December 2006 arXiv papers — page 2

Taro Hamamoto, Kenji Kajiwara

We consider the q-Painlevé equation of type $A_4^{(1)}$ (a version of q-Painlevé V equation) and construct a family of solutions expressible in terms of certain basic hypergeometric series. We also present the determinant formula for the solutions.

Jens Hoppe

A multiparameter class of integrable systems is introduced.

K. T. Joseph, Philippe G. LeFloch

Following pioneering work by Fan and Slemrod who studied the effect of artificial viscosity terms, we consider the system of conservation laws arising in liquid-vapor phase dynamics with {\sl physical} viscosity and capillarity effects taken into account. Following Dafermos we consider self-similar solutions to the Riemann problem and establish uniform total

Robert Erdahl, Andrei Ordine, Konstantin Rybnikov

A polytope $D$ whose vertices belong to a lattice of rank $d$ is Delaunay if there is a circumscribing $d$-dimensional ellipsoid, $E$, with interior free of lattice points so that the vertices of $D$ lie on $E$. If in addition, the ellipsoid $E$ is uniquely determined by $D$, we call $D$ perfect. That is, a perfect Delaunay polytope is a lattice polytope wit

D. V. Gal'tsov, E. Yu. Melkumova, K. Salehi

We study Cerenkov radiation from moving straight strings which glisse with respect to each other in such a way that the projected intersection point moves faster than light. To calculate this effect we develop classical perturbation theory for the system of Nambu-Goto strings interacting with dilaton, two-form and gravity. In the first order one encounters d

A. S. Belyaev, I. L. Shapiro, M. A. B. do Vale

We explore the potential of the CERN Large Hadron Collider (LHC) to test the dynamical torsion parameters. The form of the torsion action can be established from the requirements of consistency of effective quantum field theory. The most phenomenologically relevant part of the torsion tensor is dual to a massive axial vector field. This axial vector has geom

Filipe Moura

We consider a d-dimensional spherically symmetric dilatonic R^2 string corrected black hole solution. We study its stability under tensor type gravitational perturbations and compute the absorption cross section for low frequency gravitational waves.

Ralf Lehnert

Small violations of spacetime symmetries have recently been identified as promising Planck-scale signals. This talk reviews how such violations can arise in various approaches to quantum gravity, how the emergent low-energy effects can be described within the framework of relativistic effective field theories, how suitable tests can be identified, and what s

Florian Catalin Popa, Ovidiu Tintareanu-Mircea

We investigate higher rank Killing-Yano tensors showing that third rank Killing-Yano tensors are not always trivial objects being possible to construct irreducible Killing tensors from them. We give as an example the Kimura IIC metric were from two rank Killing-Yano tensors we obtain a reducible Killing tensor and from third rank Killing-Yano tensors we obta

Dmitri Gal'tsov, Pavel Spirin, Simona Staub

Although consensus seems to exist about the validity of equations accounting for radiation reaction in curved space-time, their previous derivations were criticized recently as not fully satisfactory: some ambiguities were noticed in the procedure of integration of the field momentum over the tube surrounding the world-line. To avoid these problems we sugges

Dawood Kothawala, Sudipta Sarkar, T. Padmanabhan

There is an intriguing analogy between the gravitational dynamics of the horizons and thermodynamics. In case of general relativity, as well as for a wider class of Lanczos-Lovelock theories of gravity, it is possible to interpret the field equations near any spherically symmetric horizon as a thermodynamic identity TdS = dE + PdV. We study this approach fur

Christian Tanguy

The two- and all-terminal reliabilities of the Brecht-Colbourn ladder and the generalized fan have been calculated exactly for arbitrary size as well as arbitrary individual edge and node reliabilities, using transfer matrices of dimension four at most. While the all-terminal reliabilities of these graphs are identical, the special case of identical edge ($p

Jens Christian Claussen

Self-Organizing Maps are models for unsupervised representation formation of cortical receptor fields by stimuli-driven self-organization in laterally coupled winner-take-all feedforward structures. This paper discusses modifications of the original Kohonen model that were motivated by a potential function, in their ability to set up a neural mapping of maxi

