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June 2007 arXiv papers — page 21

Showing 2,001–2,100 of 4,521 papers

  1. F. Fehrer, P. M. Dinh, M. Baer, P. -G. Reinhard

    We investigate the dynamical evolution of a Na$_8$ cluster embedded in Ar matrices of various sizes from N=30 to 1048. The system is excited by an intense short laser pulse leading to high ionization stages. We analyze the subsequent highly non-linear motion of cluster and Ar environment in terms of trajectories, shapes, and energy flow. The most prominent e

  2. R. Campoamor-Stursberg

    We analyze under which conditions the missing label problem associated to a reduction chain $\frak{s}^{\prime}\subset \frak{s}$ of (simple) Lie algebras can be completely solved by means of an Inönü-Wigner contraction $\frak{g}$ naturally related to the embedding. This provides a new interpretation of the missing label operators in terms of the Casimir opera

  3. Begoña Alarcón, Carlos Gutierrez, José Martínez-Alfaro

    Let a>0, F: R^2 -> R^2 be a differentiable (not necessarily C^1) map and Spec(F) be the set of (complex) eigenvalues of the derivative F'(p) when p varies in R^2. (a) If Spec(F) is disjoint of the interval [1,1+a[, then Fix(F) has at most one element, where Fix(F) denotes the set of fixed points of F. (b) If Spec(F) is disjoint of the real line R, then F

  4. Jouni Parkkonen, Frédéric Paulin

    Given a family of (almost) disjoint strictly convex subsets of a complete negatively curved Riemannian manifold M, such as balls, horoballs, tubular neighborhoods of totally geodesic submanifolds, etc, the aim of this paper is to construct geodesic rays or lines in M which have exactly once an exactly prescribed (big enough) penetration in one of them, and o

  5. Yu. Andreev, N. Krasnikov, A. Toropin

    We study the $e^{\pm}μ^{\mp} + E^{miss}_T$ and $l^+l^- + E^{miss}_T$ signatures $(l = e, μ)$ for different values of $\tanβ$ in the mSUGRA model. With $\tanβ$ rising, we observe a characteristic change in the shape of dilepton mass spectra in $l^+l^- + E^{miss}_T $ versus $e^{\pm}μ^{\mp}$ final states reflecting the decrease of $\tildeχ^0_2 \to l^+l^- \tilde

  6. R. S. Kemble

    In this paper the absolute value or distance from the origin analogue of the classical Khintchine-Groshev theorem is established for a single linear form with a `slowly decreasing' error function.

  7. Dawei Xu, Stefanie Komossa, Hongyan Zhou, Tinggui Wang

    The properties of narrow-line Seyfert 1 (NLS1) galaxies, the links and correlations between them, and the physics behind them, are still not well understood. Apart from accretion rates and black hole masses, density and outflows were speculated to be among the main drivers of the NLS1 phenomenon. Here, we utilize the diagnostic power of the [SII]6716,6731 in

  8. R. P. Mignani, R. Perna, N. Rea, G. L. Israel

    Recent radio observations have unveiled the existence of a number of radio pulsars with spin-down derived magnetic fields in the magnetar range. However, their observational properties appears to be more similar to classical radio pulsars than to magnetars. To shed light on this puzzle we first have to determine whether the spin-down derived magnetic field v

  9. Remo Ruffini, Maria Grazia Bernardini, Carlo Luciano Bianco, Letizia Caito

    We outline the main results of our GRB model, based on the three interpretation paradigms we proposed in July 2001, comparing and contrasting them with the ones in the current literature. Thanks to the observations by Swift and by VLT, this analysis points to a "canonical GRB" originating from markedly different astrophysical scenarios. The communali

  10. J. Camacho, S. Torres, J. Isern, L. G. Althaus

    The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly to the mass budget of our Galaxy. However, several constraints on the role played by regular carbon-oxygen white dwarfs exist. Massivewhite dwarfs are

  11. Raluca Mocanu, Marian Ioan Munteanu

    The aim of this research is the study of Gray curvature identities, introduced by Alfred Gray in \cite{kn:Gra76} for the class of almost hermitian manifolds. As known till now, there is no equivalent for the class of almost contact manifolds. For this purpose we use the Boohby-Wang fibration and the warped manifolds construction in order to establish which i

  12. K. R. Priolkar, R. Rawat

    Magnetic and transport properties of Ti substituted La$_{0.67}$Sr$_{0.33}$MnO$_3$ are drastically affected with a change in preparation conditions. Low temperature infra-red absorption measurements reveal that this is perhaps due to inhomogeniety in substitution of Ti$^{4+}$ on Mn sites. It is found that, in the high temperature annealed samples, the substit

