September 2007 arXiv papers — page 21

Andrew Randono

The Kodama state is unique in being an exact solution to all the constraints of quantum gravity that also has a well defined semi-classical interpretation as the quantum version of a classical spacetime, namely de Sitter or anti-de sitter space. Despite this, the state fails to pass some of the key tests of a physically realistic quantum state. In an attempt

S. Schadmand

The question of the origin of hadron masses is one major issue in the understanding of the strong interaction. The challenge is addressed by searching for indications of in-medium modifications of hadron properties and studying hadrons in nuclei. The quest driving in-medium studies is to understand the origin of hadron masses in the context of spontaneous ch

Yuri Reyes-Mercado, Francisco J. Rodriguez-Gomez, Yurko Duda

Acrylic acid (AA) is a monomer commonly employed in emulsion polymerization to provide electrostatic colloidal stability and improve specific film performance. The addition of AA not only modifies the kinetics of the polymerization, but also it takes part in the interaction between colloidal particles, which has a strong influence on their packing and conseq

Liljana Babinkostova, Marion Scheepers

The product of a Sierpinski set and a Lusin set has Menger's property. The product of a gamma set and a Lusin set has Rothberger's property.

Liljana Babinkostova, Marion Scheepers

We characterize countable dimensionality and strong countable dimensionality by means of an infinite game.

A. H. Prestwich, R. Kilgard, P. A. Crowther, S. Carpano

IC 10 X-1 is a bright (Lx=10^38 ergs/s) variable X-ray source in the local group starburst galaxy IC 10. The most plausible optical counterpart is a luminous Wolf-Rayet star, making IC 10 X-1 a rare example of a Wolf-Rayet X-ray binary. In this paper, we report on the detection of an X-ray orbital period for IC 10 X-1of 34.4 hours. This result, combined with

Thomas DeGrand, Stefan Schaefer

We recently performed a pilot study determining the parameters of the leading order chiral Lagrangian from distributions of the eigenvalues of a quenched Dirac operator coupled to an imaginary isospin chemical potential. We complement a quick survey of our recent preprint arXiv:0708.1731 [hep-lat] by addressing some points raised during discussions at the co

P. Hennebelle, R. Teyssier

Abridged. A large fraction of stars are found in binary systems. It is therefore important for our understanding of the star formation process, to investigate the fragmentation of dense molecular cores. We study the influence of the magnetic field, ideally coupled to the gas, on the fragmentation in multiple systems of collapsing cores. We present high resol

P. Hennebelle, S. Fromang

Abridged. It is important for the star formation process to understand the collapse of a prestellar dense core. We investigate the effect of the magnetic field during the first collapse up to the formation of the firstcore, focusing particularly on the magnetic braking and the launching of outflows. We perform 3D AMR high resolution numerical simulations of

L. Dinis, E. M. Gonzalez, J. V. Anguita, J. M. R. Parrondo

Competition between the vortex lattice and a lattice of asymmetric artificial defects is shown to play a crucial role in ratchet experiments in superconducting films. We present a novel and collective mechanism for current reversal based on a reconfiguration of the vortex lattice. In contrast to previous models of vortex current reversal, the mechanism is ba

Tanju Gleisberg, Frank Krauss

In this publication the construction of an automatic algorithm to subtract infrared divergences in real QCD corrections through the Catani-Seymour dipole subtraction method [arXiv:hep-ph/9605323] is reported. The resulting computer code has been implemented in the matrix element generator AMEGIC++ [arXiv:hep-ph/0109036]. This will allow for the automatic gen

J. Rho, T. Kozasa, W. T. Reach, L. Rudnick

We performed Spitzer Infrared Spectrograph mapping observations covering nearly the entire extent of the Cassiopeia A supernova remnant (SNR), producing mid-infrared (5.5-35 micron) spectra every 5-10". Gas lines of Ar, Ne, O, Si, S and Fe, and dust continua were strong for most positions. We identify three distinct ejecta dust populations based on their

Mónica Clapp, Claudio Muñoz, Monica Musso

Let $Ω$ be a bounded smooth domain in $\mathbb{R}^{4}$ such that for some integer $d\geq1$ its $d$-th singular cohomology group with coefficients in some field is not zero, then problem {Δ^{2}u-ρ^{4}k(x)e^{u}=0 & \hbox{in}Ω, u=Δu=0 & \hbox{on}\partialΩ, has a solution blowing-up, as $ρ\to0$, at $m$ points of $Ω$, for any given number $m$.