Y. S. Gui, N. Mecking, X. Zhou, G. Williams

We demonstrate a room temperature spin dynamo where the precession of electron spins in ferromagnets driven by microwaves manifests itself in a collective way by generating d.c. currents. The current/power ratio is at least three orders of magnitude larger than that found previously for spin-driven currents in semiconductors. The observed bipolar nature and

A. Kreyssig, S. Chang, Y. Janssen, J. -W. Kim

X-ray diffraction experiments were performed on polycrystalline and single-crystal specimens of Ce$_{2}$Fe$_{17}$ at temperatures between 10 K and 300 K. Below $T_{\mathrm{t}}$ = 118$\pm$2 K, additional weak superstructure reflections were observed in the antiferromagnetically ordered state. The superstructure can be described by a doubling of the chemical u

Monique Combescure, Avinash Khare, Ashok Raina, Jean-Marc Richard

A presentation and a generalisation are given of the phenomenon of level rearrangement, which occurs when an attractive long-range potential is supplemented by a short-range attractive potential of increasing strength. This problem has been discovered in condensate-matter physics and has also been studied in the physics of exotic atoms. A similar phenomenon

M. B. Smirnov, M. A. Baranov

We develop a field theory approach to light propagation in a gas of resonant atoms taking into account vector character of light and atom-atom interactions. Within this approach, we calculate the propagator of the electric field for both short and long-range density-density correlation functions of the gas.

C. Scheck, L. Cheng, I. Barsukov, Z. Frait

The longest relaxation time and sharpest frequency content in ferromagnetic precession is determined by the intrinsic (Gilbert) relaxation rate \emph{$G$}. For many years, pure iron (Fe) has had the lowest known value of $G=\textrm{57 Mhz}$ for all pure ferromagnetic metals or binary alloys. We show that an epitaxial iron alloy with vanadium (V) possesses va

Shaul Mukamel

The distribution of work done on a quantum system by instantaneously changing the Hamiltonian is shown to satisfy the Jarzynski identity.

Young-Rae Kim, Rupert Croft

Using cosmological hydrodynamic simulations we measure the mean transmitted flux in the Lyman alpha forest for quasar sightlines that pass near a foreground quasar. We find that the trend of absorption with pixel-quasar separation distance can be fitted using a simple power law form including the usual correlation function parameters r_{0} and γso that (<F(r

C. Martin Gaskell

I present new comparisons of AGN optical, UV, and X-ray variations. These reveal complex relationships between the different passbands that can change with time in a given object. While there is evidence from several objects that X-ray and optical activity levels are correlated on long timescales, variations on shorter timescales can occur independently. It

C. Martin Gaskell, Andrew J. Benker, Jeffrey S. Campbell, Thomas A. George

We report on the relative optical variability of the three brightest nearby quasars, 3C 273, PDS 456, and PHL 1811. All three have comparable absolute magnitudes, but PDS 456 and PHL 1811 are radio quiet. PDS 456 is a broad-line object, but PHL 1811 could be classified as a high-luminosity Narrow-Line Seyfert 1 (NLS1). Both of the radio-quiet quasars show si

Tania Regimbau

We review the contribution of extra galactic inspiralling double neutron stars, to the LISA astrophysical gravitational wave foreground. Using recent fits of the star formation rate, we show that sources beyond $z_*=0.005$ contribute to a truly continuous background, which may dominate the LISA instrumental noise in the range $3 \simeq 10^{-4}$ - $1 \times 1

C. Lam, J. Fan

The generalized varying coefficient partially linear model with growing number of predictors arises in many contemporary scientific endeavor. In this paper we set foot on both theoretical and practical sides of profile likelihood estimation and inference. When the number of parameters grows with sample size, the existence and asymptotic normality of the prof

Veselin G. Filev, Clifford V. Johnson, R. C. Rashkov, K. S. Viswanathan

We consider a D7-brane probe of AdS$_{5}\times S^5$ in the presence of pure gauge $B$-field. In the dual gauge theory, the $B$-field couples to the fundamental matter introduced by the D7-brane and acts as an external magnetic field. The $B$-field supports a 6-form Ramond-Ramond potential on the D7-branes world volume that breaks the supersymmetry and enable