  13. M. T. Beltran, R. Cesaroni, L. Moscadelli, C. Codella

    Context. G24.78+0.08 A1 is a 20 Msun star surrounded by a hypercompact (HC) HII region, driving a CO bipolar outflow, and located at the center of a massive rotating toroid undergoing infall towards the HC region. Recent water maser observations suggest that the HC region is expanding and accretion onto the star is halted. Aims. This study aims to confirm th

  14. M. Dominik, N. J. Rattenbury, A. Allan, S. Mao

    (abridged) The discovery of OGLE 2005-BLG-390Lb, the first cool rocky/icy exoplanet, impressively demonstrated the sensitivity of the microlensing technique to extra-solar planets below 10 M_earth. A planet of 1 M_earth in the same spot would have provided a detectable deviation with an amplitude of ~ 3 % and a duration of ~ 12 h. An early detection of a dev

  15. The DELPHI Collaboration, J. Abdallah

    Measurements of Zgamma* production are presented using data collected by the DELPHI detector at centre-of-mass energies ranging from 183 to 209 GeV, corresponding to an integrated luminosity of about 667 pb^{-1}. The measurements cover a wide range of the possible final state four-fermion configurations: hadronic and leptonic (e+ e- q qbar, mu+ mu- q qbar, q

  16. Sebastian Jester, Klaus Meisenheimer, Andre' Martel, Eric Perlman

    We present far-ultraviolet (UV) observations at 150 nm of the jet of the quasar 3C 273 obtained with the Advanced Camera for Survey's Solar Blind Channel (ACS/SBC) on board the Hubble Space Telescope. While the jet morphology is very similar to that in the optical and near-ultraviolet, the spectral energy distributions (SEDs) of the jet's sub-regions

  17. T. P. Roberts

    Ultraluminous X-ray sources (ULXs) are amongst the most intriguing of X-ray source classes. Their extreme luminosities - greater than 10^39 erg/s in the 0.3 - 10 keV band alone - suggest either the presence of black holes larger than those regularly encountered in our own Galaxy (the Galactic centre excepted), or sources apparently radiating well above the E

  18. The DELPHI Collaboration, J. Abdallah

    The DELPHI detector at LEP has been used to measure multi-muon bundles originating from cosmic ray interactions with air. The cosmic events were recorded in ``parasitic mode'' between individual e+e- interactions and the total live time of this data taking is equivalent to 1.6x10^6 seconds. The DELPHI apparatus is located about 100 metres underground

  19. B. Ananthanarayan, P. N. Pandita

    We carry out a detailed analysis of sparticle mass spectrum in supersymmetric grand unified theories. We consider the spectroscopy of the squarks and sleptons in SU(5) and SO(10) grand unified theories, and show how the underlying supersymmetry breaking parameters of these theories can be determined from a measurement of different sparticle masses. This anal

  20. S. Ramstedt, F. L. Schoeier, H. Olofsson

    The S-stars have been suggested to be a brief transitional phase as stars evolve from oxygen-rich M-type stars into carbon stars, through the dredge up of carbon from He-shell burning. As possible transition objects, S-stars might help achieve a deeper understanding of the chemical evolution as a star ascends the AGB, as well as shed more light on the mass-l

  21. Y. Ascasibar, J. M. Diego

    We present a simple model to describe the dark matter density, the gas density, and the gas temperature profiles of galaxy clusters. Analytical expressions for these quantities are given in terms of only five free parameters with a clear physical meaning: the mass M of the dark matter halo (or the characteristic temperature T_0), the characteristic scale rad

  22. S. Miglioranzi

    Studies of charm and beauty production in ep collisions with a center-of-mass energy of 318 GeV are reported from the two HERA collaborations, H1 and ZEUS. The analyses make use of both the HERA-I data sample recorded between 1996 and 2000 and a sample from HERA-II, which started in 2003. The cross sections measured by both H1 and ZEUS experiments are compar

  23. C. Barrabes, P. A. Hogan

    We describe a natural inhomogeneous generalization of high frequency plane gravitational waves. The waves are high frequency waves of the Kundt type whose null propagation direction in space-time has vanishing expansion, twist and shear but is not covariantly constant. The introduction of a cosmological constant is discussed in some detail and a comparison i

  24. S. Verley, S. Leon, L. Verdes-Montenegro, F. Combes

    The AMIGA project aims to build a well defined and statistically significant reference sample of isolated galaxies in order to estimate the environmental effects on the formation and evolution of galaxies. The goal of this paper is to provide a measure of the environment of the isolated galaxies in the AMIGA sample, quantifying the influence of the candidate

  25. Sylvie Paycha

    We discuss possible extensions of the classical Chern-Weil formalism to an infinite dimensional setup. This is based on joint work with Steven Rosenberg, joint work with Simon Scott and joint work with Jouko Mickelsson.

