorithm, which tunes the overall algorithm acceptance rate to be 0.234, holds for the so-called Metropolis-

  65. Armando J. Maccori, Jose A. Verderesi

    The goal of this paper is to establish the classification of all homogeneous surfaces of 3-sphere by using the moving frame method. We will show that such surfaces are 2-spheres and flat torus.

  66. Naoto Morikawa

    This paper proposes a new mathematical framework that can be applied to biological problems such as analysis of the structures of proteins and protein complexes. In particular, it gives a new method for encoding the three-dimensional structure of a protein into a binary sequence, where proteins are approximated by a folded tetrahedron sequence. It also gives

  67. Sacha C. Blumen

    A representation of the Birman-Wenzl-Murakami algebra BW_{t}(-q^{2n},q) exists in the centraliser algebra End_{U_q(osp(1|2n))}(V^{\otimes t}), where V is the fundamental (2n+1)-dimensional irreducible U_{q}(osp(1|2n))-module. This representation is defined using permuted R-matrices acting on V^{\otimes t}. A complete set of projections onto and intertwiners

  68. Friedrich Haslinger, Bernard Helffer

    In this paper we discuss compactness of the canonical solution operator to d-bar on weigthed L^2- spaces on C^n. For this purpose we apply ideas which were used for the Witten Laplacian in the real case and various methods of spectral theory of these operators. We also point out connections to the theory of Dirac and Pauli operators.

  69. Friedrich Haslinger

    In this paper we characterize compactness of the canonical solution operator to d-bar on weigthed $L^2$ spaces on $\mathbb C.$ For this purpose we consider certain Schrödinger operators with magnetic fields and use a condition which is equivalent to the property that these operators have compact resolvents. We also point out what are the obstructions in the

  70. Miklós Csörgő, Barbara Szyszkowicz, Lihong Wang

    In this paper we study strong approximations (invariance principles) of the sequential uniform and general Bahadur--Kiefer processes of long-range dependent sequences. We also investigate the strong and weak asymptotic behavior of the sequential Vervaat process, that is, the integrated sequential Bahadur--Kiefer process, properly normalized, as well as that

  71. Domenico Marinucci, Giovanni Peccati

    Let T* be a random field indexed by an Abelian compact group G, and suppose that T* has the form T* = F(T(g)), where T is Gaussian and isotropic. The aim of this paper is to establish high-frequency central limit theorems for the Fourier coefficients associated to T*. The proofs of our main results involve recently established criteria for the weak convergen

  72. J. Gómez-Torrecillas

    We investigate which aspects of recent developments on Galois corings and comodules admit a formulation in terms of comonads. This approach hopefully will permit of focusing in what is specific in each particular future situation, having some relevant general results for granted. The general theory is applied to the study of comodules over corings over firm

  73. Chiara Zanini, Fabio Zanolin

    We deal with the periodic boundary value problem for a second-order nonlinear ODE which includes the case of the Nagumo type equation $v_{xx} - g v + n(x) F(v) = 0,$ previously considered by Grindrod and Sleeman and by Chen and Bell in the study of the model of a nerve fiber with excitable spines. In a recent work we proved a result of nonexistence of nontri

  74. Hira L. Koul, Shiqing Ling

    This paper addresses the problem of fitting a known distribution to the innovation distribution in a class of stationary and ergodic time series models. The asymptotic null distribution of the usual Kolmogorov--Smirnov test based on the residuals generally depends on the underlying model parameters and the error distribution. To overcome the dependence on th

  75. Valentin Patilea, Jean-Marie Rolin

    A model for competing (resp. complementary) risks survival data where the failure time can be left (resp. right) censored is proposed. Product-limit estimators for the survival functions of the individual risks are derived. We deduce the strong convergence of our estimators on the whole real half-line without any additional assumptions and their asymptotic n

  76. Jea-Man Ahn, Yong Su Shin

    We find a sufficient condition that $\H$ is not level based on a reduction number. In particular, we prove that a graded Artinian algebra of codimension 3 with Hilbert function $\H=(h_0,h_1,..., h_{d-1}>h_d=h_{d+1})$ cannot be level if $h_d\le 2d+3$, and that there exists a level O-sequence of codimension 3 of type $\H$ for $h_d \ge 2d+k$ for $k\ge 4$. Furth