Shou-hua Zhu

The $O$(MeV) spin-1 U-boson has been proposed to mediate the interaction among electron-positron and $O$(MeV) dark matter, in order to account for the 511 keV $γ$-ray observation by SPI/INTEGRAL. In this paper the observability of such kind of U-boson at BESIII is investigated through the processes $e^+e^- \to U γ$ and $e^+e^- \to J/Ψ\to e^+e^- U$. We find t

Tommy Burch, Christian Ehmann

We analyze the overlap of local color-octet meson operators with the $Υ$ and the $η_b$ and their low-lying excited states, especially the first radial excitations. Our analysis is based on NRQCD and includes all terms up to order $v^4$. We use a variety of source and sink operators as a basis for the variational method, which enables us to clearly separate t

L. Wang, A. Rastelli, S. Kirawittaya, M. Benyoucef

We report the fabrication and photoluminescence properties of laterally-coupled GaAs/AlGaAs quantum dots. The coupling in the quantum dot molecules is tuned by an external electric field. An intricate behavior, consisting of spectral line crossings and avoided crossings is observed for different molecules. Anticrossing patterns in the photoluminescence spect

Maximilian Kreuzer

These notes contain a brief introduction to the construction of toric Calabi--Yau hypersurfaces and complete intersections with a focus on issues relevant for string duality calculations. The last two sections can be read independently and report on recent results and work in progress, including torsion in cohomology, classification issues and topological tr

Nikodem J. Poplawski

The Eddington Lagrangian in the purely affine formulation of general relativity generates the Einstein equations with the cosmological constant. The Ferraris-Kijowski purely affine Lagrangian for the electromagnetic field, which has the form of the Maxwell Lagrangian with the metric tensor replaced by the symmetrized Ricci tensor, is dynamically equivalent t

Freddy Cachazo, Marcus Spradlin, Anastasia Volovich

We introduce a method for extracting the cusp anomalous dimension at L loops from four-gluon amplitudes in N=4 Yang-Mills without evaluating any integrals that depend on the kinematical invariants. We show that the anomalous dimension only receives contributions from the obstructions introduced in hep-th/0601031. We illustrate this method by extracting the t

Olivier Maloyer, Viv Kendon

Quantum versions of random walks on the line and cycle show a quadratic improvement in their spreading rate and mixing times respectively. The addition of decoherence to the quantum walk produces a more uniform distribution on the line, and even faster mixing on the cycle by removing the need for time-averaging to obtain a uniform distribution. We calculate

Lawrence Ein, Mircea Mustata

We give a self-contained presentation of the basic results on jet schemes of singular varieties. Applications are given to invariants of singularities, such as minimal log discrepancies. We simplify our older approach to Inversion of adjunction for locally complete intersection varieties, and we prove a more general result for arbitrary Q-Gorenstein varietie

Jens Fjelstad, Jurgen Fuchs, Ingo Runkel, Christoph Schweigert

We study the sewing constraints for rational two-dimensional conformal field theory on oriented surfaces with possibly non-empty boundary. The boundary condition is taken to be the same on all segments of the boundary. The following uniqueness result is established: For a solution to the sewing constraints with nondegenerate closed state vacuum and nondegene

Christopher M. Miller, Koenraad Schalm, Erick J. Weinberg

Extremal charged black holes are BPS solutions. It is commonly thought that their nonextremal counterparts are not. Further, experience with BPS solutions in flat spacetime suggests that all BPS solutions are supersymmetric; i.e. that they are invariant under some supersymmetry charges of either the original field theory or an appropriately extended version

Filippo Viviani

We compute the infinitesimal deformations of two families of restricted simple modular Lie algebras of Cartan type: the Witt-Jacobson and the Special Lie algebras.

Eric Falcon, Stéphan Fauve, Claude Laroche

We report the observation of intermittency in gravity-capillary wave turbulence on the surface of mercury. We measure the temporal fluctuations of surface wave amplitude at a given location. We show that the shape of the probability density function of the local slope increments of the surface waves strongly changes across the time scales. The related struct

Thomas Curtright, Evgeny Ivanov, Luca Mezincescu, Paul K. Townsend

We use the methods of PT-symmetric quantum theory to find a one-parameter family of ISU(1|1)-invariant planar super-Landau models with positive norm, uncovering an `accidental', and generically spontaneously-broken, worldline supersymmetry, with charges that have a Sugawara-type representation in terms of the ISU(1|1) charges. In contrast to standard models

Binod Kumar Sahoo, N. S. Narasimha Sastry

This paper has been withdrawn as the statements in Proposition 4.4 and Theorem 1.4(i) are not correct.