  26. Sylvie Paycha

    We show that the noncommutative residue density, resp. the cut-off regularised integral are the only closed linear, resp. continuous closed linear forms on certain classes of symbols. This leads to alternative proofs of the uniqueness of the noncommutative residue, resp. the canonical trace as linear, resp. continuous linear forms on certain classes of class

  27. Massimo Pica Ciamarra, Gennaro Miele, Leopoldo Milano, Mario Nicodemi

    The important task of determining the connectivity of gene networks, and at a more detailed level even the kind of interaction existing between genes, can nowadays be tackled by microarraylike technologies. Yet, there is still a large amount of unknowns with respect to the amount of data provided by a single microarray experiment, and therefore reliable gene

  28. D. H. F. M. Schnitzeler, P. Katgert, A. G. de Bruyn

    We investigate the distribution and properties of Faraday rotating and synchrotron emitting regions in the Galactic ISM in the direction of the Galactic anti-centre. We apply Faraday tomography to a radio polarization dataset that we obtained with the WSRT. We developed a new method to calculate a linear fit to periodic data, which we use to determine rotati

  29. A. Malizia, R. Landi, L. Bassani, A. J. Bird

    For a significant number of the sources detected at high energies (>10 keV) by the INTEGRAL/IBIS and Swift/BAT instruments there is either a lack information about them in the 2-10 keV range or they are totally unidentified. Herein, we report on a sample of 34 IBIS AGN or AGN candidate objects for which there is X-ray data in the Swift/XRT archive. Thanks to

  30. Giuseppe Mussardo

    We analyze non-integrable deformations of two-dimensional N=1 supersymmetric quantum field theories with kink excitations. As example, we consider the multi-frequency Super Sine Gordon model. At weak coupling, this model is robust with respect to kink confinement phenomena, in contrast to the purely bosonic case. If we vary the coupling, the model presents a

  31. Yuji Koike, Kazuhiro Tanaka

    We prove factorization and gauge invariance of the twist-3 single-spin-dependent cross section in the leading order perturbative QCD, which was missing in the previous literature. We emphasize that the consistency relation from the Ward identities for color gauge invariance is crucial to guarantee the cancelation among the various gauge-noninvariant contribu

  32. Pierre-Louis Curien, Hugo Herbelin

    The notion of abstract Boehm tree has arisen as an operationally-oriented distillation of works on game semantics, and has been investigated in two papers. This paper revisits the notion, providing more syntactic support and more examples (like call-by-value evaluation) illustrating the generality of the underlying computing device. Precise correspondences b

  33. Jun-Young Lee, Ki-Suk Lee, Sangkook Choi, Konstantin Y. Guslienko

    The magnetic field (or electric current) driven domain-wall motion in magnetic nanostripes is of considerable interest because it is essential to the performance of information storage and logic devices. One of the currently key problems is to unveil the complex behaviors of oscillatory domain-wall motions under applied magnetic fields stronger than the so-c

  34. A. Dumitru, E. Iancu, L. Portugal, G. Soyez

    Within the framework of a (1+1)-dimensional model which mimics evolution and scattering in QCD at high energy, we study the influence of the running of the coupling on the high-energy dynamics with Pomeron loops. We find that the particle number fluctuations are strongly suppressed by the running of the coupling, by at least one order of magnitude as compare

  35. ZEUS Collaboration, S. Chekanov

    Bose-Einstein correlations of charged and neutral kaons have been measured in e+-p deep inelastic scattering with an integrated luminosity of 121 pb-1 using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, Q_12=sqrt{-(p_1-p_2)^2}, assuming a Gaussian shape for the pa

  36. R. Vlokh, I. Vlokh, O. Moroz, Yu. Nastishin

    It has been shown that conformational modifications of Hb induced by ethanol consumption can be visualized in optical spectra studying oxygenation kinetics of hemoglobin or mixing hemoglobin with Cibacron blue dye. Better dye affinity of blood proteins extracted from alcoholised rats with respect to those from non-alcoholised ones confirms that ethanol and i

  37. Yoshio Koide

    The recent devolopment on the charged lepton mass forumula m_e+m_μ+m_τ={2/3}(\sqrt{m_e}+\sqrt{m_μ}+\sqrt{m_τ})^2 is reviewed. An S_3 or A_4 model will be promising for the mass relation.