  77. Jean-François Dupuy, Ion Grama, Mounir Mesbah

    The relationship between a time-dependent covariate and survival times is usually evaluated via the Cox model. Time-dependent covariates are generally available as longitudinal data collected regularly during the course of the study. A frequent problem, however, is the occurence of missing covariate data. A recent approach to estimation in the Cox model in t

  78. Bhaskar Bhattacharya

    The iterative proportional fitting procedure (IPFP) was introduced formally by Deming and Stephan in 1940. For bivariate densities, this procedure has been investigated by Kullback and Rüschendorf. It is well known that the IPFP is a sequence of successive I-projections onto sets of probability measures with fixed marginals. However, when finding the I-proje

  79. C. Houdré, P. Marchal

    We estimate a median of $f(X_t)$ where $f$ is a Lipschitz function, $X$ is a Lévy process and $t$ an arbitrary time. This leads to concentration inequalities for $f(X_t)$. In turn, corresponding fluctuation estimates are obtained under assumptions typically satisfied if the process has a regular behavior in small time and a, possibly different, regular behav

  80. Alessio Corti, Vasily Golyshev

    We compute the Hodge numbers of the variation of Hodge structure of the middle cohomology (with compact support) of the Landau-Ginzburg model dual to a weighted projective space. We state a conjectural formula for the Hodge numbers of general hypergeometric variations. We show that a general Landau-Ginzburg fibre is birational to a Calabi-Yau variety if and

  81. Aureli Alabert, Marco Ferrante

    We consider linear stochastic differential-algebraic equations with constant coefficients and additive white noise. Due to the nature of this class of equations, the solution must be defined as a generalised process (in the sense of Dawson and Fernique). We provide sufficient conditions for the law of the variables of the solution process to be absolutely co

  82. Piotr T. Chrusciel, Szymon Leski

    The study of Einstein equations leads naturally to Cauchy problems with initial data on hypersurfaces which closely resemble hyperboloids in Minkowski space-time, and with initial data with polyhomogeneous asymptotics, that is, with asymptotic expansions in terms of powers of ln r and inverse powers of r. Such expansions also arise in the conformal method fo

  83. Cyril Odasso

    We establish a general criterion which ensures exponential mixing of parabolic Stochastic Partial Differential Equations (SPDE) driven by a non additive noise which is white in time and smooth in space. We apply this criterion on two representative examples: 2D Navier-Stokes (NS) equations and Complex Ginzburg-Landau (CGL) equation with a locally Lipschitz n

  84. Tsuyoshi Kobayashi, Yo&#39;av Rieck

    We prove that if $K_1 \subset M_1,...,K_n \subset M_n$ are m-small knots in closed orientable 3-manifolds then the Heegaard genus of $E(#_{i=1}^n K_i)$ is strictly less than the sum of the Heegaard genera of the $E(K_i)$ ($i=1,...,n$) if and only if there exists a proper subset $I$ of $\{1,...,n\}$ so that $#_{i \in I} K_i$ admits a primitive meridian. This

  85. Takashi Taniguchi

    Let $k$ be a number field. In this paper, we give a formula for the mean value of the square of class numbers times regulators for certain families of quadratic extensions of $k$ characterized by finitely many local conditions. We approach this by using the theory of the zeta function associated with the space of pair of quaternion algebras.

  86. Paola Cattabriga

    In 1891 Cantor presented two proofs with the purpose to establish a general theorem that any set can be replaced by a set of greater power. Cantor&#39;s power set theorem can be considered to be an extension of Cantor&#39;s 1891 second proof and its argument makes use of a well-known self-referring statement. In this article it is shown that, defining the re

  87. Jan Kotanski

    The spectrum of Supersymmetric Yang-Mills Quantum Mechanics (SYMQM) in D=4 dimensions for SU(2) gauge group is computed for a maximal number of bosonic quanta $B\le60$ in the two-fermion sector with the angular momentum $j=0$. We analyse the eigenfunctions of discrete and continuous spectra, test the scaling relation for the continuous spectrum and confirm t

  88. T. Banks

    I discuss a formulation of M-theory at null infinity, which is based on general principles of holographic space-time, and is manifestly covariant. The construction utilizes a certain Type II Von Neumann algebra, which provides a kinematic framework, alternative to Fock Space, for describing the scattering states of eleven dimensional asymptotically flat M-th