A. A. Tseytlin

Zamolodchikov&#39;s c-theorem type argument (and also string theory effective action constructions) imply that the RG flow in 2d sigma model should be gradient one to all loop orders. However, the monotonicity of the flow of the target-space metric is not obvious since the metric on the space of metric-dilaton couplings is indefinite. To leading (one-loop) o

Beatriz Gato-Rivera

I review the main features of the Dijkstra-Huiszoon-Schellekens (DHS) orientifolds and report on the search for global anomalies that Schellekens and the author have performed for these models.

Ian-Woo Kim, Jihn E. Kim, Bumseok Kyae

In a recent $\Z_{12-I}$ orbifold model, an approximate $Z_2$ symmetry which forbids the baryon number violating operators up to sufficiently high orders is found. The dimension-4 $ΔB\ne 0$ operators of the MSSM fields occur at dimension 10. The effective dimension-5 $ΔB\ne 0$ operators derived from these are harmless if some VEVs of neutral singlets are O(1/

Davide Gaiotto, Lisa Huang

We consider D4-branes on toric Calabi-Yau spaces. The quiver gauge theory that describes several D4-branes on the Calabi-Yau has a Higgs branch, that describes configurations of a single large D4-brane with the same charges. We propose that the world volume of such a D4-brane is described by a determinantal variety. We discuss a description of the Higgs bran

Slavko Bogdanov, George B. Rybicki, Jonathan E. Grindlay

We present a model of thermal X-ray emission from hot spots on the surface of a rotating compact star with an unmagnetized light-element atmosphere. An application to ROSAT, Chandra, and XMM-Newton X-ray observations of the nearest known rotation-powered millisecond pulsar (MSP) PSR J0437--4715 reveals that the thermal emission from this pulsar is fully cons

Klaus Fabricius, Barry M. McCoy

Whereas the tools to determine the eigenvalues of the eight-vertex transfer matrix T are well known there has been until recently incomplete knowledge about the eigenvectors of T. We describe the construction of eigenvectors of T corresponding to degenerate eigenvalues and discuss the related hidden elliptic symmetry.

Jianqing Fan, Jinchi Lv

Variable selection plays an important role in high dimensional statistical modeling which nowadays appears in many areas and is key to various scientific discoveries. For problems of large scale or dimensionality $p$, estimation accuracy and computational cost are two top concerns. In a recent paper, Candes and Tao (2007) propose the Dantzig selector using $

Bobby S. Acharya, Suresh Govindarajan, Chethan N. Gowdigere

Stationary, supersymmetric supergravity solutions in five dimensions have Kahler metrics on the four-manifold orthogonal to the orbits of a time-like Killing vector. We show that an explicit class of toric Kahler metrics provide a unified framework in which to describe both the asymptotically flat and asymptotically AdS solutions. The Darboux co-ordinates us

Daniele Oriti

We present the case for a fundamentally discrete quantum spacetime and for Group Field Theories as a candidate consistent description of it, briefly reviewing the key properties of the GFT formalism. We then argue that the outstanding problem of the emergence of a continuum spacetime and of General Relativity from fundamentally discrete quantum structures sh

John D. Barrow

We introduce some early considerations of physical and mathematical impossibility as preludes to the Goedel incompleteness theorems. We consider some informal aspects of these theorems and their underlying assumptions and discuss some the responses to these theorems by those seeking to draw conclusions from them about the completability of theories of physic

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli

Aiming at absolute force calibration of optical tweezers, following a critical review of proposed theoretical models, we present and test the results of MDSA (Mie-Debye-Spherical Aberration) theory, an extension of a previous (MD) model, taking account of spherical aberration at the glass/water interface. This first-principles theory is formulated entirely i

D. Klochkov, N. Shakura, K. Postnov, R. Staubert

We have performed an analysis and interpretation of the X-ray light curve of the accreting neutron star Her X-1 obtained with the ASM RXTE over the period 1996 February to 2004 September. The averaged X-ray light curves are constructed by means of adding up light curves corresponding to different 35 day cycles. A numerical model is introduced to explain the

E. Izadi

We describe an inductive approach most appropriate for abelian varieties with an action of an imaginary quadratic field.