  38. Probir Roy

    Proposed symmetry relations, e.g., quark-lepton complementarity (QLC) or tribimaximal mixing (TBM), need to be imposed at a high scale $\wedge \sim 10^{12}$ GeV characterising the large masses of right-handed neutrinos required to implement the seesaw mechanism. RG evolution down to the laboratory scale $λ\sim 10^3$ GeV, generically prone to spoil these rela

  39. Yuji Kajiyama

    In this talk, we investigate the implications of R-parity violating (RPV) operators in a model with family symmetry. Family symmetry can determine the form of RPV operators as well as the Yukawa matrices. We consider a concrete model with non-abelian discrete symmetry Q_6, which has only three RPV trilinear operators with no baryon number violating terms. We

  40. N. E. Csima

    In this paper we study F-crystals with self-dual structure over base schemes of characteristic p. We generalize Katz's Newton-Hodge Filtration Theorem to F-crystals with self-dual structure.

  41. Yi Xie, Chang-Yin Huang, Wei-Hua Lei

    Many models of gamma-ray bursts suggest a common central engine: a black hole of several solar masses accreting matter from a disk at an accretion rate from 0.01 to 10 M_\sun / s. The inner region of the disk is cooled by neutrino emission and large amounts of its binding energy were liberated, which could trigger the fireball. We improve the neutrino-domina

  42. K. Hagino, Y. Watanabe

    We invert experimental data for heavy-ion fusion reactions at energies well below the Coulomb barrier in order to directly determine the internucleus potential between the colliding nuclei. In contrast to the previous applications of the inversion formula, we explicitly take into account the effect of channel couplings on fusion reactions, by assuming that f

  43. Youngman Kim, Bum-Hoon Lee, Siyoung Nam, Chanyong Park

    In the framework of a holographic QCD approach we study an influence of matters on the deconfinement temperature, $T_c$. We first consider quark flavor number ($N_f$) dependence of $T_c$. We observe that $T_c$ decreases with $N_f$, which is consistent with a lattice QCD result. We also delve into how the quark number density $ρ_q$ affects the value of $T_c$.

  44. N. Magnani, A. Hiess, R. Caciuffo, E. Colineau

    We report the results of inelastic neutron scattering experiments on NpCoGa$_{5}$, an isostructural analogue of the PuCoGa$_{5}$ superconductor. Two energy scales characterize the magnetic response in the antiferromagnetic phase. One is related to a non-dispersive excitation between two crystal field levels. The other at lower energies corresponds to dispers

  45. H. F. Arellano, W. G. Love

    A microscopic description of the quasielastic (p,n) charge-exchange reaction (here, charge-exchange scattering between analogue states) is presented and discussed. Emphasis is focused on the spin-isospin structure of the projectile-target coupling. The model is a coupled-channel extension of the full-folding optical model approach (OMP) developed for nucleon

  46. H. M. Wiseman

    Bohmian mechanics (BM) is a popular interpretation of quantum mechanics in which particles have real positions. The velocity of a point x in configuration space is defined as the standard probability current j(x) divided by the probability density P(x). However, this ``standard'' j is in fact only one of infinitely many that transform correctly and s

  47. Aiguo Xu, X. F. Pan, Guangcai Zhang, Jianshi Zhu

    The collapse of cavities under shock is a key problem in various fields ranging from erosion of material, ignition of explosive, to sonoluminescence, etc. We study such processes using the material-point-method developed recently in the field of solid physics. The main points of the research include the relations between symmetry of collapsing and the streng

  48. Viktoria Rojkova, Mehmed Kantardzic

    The traffic behavior of University of Louisville network with the interconnected backbone routers and the number of Virtual Local Area Network (VLAN) subnets is investigated using the Random Matrix Theory (RMT) approach. We employ the system of equal interval time series of traffic counts at all router to router and router to subnet connections as a represen

  49. Raanan Schul

    This note is intended to be a supplement to the bi-Lipschitz decomposition of Lipschitz maps shown in [Sch]. We show that in the case of 1-Ahlfors-regular sets, the condition of having `Big Pieces of bi-Lipschitz Images' (BPBI) is equivalent to a Carleson condition.