Einan Gardi, Georges Grunberg

We present a general all-order formulation of Sudakov resummation in QCD in terms of dispersion integrals. We show that the Sudakov exponent can be written as a dispersion integral over spectral density functions, weighted by characteristic functions that encode information on power corrections. The characteristic functions are defined and computed analytica

E. J. Sambriski, M. G. Guenza

A microscopic theory for coarse graining diblock copolymers into dumbbells of interacting soft colloidal particles has been developed, based on the solution of liquid-state integral equations. The Ornstein-Zernike equation is solved to provide a mesoscopic description of the diblock copolymer system at the level of block centers of mass, and at the level of

A. V. Nefiodov, G. Plunien

We have considered the processes of excitation and ionization of light multicharged ions by impact of high-energy particles, which proceed with participation of the $ns$ electrons. The screening corrections to the energy levels and photoionization cross sections are evaluated analytically within the framework of the non-relativistic perturbation theory with

O. Scholten, K. Werner, F. Rusydi

We have developed a macroscopic description of coherent electro-magnetic radiation from air showers initiated by ultra-high energy cosmic rays due to the presence of the geo-magnetic field. This description offers a simple and direct insight in the relation between the properties of the air shower and the time-structure of the radio pulse.

Marcos Lima, Wayne Hu

The ability to constrain dark energy from the evolution of galaxy cluster counts is limited by the imperfect knowledge of cluster redshifts. Ongoing and upcoming surveys will mostly rely on redshifts estimated from broad-band photometry (photo-z's). For a Gaussian distribution for the cluster photo-z errors and a high cluster yield cosmology defined by t

Smita Mathur, Gregory R. Sivakoff, Rik J. Williams, Fabrizio Nicastro

Absorption lines of OVII at redshift zero are observed in high quality Chandra spectra of extragalactic sightlines. The location of the absorber producing these lines, whether from the corona of the Galaxy or from the Local Group or even larger scale structure, has been a matter of debate. Here we study another poor group like our Local Group to understand t

A. V. Nefiodov, G. Plunien

The universal scaling behavior for the electron-impact excitation cross sections of the $2s$ states of hydrogen- and helium-like multicharged ions is deduced. The study is performed within the framework of non-relativistic perturbation theory, taking into account the one-photon exchange diagrams. Special emphasis is laid on the near-threshold energy domain.

Oz Ben-Shimol

Let $f$ be an irreducible polynomial of prime degree $p\geq 5$ over $\QQ$, with precisely $k$ pairs of complex roots. Using a result of Jens Höchsmann (1999), we show that if $p\geq 4k+1$ then $\Gal(f/\QQ)$ is isomorphic to $A_{p}$ or $S_{p}$. This improves the algorithm for computing the Galois group of an irreducible polynomial of prime degree, introduced

F. Mueller, S. Heugel, L. J. Wang

We observe the opto-mechanical multistability of a macroscopic torsion balance oscillator. The torsion oscillator forms the moving mirror of a hemi-spherical laser light cavity. When a laser beam is coupled into this cavity, the radiation pressure force of the intra-cavity beam adds to the torsion wire's restoring force, forming an opto-mechanical potent

I. Papadopoulos, P. Wagner, G. Wunner, J. Main

Amplifying on a proposal by O'Dell et al. for the realization of Bose-Einstein condensates of neutral atoms with attractive $1/r$ interaction, we point out that the instance of self-trapping of the condensate, without external trap potential, is physically best understood by introducing appropriate "atomic" units. This reveals a remarkable scalin

Michael C. Birse

This lecture provides an introduction to the renormalisation group as applied to scattering of two nonrelativistic particles. As well as forming a framework for constructing effective theories of few-nucleon systems, these ideas also provide a simple example which illustrates general features of the renormalisation group.