V. V. Gribanov

It is shown that the one-dimensional generalized N=4 supersymmetric Toda lattice (TL) hierarchy (nlin.Si/0311030) contains the N=4 super-KdV hierarchy with the first flow time in the role of space coordinate. Two different N=2 superfield forms of the generalized N=4 supersymmetric TL equation, which are useful when solving the N=4 super-KdV and (1,1)-GNLS hi

P. Esposito, S. Mereghetti, A. Tiengo, D. Goetz

We present a systematic analysis of all the BeppoSAX data of SGR 1900+14. The observations spanning five years show that the source was brighter than usual on two occasions: ~20 days after the August 1998 giant flare and during the 10^5 sec long X-ray afterglow following the April 2001 intermediate flare. In the latter case, we explore the possibility of des

N. Ahmadi, S. Khoeini-Moghaddam, M. Nouri-Zonoz

Interactions incorporating the vacuum polarization effects in curved backgrounds modify the null cone structure in such a way that the photon trajectories would not be the space-time geodesics anymore. The gravitational birefringence introduced as a direct consequence of these effects, will allow shifts in the photon velocities leading to polarization depend

S. -G. Kim, N. Maekawa, A. Matsuzaki, K. Sakurai

We analyze lepton flavor violating $τ\to μγ$ and $μ\to e γ$ processes in SUSY GUT model in which sfermions have special mass spectrum. It is assumed that only third generation sfermions which are contained in ${\bf 10}(Q, U^c, E^c)$ of SU(5) can have a different mass from the others. This mass spectrum is led from $E_6$ GUT model with horizontal symmetries.

O. L. Muskens, J. Gomez Rivas, V. Giannini, J. A. Sanchez-Gil

We investigate the far-field optical resonances of individual dimer nanoantennas using confocal scattering spectroscopy. Experiments on a single-antenna array with varying arm lengths and interparticle gap sizes show large spectral shifts of the plasmon modes due to a combination of geometrical resonances and plasmon hybridization. All resonances are conside

Yoshiharu Tanaka, Misao Sasaki

Using the gradient expansion approach, we formulate a nonlinear cosmological perturbation theory on super-horizon scales valid to $O(ε^2)$, where $ε$ is the expansion parameter associated with a spatial derivative. For simplicity, we focus on the case of a single perfect fluid, but we take into account not only scalar but also vector and tensor modes. We der

Paul Boddington

For $n\geq 4$ we shall construct a family $D(q)$ of non-commutative deformations of the coordinate algebra of a Kleinian singularity of type $D_n$ depending on a polynomial $q$ of degree $n$. We shall prove that every deformation of a type $D$ Kleinian singularity which is not commutative is isomorphic to some $D(q)$. We shall then consider in type $D$ the f

Spiros Cotsakis, Antonios Tsokaros

It was shown long ago by T. V. Ruzmaikina and A. A. Ruzmaikin that within the framework of a homogeneous and isotropic cosmological model quadratic corrections of the gravitational field cannot provide solutions that are both regular initially and go over to Friedmann type at later times. We find here, by applying a dynamical systems approach, the general fo

Robert Beig, Bernd G. Schmidt

We construct time independent configurations of two gravitating elastic bodies. These configurations either correspond to the two bodies moving in a circular orbit around their center of mass or strictly static configurations.

Stavros Christofi, Costas Strouthos

We present results from numerical simulations of three different 3d four-fermion models that exhibit Z_2, U(1), and SU(2) x SU(2) chiral symmetries, respectively. We performed the simulations by using the hybrid Monte Carlo algorithm. We employed finite size scaling methods on lattices ranging from 8^3 to 40^3 to study the properties of the second order chir

Viviane Baladi

We study the susceptibility function Psi(z) associated to the perturbation f_t=f+tX of a piecewise expanding interval map f. The analysis is based on a spectral description of transfer operators. It gives in particular sufficient conditions which guarantee that Psi(z) is holomorphic in a disc of larger than one. Although Psi(1) is the formal derivative of th