  50. Bhalchandra D. Thatte, Mike Steel

    A pedigree is a directed graph that describes how individuals are related through ancestry in a sexually-reproducing population. In this paper we explore the question of whether one can reconstruct a pedigree by just observing sequence data for present day individuals. This is motivated by the increasing availability of genomic sequences, but in this paper w

  51. H. E. Lomelí, J. D. Meiss, R. Ramírez-Ros

    We study perturbations of diffeomorphisms that have a saddle connection between a pair of normally hyperbolic invariant manifolds. We develop a first-order deformation calculus for invariant manifolds and show that a generalized Melnikov function or Melnikov displacement can be written in a canonical way. This function is defined to be a section of the norma

  52. Katrin Becker, Yu-Chieh Chung, Guangyu Guo

    We derive stability conditions for the critical points of the no-scale scalar potential governing the dynamics of the complex structure moduli and the axio-dilaton in compactifications of type IIB string theory on Calabi-Yau three-folds. We discuss a concrete example of a T^6 orientifold. We then consider the four-dimensional theory obtained from compactific

  53. Omer Friedland, Sasha Sodin

    Let || . || be a norm on R^n. Averaging || (\eps_1 x_1, ..., \eps_n x_n) || over all the 2^n choices of \eps = (\eps_1, ..., \eps_n) in {-1, +1}^n, we obtain an expression ||| . ||| which is an unconditional norm on R^n. Bourgain, Lindenstrauss and Milman showed that, for a certain (large) constant η> 1, one may average over (ηn) (random) choices of \eps and

  54. F. Delduc, E. Ivanov

    Using an N=4, d=1 superfield approach, we construct an N=8 supersymmetric action of the self-interacting off-shell N=8 multiplet {\bf (1, 8, 7)}. This action is found to be invariant under the exceptional N=8, d=1 superconformal group F(4) with the R-symmetry subgroup SO(7). The general N=8 supersymmetric {\bf (1, 8, 7)} action is a sum of the superconformal

  55. J. Magnen, V. Rivasseau

    We propose to treat the $ϕ^4$ Euclidean theory constructively in a simpler way. Our method, based on a new kind of "loop vertex expansion", no longer requires the painful intermediate tool of cluster and Mayer expansions.

  56. H1 Collaboration

    The average charged track multiplicity and the normalised distribution of the scaled momentum, $\xp$, of charged final state hadrons are measured in deep-inelastic $\ep$ scattering at high $Q^2$ in the Breit frame of reference. The analysis covers the range of photon virtuality $100 < Q^2 < 20 000 \GeV^{2}$. Compared with previous results presented by HERA e

  57. R. L. C. Vink

    The isotropic-to-nematic transition in liquid crystals is studied in d=3 spatial dimensions. A simulation method is proposed to measure the angle dependent interfacial tension g(theta), with theta the anchoring angle of the nematic phase at the interface. In addition, an alternative liquid crystal model is introduced, defined on a lattice. The advantage of t

  58. Egor Babaev, N. W. Ashcroft

    Non-classical response to rotation is a hallmark of quantum ordered states such as superconductors and superfluids. The rotational responses of all currently known single-component &#34;super&#34; states of matter (superconductors, superfluids and supersolids) are largely described by two fundamental principles and fall into two categories according to wheth

  59. Fedor Nazarov, Mikhail Sodin

    Let N(f) be a number of nodal domains of a random Gaussian spherical harmonic f of degree n. We prove that as n grows to infinity, the mean of N(f)/n^2 tends to a positive constant, and that N(f)/n^2 exponentially concentrates around that constant. This result is consistent with predictions made by Bogomolny and Schmit using a percolation-like model for noda

  60. Julien Malzac

    I review current models used to interpret the spectra and variability of microquasars. Among other things, I discuss the structure of the accretion flow and its dependence on mass accretion rate, the intrinsic connection between hot comptonizing corona and compact radio jet in the hard state, as well as possible models for the spectral hysteresis observed du

  61. Sergei Gukov

    Topological gauge theories in four dimensions which admit surface operators provide a natural framework for realizing homological knot invariants. Every such theory leads to an action of the braid group on branes on the corresponding moduli space. This action plays a key role in the construction of homological knot invariants. We illustrate the general const