Robert B. Palmer, J. Scott Berg, Richard C. Fernow, Juan Carlos Gallardo

A complete scheme for production, cooling, acceleration, and ring for a 1.5 TeV center of mass muon collider is presented, together with parameters for two higher energy machines. The schemes starts with the front end of a proposed neutrino factory that yields bunch trains of both muon signs. Six dimensional cooling in long-period helical lattices reduces th

H. -J. Mikeska, C. Luckmann

We present results on the dynamics of the distorted diamond chain, S=1/2 dimers alternating with single spins 1/2 and exchange couplings $J_1$ and $J_3$ in between. The dynamics in the spin fluid (SF) and tetramer-dimer (TD) phases is investigated numerically by exact diagonalisation for up to 24 spins. Representative excitation spectra are presented, both f

M. Cappellari, R. Bacon, R. L. Davies, P. T. de Zeeuw

Supermassive black holes are a key element in our understanding of how galaxies form. Most of the progress in this very active field of research is based on just ~30 determinations of black hole mass, accumulated over the past decade. We illustrate how integral-field spectroscopy, and in particular our OASIS modeling effort, can help improve the current situ

Paolo Rossi

We compute the Gromov-Witten potential at all genera of target smooth Riemann surfaces using Symplectic Field Theory techniques and establish differential equations for the full descendant potential. This amounts to impose (and possibly solve) different kinds of Schroedinger equations related to some quantization of the dispersionless KdV hierarchy. In parti

K. O. Eyser, C. Helebrant, D. Kaefer, J. List

High energy longitudinal electron polarimetry will be based on Compton scattering for the International Linear Collider. An unobtrusive measurement has to include a magnet chicane setup serving as a spectrometer. Current proposals make use of Cerenkov detectors for electron detection. A fast simulation has been developed to study the basic properties of scen

Y. Pan, N. Jiang, J. T. Sun, D. X. Shi

We demonstrate a method for synthesizing large scale single layer graphene by thermal annealing of ruthenium single crystal containing carbon. Low energy electron diffraction indicates the graphene grows to as large as millimeter dimensions with good long-range order, and scanning tunneling microscope shows perfect crystallinity. Analysis of Moire pattern au

Anthony A. Ruffa

A set of equations is developed to describe a curve in space given the curvature $κ$ and the angle of rotation $θ$ of the osculating plane. The set of equations has a solution (in terms of $κ$ and $θ$) that indirectly solves the Frenet-Serret equations, with a unique value of $θ$ for each specified value of $τ$. Explicit solutions can be generated for consta

R. Hodgson, I. Jack, D. R. T. Jones

We address renormalisation group evolution issues that arise in the Anomaly Mediated Supersymmetry Breaking scenario when the tachyonic slepton problem is resolved by Fayet-Iliopoulos term contributions. We present typical sparticle spectra both for the original formulation of this idea and an alternative using Fayet-Iliopoulos terms for a U(1) compatible wi

M. Wagenknecht, D. Koelle, R. Kleiner, S. Graser

We investigate in-plane quasiparticle tunneling across thin film grain boundary junctions (GBJs) of the electron-doped cuprate La$_{2-x}$Ce$_{x}$CuO$_4$ in magnetic fields up to $B=16 $T, perpendicular to the CuO$_2$ layers. The differential conductance in the superconducting state shows a zero bias conductance peak (ZBCP) due to zero energy surface Andreev

David Gesbert, Marios Kountouris

We address the optimization of the sum rate performance in multicell interference-limited singlehop networks where access points are allowed to cooperate in terms of joint resource allocation. The resource allocation policies considered here combine power control and user scheduling. Although very promising from a conceptual point of view, the optimization o

Leonardo Spanu, Massimo Lugas, Federico Becca, Sandro Sorella

We present a systematic study of the phase diagram of the $t{-}t^\prime{-}J$ model by using the Green's function Monte Carlo (GFMC) technique, implemented within the fixed-node (FN) approximation and a wave function that contains both antiferromagnetic and d-wave pairing. This enables us to study the interplay between these two kinds of order and compare

C. J. Wareing, Albert A. Zijlstra, T. J. O'Brien

Interaction with the Interstellar Medium (ISM) cannot be ignored in understanding planetary nebula (PN) evolution and shaping. In an effort to understand the range of shapes observed in the outer envelopes of PNe, we have run a comprehensive set of three-dimensional hydrodynamic simulations, from the beginning of the asymptotic giant branch (AGB) superwind p

M. A. Korshunov

Dependence of frequency spectra of the lattice oscillations of organic nano-crystals on temperature is studied at presence of vacancies in structure. In a frequency spectrum a number of additional lines monotonously changing with temperature is observed. Also, the spectrum of the surface oscillations is calculated at temperature change. At the same time, the

M. A. Korshunov

Calculations of frequencies of the lattice and surface oscillations of organic nano-crystals are carried out. As the sample the para-dichlorobenzol has been chosen. Change of spectra of oscillations from the sizes of nano-particles is found. It is shown that with the reduction of the sizes of nano-particles a spectrum of the surface oscillations prevailing.