Zheng-Cheng Gu, Zheng-Yu Weng

An understanding of the anomalous charge dynamics in the high-Tc cuprates is obtained based on a model study of doped Mott insulators. The high-temperature optical conductivity is found to generally have a two-component structure: a Drude like part followed by a mid-infrared band. The scattering rate associated with the Drude part exhibits a linear-temperatu

Patrick Dorey, Clare Dunning, Davide Masoero, Junji Suzuki

The correspondence between ordinary differential equations and Bethe ansatz equations for integrable lattice models in their continuum limits is generalised to vertex models related to classical simple Lie algebras. New families of pseudo-differential equations are proposed, and a link between specific generalised eigenvalue problems for these equations and

S. V. Demidov, D. S. Gorbunov

We present an extension of the minimal split supersymmetry model, which is capable of explaining the baryon asymmetry of the Universe. Instead of MSSM we start from NMSSM and split its spectrum in such a way that the low energy theory contains neutral particles, in addition to the content of minimal split supersymmetry. They trigger the strongly first order

Dong Pyo Chi, Jeong Woon Choi, Jeong San Kim, Taewan Kim

In this paper, we present sufficient conditions for states to have positive distillable key rate. Exploiting the conditions, we show that the bound entangled states given by Horodecki et al. [Phys. Rev. Lett. 94, 160502 (2005), quant-ph/0506203] have nonzero distillable key rate, and finally exhibit a new class of bound entangled states with positive distill

F. Hassler, G. B. Lesovik, G. Blatter

We study the full counting statistics for the transmission of two identical particles with positive or negative symmetry under exchange for the situation where the scattering depends on energy. We find that, besides the expected sensitivity of the noise and higher cumulants, the exchange symmetry has a huge effect on the average transmitted charge; for equal

HuJun Jiao, Xin-Qi Li, JunYan Luo

Owing to a few unique advantages, double-dot single electron transistor has been proposed as an alternative detector for charge states. In this work, we present a further study for its signal-to-noise property, based on a full analysis of the setup configuration symmetry. It is found that the effectiveness of the double-dot detector can approach that of an i

Anirban Saha, Anisur Rahaman, Pradip Mukherjee

This paper has been withdrawn by the author(s), because it contains erroneous conclusion. Some part of the contents of the paper may be used in a future communication.

Alexander Burinskii

The Dirac theory of electron and QED neglect gravitational field, while the corresponding to electron Kerr-Newman gravitational field has very strong influence on the Compton distances. It polarizes space-time, deforms the Coulomb field and changes topology. We argue that the Kerr geometry may be hidden beyond the Quantum Theory, representing a complimentary

Alexander Burinskii

Aligned to the Kerr-Schild geometry electromagnetic excitations are investigated, and asymptotically exact solutions are obtained for the low-frequency limit.

Anirudh Pradhan, Vandana Rai, R. S. Singh

Bianchi type V bulk viscous fluid cosmological models are investigated. Using a generation technique (Camci {\it et al.}, 2001), it is shown that the Einstein&#39;s field equations are solvable for any arbitrary cosmic scale function. The viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density. Solutions for particular f

Juergen Herzog, Ali Soleyman Jahan, Siamak Yassemi

We study Stanley decompositions and show that Stanley&#39;s conjecture on Stanley decompositions implies his conjecture on partitionable Cohen-Macaulay simplicial complexes. We also prove these conjectures for all Cohen-Macaulay monomial ideals of codimension 2 and all Gorenstein monomial ideals of codimension 3.

Pavel Exner, Mario Helm, Peter Stollmann

We prove spectral and dynamical localization on a cubic-lattice quantum graph with a random potential. We use multiscale analysis and show how to obtain the necessary estimates in analogy to the well-studied case of random Schroedinger operators.