  62. J. H. Bauer

    The relationship between the length gauge (LG) and the velocity gauge (VG) exact forms of the photoionization probability amplitude is considered. Our motivation for this paper comes from applications of the Keldysh-Faisal-Reiss (KFR) theory, which describes atoms (or ions) in a strong laser field (in the nonrelativistic approach, in the dipole approximation

  63. Mathias Schulze

    For quasihomogeneous isolated hypersurface singularities, the logarithmic comparison theorem has been characterized explicitly by Holland and Mond. In the non quasihomogeneous case, we give a necessary condition for the logarithmic comparison theorem in terms of the Gauss-Manin system of the singularity. It shows in particular that the logarithmic comparison

  64. Abouzeid. M. Shalaby

    We generalized a class of non-Hermitian Hamiltonians which introduced previously by us in such a way in which every member in the class is non-\textit{PT}-symmetric. For every member of the class, the ground state is a constant with zero energy eigen value. Instead of using an infinite set of coupled operator equations to calculate the metric operator we use

  65. S. I. Denisov, M. Kostur, E. S. Denisova, P. Hänggi

    We study the arrival time distribution of overdamped particles driven by a constant force in a piecewise linear random potential which generates the dichotomous random force. Our approach is based on the path integral representation of the probability density of the arrival time. We explicitly calculate the path integral for a special case of dichotomous dis

  66. Matthieu Mambrini

    We demonstrate that any SU(2) singlet wavefunction can be characterized by a set of Valence Bond occupation numbers, testing dimer presence/vacancy on pairs of sites. This genuine quantum property of singlet states (i) shows that SU(2) singlets share some of the intuitive features of hardcore quantum dimers, (ii) gives rigorous basis for interesting albeit a

  67. H. Mäkelä, K. -A. Suominen

    We present a simple but efficient geometrical method for determining the inert states of spin-S systems. It can be used if the system is described by a spin vector of a spin-S particle and its energy is invariant in spin rotations and phase changes. Our method is applicable to an arbitrary S and it is based on the representation of a pure spin state of a spi

  68. Alexander Postnikov, David Speyer, Lauren Williams

    In this paper we use toric geometry to investigate the topology of the totally non-negative part of the Grassmannian (Gr_{kn})_{\geq 0}. This is a cell complex whose cells Delta_G can be parameterized in terms of the combinatorics of plane-bipartite graphs G. To each cell Delta_G we associate a certain polytope P(G). The polytopes P(G) are analogous to the w

  69. A. A. Isayev

    The unusual temperature behavior of the entropy of the antiferromagnetic (AFM) spin state in symmetric nuclear matter with the Gogny D1S interaction, being larger at low temperatures than the entropy of nonpolarized matter, is related to the dependence of the entropy on the effective masses of nucleons in a spin polarized state. The corresponding conditions

  70. P. S. Howe, U. Lindstrom, L. Wulff

    A kappa-symmetric action for coincident D-branes is presented. It is valid in the approximation that the additional fermionic variables, used to incorporate the non-abelian degrees of freedom, are treated classically. The action is written as a Bernstein-Leites integral on the supermanifold obtained from the bosonic worldvolume by adjoining the extra fermion

  71. Michael Farber, Mark Grant

    The complexity of algorithms solving the motion planning problem is measured by a homotopy invariant TC(X) of the configuration space X of the system. Previously known lower bounds for TC(X) use the structure of the cohomology algebra of X. In this paper we show how cohomology operations can be used to sharpen these lower bounds for TC(X). As an application

  72. Charis Anastopoulos

    We study the decay of unstable states by formulating quantum tunneling as a time-of-arrival problem: we determine the detection probability for particles at a detector located a distance L from the tunneling region. For this purpose, we use a Positive-Operator-Valued-Measure (POVM) for the time-of-arrival determined in quant-ph/0509020 [JMP 7, 122106 (2006)]

  73. Denjoe O&#39;Connor, Christian Saemann

    We develop an analytical approach to scalar field theory on the fuzzy sphere based on considering a perturbative expansion of the kinetic term. This expansion allows us to integrate out the angular degrees of freedom in the hermitian matrices encoding the scalar field. The remaining model depends only on the eigenvalues of the matrices and corresponds to a m

  74. Charis Anastopoulos, Ntina Savvidou

    We formulate quantum tunneling as a time-of-arrival problem: we determine the detection probability for particles passing through a barrier at a detector located a distance L from the tunneling region. For this purpose, we use a Positive-Operator-Valued-Measure (POVM) for the time-of-arrival determined in quant-ph/0509020 [JMP 47, 122106 (2006)]. This only d