M. A. Korshunov

Calculations of frequency spectra for organic molecular crystals taking various defects in their structure into account are carried out. It is shown how the presence of the vacancies, orientation disorder, and surface presence affects spectra. It was found, that each defect has the characteristic set of lines in the spectra.

Y. Hosotani, N. Maru, K. Takenaga, Toshifumi Yamashita

The zero mode of an extra-dimensional component of gauge potentials serves as a 4D Higgs field in the gauge-Higgs unification. We examine QED on $M^4 \times S^1$ and determine the mass and potential of a 4D Higgs field (the $A_5$ component) at the two loop level with gauge invariant reguralization. It is seen that the mass is free from divergences and indepe

John Palmeri, Manoel Manghi, Nicolas Destainville

Statistical DNA models available in the literature are often effective models where the base-pair state only (unbroken or broken) is considered. Because of a decrease by a factor of 30 of the effective bending rigidity of a sequence of broken bonds, or bubble, compared to the double stranded state, the inclusion of the molecular conformational degrees of fre

J. L. Jaramillo, E. Gourgoulhon, I. Cordero-Carrion, J. M. Ibanez

We present a set of inner boundary conditions for the numerical construction of dynamical black hole space-times, when employing a 3+1 constrained evolution scheme and an excision technique. These inner boundary conditions are heuristically motivated by the dynamical trapping horizon framework and are enforced in an elliptic subsystem of the full Einstein eq

Olivier Morizot, Carlos L. Garrido Alzar, Paul-Eric Pottie, Vincent Lorent

We observe the spontaneous evaporation of atoms confined in a bubble-like rf-dressed trap (Zobay and Garraway, 2001). The atoms are confined in a quadrupole magnetic trap and are dressed by a linearly polarized rf field. The evaporation is related to the presence of holes in the trap, at the positions where the rf coupling vanishes, due to its vectorial char

Motoi Endo

We show that the anomaly-mediated supersymmetry breaking via the Kahler and sigma-model anomalies is suppressed by conformal dynamics in the supersymmetry breaking sector.

S. Moehler, S. Dreizler, T. Lanz, G. Bono

UV observations of some massive globular clusters uncovered a significant population of very hot stars below the hot end of the horizontal branch (HB), the so-called blue hook stars. This feature might be explained either as results of the late hot flasher scenario where stars experience the helium flash while on the white dwarf cooling curve or by the proge

Bruno Angles

In this paper we give a bound for the Iwasawa lambda invariant of an abelian number field attached to the cyclotomic Z_p-extension of that field. We also give some properties of Iwaswa power series attached to p-adic L-functions.

A. Bamberger, K. Desch, U. Renz, M. Titov

This contribution investigates a prototype of a TPC readout with a highly pixelated CMOS ASIC, which is an option for charged particles tracking of the ILC. A triple GEM stack was joined with a TimePix and MediPix2 chip (pixel size of 55$\times$55 $μm^2$) and its readout properties were investigated with 5 GeV electrons. The spatial resolution of the cluster

Jan Forbrich, Thomas Preibisch

In order to study the X-ray properties of young stellar objects (YSOs), we analyze an exceptionally sensitive Chandra dataset of the Coronet cluster in the CrA star-forming region, achieving a limiting luminosity of LXmin=5E26 erg/sec for lightly absorbed sources. This dataset represents one of the most sensitive X-ray observations ever obtained of a star-fo

Benedykt R. Jany

The article describes experimental status of EtaPrime->Pi+Pi-Eta and EtaPrime->Pi+Pi-Pi0 decays. A theoretical framework used for description of the decays mechanism is also reviewed. The possibilities for the measurements with WASA-at-COSY are mentioned.