M. Krips, A. Eckart, T. P. Krichbaum, J. -U. Pott

We present high angular resolution radio snap-shot observations of seven nearby low-luminosity active galaxies (LLAGN) from the NUclei of GAlaxies (NUGA) survey. The observations were conducted with MERLIN and EVN/VLBI at 18cm and 6cm. At all observed angular resolutions and frequencies, we find indications for extended emission in about ~40% of the sources,

Jae-Hoon Kwon

In this paper, we present a simple combinatorial proof of a Weyl type formula for hook Schur polynomials, which has been obtained by using a Kostant type cohomology formula for $\frak{gl}_{m|n}$. In general, we can obtain in a combinatorial way a Weyl type formula for various highest weight representations of a Lie superalgebra, which together with a general

Ali Mohammad Nassimi, Gholamabbas Parsafar

The interaction potential energy among particles in many systems is of the form of r^-(alpha), at least at long distances. It has been argued that, in systems for which (alpha) < d (d is the space dimension) we encounter with nonextensive (nonintensive) thermodynamic functions. A scaling parameter N~ has been introduced to make nonextensive (nonintensive) th

J. Brian Conrey, David W. Farmer, Jon P. Keating, Michael O. Rubinstein

We describe an algorithm for obtaining explicit expressions for lower terms for the conjectured full asymptotics of the moments of the Riemann zeta function, and give two distinct methods for obtaining numerical values of these coefficients. We also provide some numerical evidence in favour of the conjecture.

Hidenori Sonoda

We discuss how the ordinary renormalization group (RG) equations arise in the context of Wilson&#39;s exact renormalization group (ERG) as formulated by Polchinski. We consider the phi4 theory in four dimensional euclidean space as an example, and introduce a particular scheme of parameterizing the solutions of the ERG equations. By analyzing the scalar comp

Hadley M. Lawler, Jason N. Byrd, Gavin K. Brennen

We present the theory of interaction between a polar vibration in a semiconductor and an electromagnetic mode of a surrounding cavity. Tuning the cavity frequency near the transverse optical phonon frequency couples the phonon-induced polarization field within the dielectric and the electromagnetic field in the cavity. Depending on engineering parameters, we

Tsuyoshi Inoue, Shu-ichiro Inutsuka, Hiroshi Koyama

We investigate the dynamical condensation process in a magnetized thermally bistable medium. We perform one-dimensional two fluid numerical simulations that describe the neutral and ionized components in the interstellar medium with purely transverse magnetic fields. We find that the clouds that are formed as a consequence of the thermal instability always h

S. K. Ozdemir, A. Miranowicz, T. Ota, G. Yusa

Coherent oscillations between any two levels from four nuclear spin states of I=3/2 have been demonstrated in a nanometre-scale NMR semiconductor device, where nuclear spins are all-electrically controlled. Using this device, we discuss quantum logic operations on two fictitious qubits of the I=3/2 system, and propose a quantum state tomography scheme based

Graciela Domenech, Hector Freytes, Christian de Ronde

Kochen-Specker theorem rules out the non-contextual assignment of values to physical magnitudes. Here we enrich the usual orthomodular structure of quantum mechanical propositions with modal operators. This enlargement allows to refer consistently to actual and possible properties of the system. By means of a topological argument, more precisely in terms of

Graciela Domenech, Hector Freytes, Christian de Ronde

We develop an algebraic frame for the simultaneous treatment of actual and possible properties of quantum systems. We show that, in spite of the fact that the language is enriched with the addition of a modal operator to the orthomodular structure, contextuality remains a central feature of quantum systems.

Tulsi Dass

Supmech, an algebraic scheme of mechanics integrating noncommutative symplectic geometry and noncommutative probability, subsumes quantum and classical mechanics and permits consistent treatment of interaction of quantum and classical systems. Quantum measurements are treated in this framework; the von Neumann reduction rule (generally postulated) is derived

Wen-Ling Chan, Jun-Peng Cao, Dong Yang, Shi-Jian Gu

We quantify the total, quantum, and classical correlations with entropic measures, and quantitatively compare these correlations in a quantum system, as exemplified by a Heisenberg dimer which is subjected to the change of environmental parameters: temperature and nonuniform external field. Our results show that the quantum correlation may exceed the classic

Ilya Nemenman, Geoffrey D. Lewen, William Bialek, Rob R. de Ruyter van Steveninck

Our knowledge of the sensory world is encoded by neurons in sequences of discrete, identical pulses termed action potentials or spikes. There is persistent controversy about the extent to which the precise timing of these spikes is relevant to the function of the brain. We revisit this issue, using the motion-sensitive neurons of the fly visual system as a t

E. Narevicius, A. Libson, M. F. Riedel, C. G. Parthey

We report the slowing of a supersonic beam by elastic reflection from a receding atomic mirror. We use a pulsed supersonic nozzle to generate a 511 +/- 9 m/s beam of helium that we slow by reflection from a Si(111)-H(1x1) crystal placed on the tip of a spinning rotor. We were able to reduce the velocity of helium by 246 m/s and show that the temperature of t

J. Becker, K. Bösiger, L. Lindfeld, K. Müller

The article describes the technical implementation and the performance of the z-vertex trigger (CIP2k), which is part of the H1-experiment at HERA.