  75. Claude Cibils, Maria Julia Redondo, Andrea Solotar

    We provide an intrinsic definition of the fundamental group of a linear category over a ring as the automorphism group of the fibre functor on Galois coverings. If the universal covering exists, we prove that this group is isomorphic to the Galois group of the universal covering. The grading deduced from a Galois covering enables us to describe the canonical

  76. M. I. Katsnelson, A. K. Geim

    We discuss various scattering mechanisms for Dirac fermions in single-layer graphene. It is shown that scattering on a short-range potential (due to, for example, neutral impurities) is mostly irrelevant for electronic quality of graphene, which is likely to be controlled by charged impurities and ripples (microscopic corrugations of a graphene sheet). The l

  77. X. Aslanoglou, A. Cyz, N. Davis, D. d&#39;Enterria

    We present results on the performance of the first prototype of the CASTOR quartz-tungsten sampling calorimeter, to be installed in the very forward region of the CMS experiment at the LHC. This study includes GEANT Monte Carlo simulations of the Cherenkov light transmission efficiency of different types of air-core light guides, as well as analysis of the c

  78. Tomaz Prosen, Iztok Pizorn

    The efficiency of time dependent density matrix renormalization group methods is intrinsically connected with the rate of entanglement growth. We introduce a new measure of entanglement in the space of operators and show, for transverse Ising spin 1/2 chain, that the simulation of observables, contrary to simulation of typical pure quantum states, is efficie

  79. V. A. Kuz&#39;menko

    Inequality of forward and reversed processes in quantum physics means an existence of a memory of quantum system about the initial state. Importance of its experimental study for correct interpretation of quantum mechanics and understanding of a physical base of a consciousness is discussed.

  80. K. Yu. Bliokh, Yu. P. Bliokh, S. Savel&#39;ev, F. Nori

    We consider semiclassical higher-order wave packet solutions of the Schrodinger equation with phase vortices. The vortex line is aligned with the propagation direction, and the wave packet carries a well-defined orbital angular momentum (OAM) $\hbar l$ ($l$ is the vortex strength) along its main linear momentum. The probability current coils around momentum

  81. Pierpaolo Vivo, Satya N. Majumdar

    We introduce and solve exactly a family of invariant 2x2 random matrices, depending on one parameter η, and we show that rotational invariance and real Dyson index βare not incompatible properties. The probability density for the entries contains a weight function and a multiple trace-trace interaction term, which corresponds to the representation of the Van

  82. E. Kuraev, E. Tomasi-Gustafsson, S. Bakmaev, V. Bytev

    The up-down asymmetry in transversally polarized electron proton scattering is induced by the interference between one and two photon exchange amplitudes. Inelastic intermediate hadronic states (different from one-proton state) of the two photon exchange amplitude give rise to contributions containing the square of &#34;large logarithm&#34; (logarithm of the

  83. J. Bol, S. Mueller, E. Berderman, W. de Boer

    Diamonds offer radiation hard sensors, which can be used directly in primary beams. Here we report on the use of a polycrystalline CVD diamond strip sensor as beam monitor of heavy ion beams with up to 2.10^9 lead ions per bunch. The strips allow for a determination of the transverse beam profile to a fraction of the pitch of the strips, while the timing inf

  84. Vyacheslav Boyko, Jiri Patera, Roman O. Popovych

    The invariants of solvable Lie algebras with nilradicals isomorphic to the algebra of strongly upper triangular matrices and diagonal nilindependent elements are studied exhaustively. Bases of the invariant sets of all such algebras are constructed by an original purely algebraic algorithm based on Cartan&#39;s method of moving frames.

  85. S. P. Tsarev, T. Wolf

    We classify all integrable 3-dimensional scalar discrete quasilinear equations Q=0 on an elementary cubic cell of the 3-dimensional lattice. An equation Q=0 is called integrable if it may be consistently imposed on all 3-dimensional elementary faces of the 4-dimensional lattice. Under the natural requirement of invariance of the equation under the action of

  86. Filippo Palombi

    We carry out the renormalization and the Symanzik O(a)-improvement programme for the static vector current in quenched lattice QCD. The scale independent ratio of the renormalization constants of the static vector and axial currents is obtained non-perturbatively from an axial Ward identity with Wilson-type light quarks and various lattice discretizations of

  87. Sujit K. Choudhary, Samir Kunkri, Ramij Rahaman, Anirban Roy

    We discuss the exact cloning of orthogonal but entangled qubits under local operations and classical communication. The amount of entanglement necessary in blank copy is obtained for various cases. Surprisingly this amount is more than 1 ebit for certain set of two nonmaximal but equally entangled states of two qubits system. To clone any three two qubits Be