G. Susinder Rajan, B. Sundar Rajan

Recently Li and Xia have proposed a transmission scheme for wireless relay networks based on the Alamouti space time code and orthogonal frequency division multiplexing to combat the effect of timing errors at the relay nodes. This transmission scheme is amazingly simple and achieves a diversity order of two for any number of relays. Motivated by its simplic

Katrin Gelfert, Michal Rams

We study the Hausdorff dimension spectrum for Lyapunov exponents for a class of interval maps which includes several non-hyperbolic situations. We also analyze the level sets of points with given lower and upper Lyapunov exponents and, in particular, with zero lower Lyapunov exponent. We prove that the level set of points with zero exponent has full Hausdorf

Hanqing Jin, Xunyu Zhou

This paper formulates and studies a general continuous-time behavioral portfolio selection model under Kahneman and Tversky's (cumulative) prospect theory, featuring S-shaped utility (value) functions and probability distortions. Unlike the conventional expected utility maximization model, such a behavioral model could be easily mis-formulated (a.k.a. il

Andrzej Nowojewski, Paul A. Goddard, Stephen J. Blundell

We have developed an analytical model of angle-dependent magnetoresistance oscillations (AMROs) in a quasi-two-dimensional metal in which magnetic breakdown occurs. The model takes account of all the contributions from quasiparticles undergoing both magnetic breakdown and Bragg reflection at each junction and allows extremely efficient simulation of data whi

Céline Robert, S. Durbiano, Eric Blayo, Jacques Verron

This paper presents a reduced-order approach for four-dimensional variational data assimilation, based on a prior EO F analysis of a model trajectory. This method implies two main advantages: a natural model-based definition of a mul tivariate background error covariance matrix $\textbf{B}_r$, and an important decrease of the computational burden o f the met

Simon Rosenfeld

The goal of this paper is to outline a scenario of emerging stochasticity in high-dimensional highly nonlinear systems, such as genetic regulatory networks (GRN). We focus attention on the fact that in such systems confluence of all the factors necessary for gene expression is a comparatively rare event, and only massive redundancy makes such events sufficie

Ruben Cordero, Roberto D. Mota

We study stability of a generalized sine-Gordon model with two coupled scalar fields in two dimensions. Topological soliton solutions are found from the first-order equations that solve the equations of motion. The perturbation equations can be cast in terms of a Schrodinger-like operators for fluctuations and their spectra are calculated.

Wolfgang Reichel, Tobias Weth

We consider the $2m$-th order elliptic boundary value problem $Lu=f(x,u)$ on a bounded smooth domain $Ω$ in $R^N$ with Dirichlet boundary conditions. The operator $L$ is a uniformly elliptic operator of order $2m$. We assume that for $s\to \pm\infty$ the nonlinearity $f(x,s)$ behaves like $|s|^q$ multiplied by a continuous and positive function of $x$. Here

V. Peskov, A. Zichichi

A new flame detector, three orders of magnitude more powerful than the existing ones, is presented. This detector needs to be mass-produced for its use in order to be incorporated in an early forest fire detection system. A project able to implement its use to overcome the forest fire emergency is described.

P. M. Ferreira, R. B. Guedes, R. Santos

We explore the possibility of detecting lepton flavour violation, now a well established experimental fact, at the International Linear Collider. Using a model independent approach we conclude that, given all experimental constraints available, there is still room to detect lepton flavour violation at the ILC.

A. Budzanowski, D. Filges, F. Goldenbaum, A. Heczko

Energy and angular dependence of double differential cross sections d$^2σ$/d$Ω$dE was measured for reactions induced by 2.5 GeV protons on Au target with isotopic identification of light products (H, He, Li, Be, and B) and with elemental identification of heavier intermediate mass fragments (C, N, O, F, Ne, Na, Mg, and Al). It was found that two different re

Céline Robert, Eric Blayo, Jacques Verron

This study demonstrates how the incremental 4D-Var data assimilation method can be applied efficiently preconditione d in an application to an oceanographic problem. The approach consists in performing a few iterations of the reduced-order 4D-Var prior to the incremental 4D-Var in the full space in order to achieve faster convergence. An application performe

L. Giuzzi, A. Sonnino

The main goal of coding theory is to devise efficient systems to exploit the full capacity of a communication channel, thus achieving an arbitrarily small error probability. Low Density Parity Check (LDPC) codes are a family of block codes--characterised by admitting a sparse parity check matrix--with good correction capabilities. In the present paper the or