  89. P. Bouwknegt, J. Evslin, B. Jurco, V. Mathai

    We derive a formula for D3-brane charge on a compact spacetime, which includes torsion corrections to the tadpole cancellation condition. We use this to classify D-branes and RR fluxes in type II string theory on RP^3xRP^{2k+1}xS^{6-2k} with torsion H-flux and to demonstrate the conjectured T-duality to S^3xS^{2k+1}xS^{6-2k} with no flux. When k=1, H\neq 0 a

  90. Alexey Pronin, Tatsu Takeuchi

    We study the lifetimes of TeV-scale heavy neutral leptons (Majorana neutrinos) that appear in a model suggested by Okamura et al. [2]. We develop a convenient way to parametrize the neutrino mass texture of the model, and illustrate our method by calculating the mass spectrum, decay widths, and lifetimes of the heavy particles over the entire parameter space

  91. L. Clavelli

    The observation in the universe of a small but positive vacuum energy strongly suggests, in the string landscape picture, that there will ultimately be a phase transition to an exactly supersymmetric universe. This ground state or &#34;true vacuum&#34; of the universe could be similar to the minimal supersymmetric standard model with all the susy breaking pa

  92. V. Elias, T. G. Steele

    We demonstrate to two-loop order that an intermediate symmetrically embedded Pati-Salam $SU(2)_L \times SU(2)_R \times SU(4)$ level of symmetry is all that is necessary to accommodate empirical values of $α(M_z), α_s(M_z)$ and $\sin^2θ_w(M_z)$ within a grand unification context but with a high (10^{14} GeV) intermediate mass scale and with a concomitant high

  93. Oleg Andreev, Valentine I. Zakharov

    We present results of modeling the temperature dependence of the spatial string tension and thermal phase transition in a five-dimensional framework nowadays known as AdS/QCD. For temperatures close to the critical one we find a behaviour remarkably consistent with the lattice results.

  94. Vittorio Del Duca

    QCD is an extensively developed and tested gauge theory, which models the strong interactions in the high-energy regime. In this talk, I shall review the considerable progress which has been achieved in the last few years in the most actively studied QCD topics: Monte Carlo models, higher-order corrections, and parton distribution functions. Thanks to that,

  95. D. Gomez Dumm, A. G. Grunfeld, N. N. Scoccola

    We present a comparative analysis of chiral quark models which include nonlocal covariant four-fermion couplings. We consider two alternative ways of introducing the nonlocality, as well as various shapes for the momentum-dependent form factors governing the effective interactions. In all cases we study the behavior of model parameters and analyze numerical

  96. Matteo Cacciari, Paolo Nason, Carlo Oleari

    This talk summarizes the results of a phenomenological analysis of heavy quark fragmentation data published by the CLEO and BELLE collaborations at \sqrt{s} = 10.6 GeV and by the LEP collaborations at \sqrt{s} = 91.2 GeV. Several theoretical ingredients are employed: next-to-leading order initial conditions, evolution and coefficient functions; soft-gluon re

  97. G. Cynolter, E. Lendvai

    Recently a new dynamical symmetry breaking model of electroweak interactions was proposed based on interacting fermions. Two fermions of different SU(2) representations form a symmetry breaking condensate and generate the lepton and quark masses. The weak gauge bosons get their usual standard model masses from a gauge invariant Lagrangian of a composite doub

  98. M. Grazzini

    Non resonant production of WW pairs is the most important background in the Higgs search in the range 155 \ltap M_H \ltap 170 GeV at the LHC. We consider QCD corrections to WW pair production in hadron collisions and present a calculation which consistently combines NLO corrections with soft-gluon resummation at small transverse momenta of the WW pair. Spin

  99. B. Ananthanarayan

    At the International Linear Collider large beam polarization of both the electron and positron beams will enhance the signature of physics due to interactions that are beyond the Standard Model. Here we review our recently obtained results on a general model independent method of determining for an arbitary one-particle inclusive state the space-time structu

  100. Panying Chen, Ahmad Idilbi, Xiangdong Ji

    We study deep-inelastic scattering factorization on a nucleon in the end-point regime $x_B \sim 1-{\cal O}(Λ_{\rm QCD}/Q)$ where the traditional operator product expansion is supposed to fail. We argue, nevertheless, that the standard result holds to leading order in $1-x_B$ due to the absence of the scale dependence on $(1-x_B)Q$. Refactorization of the sca