M. Di Marco, P. Peiffer, S. Schönert

Measurements with a bare p-type high purity germanium diode (HPGe) submerged in a 19 kg liquid argon (LAr) scintillation detector at MPIK Heidelberg are reported. The liquid argon--germanium system (LArGe) is operated as a 4$π$ anti-Compton spectrometer to suppress backgrounds in the HPGe. This R&D is carried out in the framework of the GERDA experiment whic

Abdelaziz Mhirech, Assia Alaoui Ismaili, Hamid Ez-Zahraouy

The effect of one on-ramp (entry) and one off-ramp (exit) is investigated numerically in one dimensional-cellular automaton traffic flow model, with open boundary conditions, using parallel dynamics. Our aim in this paper is to study how the injecting rates $α$ and $α_{0}$ and the extracting rates $β$ and $β_{0}$ acts on the density and flux of cars in one d

U. D. Jentschura

Two-loop Bethe logarithms are calculated for excited P and D states in hydrogenlike systems, and estimates are presented for all states with higher angular momenta. These results complete our knowledge of the P and D energy levels in hydrogen at the order of alpha^8 m_e c^2, where m_e is the electron mass and c is the speed of light, and scale as Z^6, where

Chun Wa Wong, Seo Ho Youn, Kosuke Yasui

A uniform, flexible and frictionless chain falling link by link from a heap by the edge of a table falls with an acceleration $g/3$ if the motion is nonconservative, but $g/2$ if the motion is conservative, $g$ being the acceleration due to gravity. Unable to construct such a falling chain, we use instead higher-dimensional versions of it. A home camcorder i

Yoshiko Kanada-En&#39;yo

The negative parity states of $^{11}$B and $^{11}$C were studied based on the calculations of antisymmetrized molecular dynamics(AMD). The calculations well reproduced the experimental strengths of Gamov-Teller(GT), $M1$ and monopole transitions. We, especially, focused on the $3/2^-_3$ and $5/2^-_2$ states, for which GT transition strengths were recently me

M. Bruno, F. Gulminelli, F. Cannata, M. D&#39;Agostino

Signals of bimodality have been investigated in experimental data of quasi-projectile decay produced in Au+Au collisions at 35 AMeV. This same data set was already shown to present several signals characteristic of a first order, liquid-gas-like phase transition. For the present analysis, events are sorted in bins of transverse energy of light charged partic

Annalisa M. Calini, Thomas A. Ivey

We study the topology of quasiperiodic solutions of the vortex filament equation in a neighborhood of multiply covered circles. We construct these solutions by means of a sequence of isoperiodic deformations, at each step of which a real double point is &#34;unpinched&#34; to produce a new pair of branch points and therefore a solution of higher genus. We pr

Jon Links, Katrina E. Hibberd

The Bose-Hubbard dimer Hamiltonian is a simple yet effective model for describing tunneling phenomena of Bose-Einstein condensates. One of the significant mathematical properties of the model is that it can be exactly solved by Bethe ansatz methods. Here we review the known exact solutions, highlighting the contributions of V.B. Kuznetsov to this field. Two

J. Fan, P. Hall, Q. Yao

In the analysis of microarray data, and in some other contemporary statistical problems, it is not uncommon to apply hypothesis tests in a highly simultaneous way. The number, $ν$ say, of tests used can be much larger than the sample sizes, $n$, to which the tests are applied, yet we wish to calibrate the tests so that the overall level of the simultaneous t

Antonio Campillo, Gert-Martin Greuel, Christoph Lossen

In this paper we develop the theory of equisingular deformations of plane curve singularities in arbitrary characteristic. We study equisingular deformations of the parametrization and of the equation and show that the base space of its semiuniveral deformation is smooth in both cases. Our approach through deformations of the parametrization is elementary an