Nicolas Vuillerme, Nicolas Pinsault, Olivier Chenu, Matthieu Boisgontier

The purpose of the present study was to determine the effects of a plantar pressure-based, tongue-placed tactile biofeedback on postural control mechanisms during quiet standing. To this aim, sixteen young healthy adults were asked to stand as immobile as possible with their eyes closed in two conditions of No-biofeedback and Biofeedback. Centre of foot pres

Carsten van de Bruck, Ki-Young Choi, Lisa M. H. Hall

We provide a detailed analysis of the dynamics of moduli fields in the KKLT scenario coupled to a Polonyi field, which plays the role of a hidden matter sector field. It was previously shown that such matter fields can uplift AdS vacua to Minkowski or de Sitter vacua. Additionally, we take a background fluid into account (which can be either matter or radiat

Céline Robert, Eric Blayo, Jacques Verron

This paper presents a comparison of two reduced-order, sequential and variational data assimilation methods: the SEEK filter and the R-4D-Var. A hybridization of the two, combining the variational framework and the sequential evolution of covariance matrices, is also preliminarily investigated and assessed in the same experimental conditions. The comparison

Hendrik Bartko

The MAGIC telescope with its 17m diameter mirror is today the largest operating single-dish Imaging Air Cherenkov Telescope (IACT). It is located on the Canary Island La Palma, at an altitude of 2200m above sea level, as part of the Roque de los Muchachos European Northern Observatory. The MAGIC telescope detects celestial very high energy gamma-radiation in

Michael Hinczewski, A. Nihat Berker

The recently developed tensor renormalization-group (TRG) method provides a highly precise technique for deriving thermodynamic and critical properties of lattice Hamiltonians. The TRG is a local coarse-graining transformation, with the elements of the tensor at each lattice site playing the part of the interactions that undergo the renormalization-group flo

Andrei Khrennikov, Emmanuel Haven

Probability interference is a fundamental characteristic of quantum mechanics. In this paper we attempt to show with the help of some examples, where this fundamental trait of quantum physics can be found back in a social science environment. In order to support our thesis that interference can possibly be found back in many other macro-scopic areas, we proc

C. Deninger

We point out analogies between (a) the explicit formulas in analytic number theory and transversal index theory, (b) Lichtenbaum's recent conjectures on special values of Hasse-Weil zeta functions and a formula for special values of Ruelle zeta functions, (c) work of Cramer on the zeroes of the Riemann zeta function and a result of Chazarain on the trace

P. Marziani, J. W. Sulentic, D. Dultzin

The last decade saw long-awaited improvements in our understanding of active galactic nuclei (AGN) spectral properties. This contribution reviews some important observational results obtained from optical and UV data as well as constraints on physical parameters that control the structure and dynamics of the Broad Line Region.

Ignatios Antoniadis, Alok Kumar, Binata Panda

We construct a minimal example of a supersymmetric grand unified model in a toroidal compactification of type I string theory with magnetized D9-branes. All geometric moduli are stabilized in terms of the background internal magnetic fluxes which are of "oblique" type (mutually non-commuting). The gauge symmetry is just SU(5) and the gauge non-single

Michal Stukow

Let T(N) be the subgroup of the mapping class group of a nonorientable surface N (possibly with punctures and/or boundary components) generated by twists about two-sided circles. We obtain a simple generating set for T(N). As an application we compute the first homology group (abelianization) of T(N).

A. Sperl, J. Kroeger, N. Neel, H. Jensen

Size-selected silver clusters on Ag(111) were fabricated with the tip of a scanning tunneling microscope. Unoccupied electron resonances give rise to image contrast and spectral features which shift toward the Fermi level with increasing cluster size. Linear assemblies exhibit higher resonance energies than equally sized compact assemblies. Density functiona

Ugo Moschella, Richard Schaeffer

In this paper we set up a general formalism to deal with quantum theories on a Lobatchevski space, i.e. a spatial manifold that is homogeneous, isotropic and has negative curvature. The heart of our approach is the construction of a suitable basis of plane waves which are eigenfunctions of the Laplace-Beltrami operator relative to the geometry of the curved

Stefan Hougardy, Frank H. Lutz, Mariano Zelke

We give explicit realizations with small integer coordinates for all triangulated tori with up to 12 vertices. In particular, we provide coordinate-minimal realizations in general position for all triangulations of the torus with 7, 8, 9, and 10 vertices. For the unique 7-vertex triangulation of the torus we show that all corresponding 72 oriented matroids a