  88. Miranda C. N. Cheng, Erik Verlinde

    The dyonic 1/4-BPS states in 4D string theory with N=4 spacetime supersymmetry are counted by a Siegel modular form. The pole structure of the modular form leads to a contour dependence in the counting formula obscuring its duality invariance. We exhibit the relation between this ambiguity and the (dis-)appearance of bound states of 1/2-BPS configurations. U

  89. David Blottière

    This article deals with the Eisenstein classes of Hilbert-Blumenthal families of abelian varieties. We first give a coordinate expression of these one at the topological level, using currents defined by Levin. Then we study the degeneration of these Eisenstein classes at a cusp of the Baily-Borel compactification of the Hilbert-Blumenthal variety. We show, u

  90. David M. Bradley

    The divergence of the harmonic series is proved by direct comparison with a series whose nth partial sum telescopes to the natural logarithm of n. The key idea is to apply the classical inequality x>=log(1+x) (valid for x>-1) with x=1/k and sum over k, 1<=k<=n-1.

  91. I. Sakalli, M. Halilsoy

    We consider geodesics motion in a particular Kundt type III spacetime in which Einstein-Yang-Mills equations admit solutions. On a particular surface as constraint we project the geodesics into the (x,y) plane and treat the problem as a 2-dimensional one. Our numerical study shows that chaotic behavior emerges under reasonable conditions.

  92. Donu Arapura

    Given a complex algebraic variety X, we define a natural number called the motivic dimension which measures the amount of transcendental (co)homology of X. It is zero precisely when all the (co)homolgy is spanned by algebraic cycles. Most of this paper is concerned with giving estimates on this number, along with examples where it is small. As an application

  93. B. E. Zhilyaev

    If primordial low-mass black holes (PBH) exist in the Universe than many of stars and planetary bodies appear to be infected by them. This is also true in regard to the Sun and likely Jupiter and Saturn. The availability of even the very low-mass inner relativistic reactor may lead to essential changes in evolution scenario of a celestial body on its lifetim

  94. Alexandru Dimca, Stefan Papadima, Alexander I. Suciu

    We explore the codimension one strata in the degree-one cohomology jumping loci of a finitely generated group, through the prism of the multivariable Alexander polynomial. As an application, we give new criteria that must be satisfied by fundamental groups of smooth, quasi-projective complex varieties. These criteria establish precisely which fundamental gro

  95. A. H. G. Vlooswijk, G. Catalan, A. Janssens, B. Barcones

    Ferroelectrics display spontaneous and switchable electrical polarization. Until recently, ferroelectricity was believed to disappear at the nanoscale; now, nano-ferroelectrics are being considered in numerous applications. This renewed interest was partly fuelled by the observation of ferroelectric domains in films of a few unit cells thickness, promising f

  96. R Assumpcao

    This contribution analyses the classical laws of motion by means of an approach relating time and entropy. We argue that adopting the notion of change of states as opposed to the usual derivation of Newton&#39;s laws in terms of fields a broader picture is obtained, suggesting that diverse branches of physics- classical, quantum, relativistic and statistical

  97. Bau-Sen Du

    By counting the numbers of periodic points of all periods for some interval maps, we obtain infinitely many new congruence identities in number theory.

  98. O. E. Raichev

    The spin-Hall conductivity in spatially-homogeneous two-dimensional electron systems described by the spin-orbit Hamiltonian \hbar Ω_p σis presented as a sum of the universal part Me/8 π\hbar determined by the Berry phase Φ=M π(M is an odd integer, the winding number of the vector Ω_p) and a non-universal part which vanishes under certain conditions determin

  99. Piotr Garbaczewski

    Information functionals allow to quantify the degree of randomness of a given probability distribution, either absolutely (through min/max entropy principles) or relative to a prescribed reference one. Our primary aim is to analyze the &#34;minimum information&#34; assumption, which is a classic concept (R. Balian, 1968) in the random matrix theory. We put s

  100. Damien Regnault, Nicolas Schabanel, Éric Thierry

    Cellular automata are often used to model systems in physics, social sciences, biology that are inherently asynchronous. Over the past 20 years, studies have demonstrated that the behavior of cellular automata drastically changed under asynchronous updates. Still, the few mathematical analyses of asynchronism focus on one-dimensional probabilistic cellular a