Domenico Sapone, Luca Amendola

The growth factor of linear fluctuations is probably one of the least known quantity in observational cosmology. Here we discuss the constraints that baryon oscillations in galaxy power spectra from future surveys can put on a conveniently parametrized growth factor. We find that spectroscopic surveys of $5000 deg^2$ extending to $z \approx 3$ could estimate

Nachi Gupta, Raphael Hauser

Both constrained and unconstrained optimization problems regularly appear in recursive tracking problems engineers currently address -- however, constraints are rarely exploited for these applications. We define the Kalman Filter and discuss two different approaches to incorporating constraints. Each of these approaches are first applied to equality constrai

Cevdet Tezcand, Ramazan Sever

PT-symmetric solutions of Schrodinger equation are obtained for the Scarf and generalized harmonic oscillator potentials with the position-dependent mass. A general point canonical transformation is applied by using a free parameter. Three different forms of mass distributions are used. A set of the energy eigenvalues of the bound states and corresponding wa

D. Sugny, C. Kontz, M. Ndong, G. Dive

We present a complete analysis of the laser control of a model molecular system using both optimal control theory and adiabatic techniques. This molecule has a particular potential energy surface with a bifurcating region connecting three potential wells which allows a variety of processes such as isomerization, tunnelling or implementation of quantum gates

Ilya Yanov, Juan Jose Palacios, Glake Hill

An ab initio Green's function study of the electron transport properties of the selected metal-porphyrin complexes has been performed. Transmission spectra and current-voltage dependence have been calculated for the porphyrin molecule located between gold electrodes in the presence of interaction with metal atoms, which are most common in biochemistry (F

Mohamed Assad Abdel-Raouf

The theory of four-body systems is revisited. It is illustrated that the theory provides a rigorous proof for the formation of ground state (unexcited) biexcitons in molecular crystals. The generalization of the theory predicts the possible existence of excited biexcitons in nature. In order to test the validity of the extended theory on computational level,

R. Ledesma-Aguilar, I. Pagonabarraga, A. Hernandez-Machado

We perform a three-dimensional study of steady state viscous fingers that develop in linear channels. By means of a three-dimensional Lattice-Boltzmann scheme that mimics the full macroscopic equations of motion of the fluid momentum and order parameter, we study the effect of the thickness of the channel in two cases. First, for total displacement of the fl

J. Ambjorn, R. Loll, W. Westra, S. Zohren

The formalism of causal dynamical triangulations (CDT) provides us with a non-perturbatively defined model of quantum gravity, where the sum over histories includes only causal space-time histories. Path integrals of CDT and their continuum limits have been studied in two, three and four dimensions. Here we investigate a generalization of the two-dimensional

R. Ledesma-Aguilar, A. Hernandez-Machado, I. Pagonabarraga

We study the forced displacement of a fluid-fluid interface in a three-dimensional channel formed by two parallel solid plates. Using a Lattice-Boltzmann method, we study situations in which a slip velocity arises from diffusion effects near the contact line. The difference between the slip and channel velocities determines whether the interface advances as

Ilya Yanov, Glake Hill

Although a vast amount of experimental information is available on the elongation, compression, and folding of proteins in biochemical processes, very little is known about the real structure and molecular dynamics of DNA at an atomic level. Since this area of work is relatively new, this paper reports the results of computer simulation of elongation and com

Ulf R. Pedersen, Günther H. Peters, Thomas B. Schrøder, Jeppe C. Dyre

Constant-pressure molecular-dynamics simulations of phospholipid membranes in the fluid phase reveal strong correlations between equilibrium fluctuations of volume and energy on the nanosecond time-scale. The existence of strong volume-energy correlations was previously deduced indirectly by Heimburg from experiments focusing on the phase transition between

T. Hyvonen, J. K. Kotilainen, R. Falomo, E. Orndahl

We present B-band imaging of 18 low redshift (z<0.3) BL Lac objects for which their host galaxies were previously resolved in the R-band and the near-infrared H-band. For a subset of the objects, also U- and V-band imaging is presented. These data are used to investigate the blue-red-near-infrared colours and the colour gradients of the host galaxies of BL L

T. L. Schmidt, A. Komnik, A. O. Gogolin

We analyze the spin-resolved full counting statistics of electron transfer through an ultrasmall quantum dot coupled to metallic electrodes. Modelling the setup by the Anderson Hamiltonian, we explicitly take into account the onsite Coulomb repulsion $U$. We calculate the cumulant generating function for the probability to transfer a certain number of electr

G. Pedaletti, S. Wagner, W. Benbow

Jets of Active Galactic Nuclei (AGN) are established emitters of very high energy (VHE; >100 GeV) gamma-rays. VHE radiation is also expected to be emitted from the vicinity of super-massive black holes (SMBH), irrespective of their activity state. Accreting SMBH rotate and generate a dipolar magnetic field. In the magnetosphere of the spinning black hole, ac

Abdelhakim Aknouche Hacène Belbachir Fayçal Hamdi

An analytically simple and tractable formula for the start-up autocovariances of periodic ARMA (PARMA) models is provided.

A. Etheridge, P. Pfaffelhuber, A. Wakolbinger

The evolutionary force of recombination is lacking in asexually reproducing populations. As a consequence, the population can suffer an irreversible accumulation of deleterious mutations, a phenomenon known as Muller&#39;s ratchet. We formulate discrete and continuous time versions of Muller&#39;s ratchet. Inspired by Haigh&#39;s (1978) analysis of a dynamic

Y. Zhou

We investigate the influence on the density of states and the density of spin polarization for a two-dimensional hole gas with Rashba spin-orbit coupling under intense terahertz laser fields. Via Floquet theorem, we solve the time-dependent Schrödinger equation and calculate these densities. It is shown that a terahertz magnetic moment can be induced for low

M. Vepsalainen

This paper is a slightly modified version of the introductory part of a doctoral dissertation also containing the articles hep-ph/0311268, hep-ph/0510375, hep-ph/0512177 and hep-ph/0701250. The thesis discusses effective field theory methods, in particular dimensional reduction, in the context of finite temperature field theory. We first briefly review the f

Stefan Adams, Wolfgang König

We review probabilistic approaches to the Gross-Pitaevskii theory describing interacting dilute systems of particles. The main achievement are large deviations principles for the mean occupation measure of a large system of interacting Brownian motions in a trapping potential. The corresponding rate functions are given as variational problems whose solution

E. I. Vorobyov, Ch. Theis

We present a numerical study of the properties of the stellar velocity distribution in stellar discs which have developed a saturated, two-armed spiral structure. We follow the growth of the spiral structure deeply into the non-linear regime by solving the Boltzmann moment equations up to second order. By adopting the thin-disc approximation, we restrict our

Arnaud Courcelle, John Rowlands

In the theory of resonant scattering, the double differential cross section involves the computation of a multifold integral of a 4-point correlation function, which generalizes the traditional 2-point correlation function of Van-Hove for potential scattering. In the case of a neutron-crystal interaction, the numerical computation of these multifold integral

Mihalis Dafermos, Igor Rodnianski

We consider solutions to the linear wave equation $\Box_gϕ=0$ on a non-extremal maximally extended Schwarzschild-de Sitter spacetime arising from arbitrary smooth initial data prescribed on an arbitrary Cauchy hypersurface. (In particular, no symmetry is assumed on initial data, and the support of the solutions may contain the sphere of bifurcation of the bl

D. Sugny, P. Mardesic, M. Pelletier, A. Jebrane

Fractional Hamiltonian Monodromy is a generalization of the notion of Hamiltonian Monodromy, recently introduced by N. N. Nekhoroshev, D. A. Sadovskii and B. I. Zhilinskii for energy-momentum maps whose image has a particular type of non-isolated singularities. In this paper, we analyze the notion of Fractional Hamiltonian Monodromy in terms of the Gauss-Man

Herbert Koch, Hart F. Smith, Daniel Tataru

We establish asymptotic bounds on the L^p norms of spectrally localized functions in the case of two-dimensional Dirichlet forms with coefficients of Lipschitz regularity. These bounds are new for the range p>6. A key step in the proof is bounding the rate at which energy spreads for solutions to hyperbolic equations with Lipschitz coefficients.

L. Deak, L. Bottyan, D. L. Nagy, H. Spiering

Theoretical description of off-specular grazing-incidence nuclear resonant scattering of synchrotron radiation (Synchrotron Mössbauer Reflectometry, SMR) is presented. The recently developed SMR, similarly to polarized neutron reflectometry (PNR), is an analytical tool for the determination of isotopic and magnetic structure of thin films and multilayers. It