November 2008 arXiv papers — page 3

H. Lange, P. E. Newstead

For smooth projective curves the Clifford index is an important invariant which provides a bound for the dimension of the space of sections of a line bundle. This is the first step in distinguishing curves of the same genus. In this paper we generalise this to introduce Clifford indices for semistable vector bundles on curves. We study these invariants, givi

V. P. Maslov, V. E. Nazaikinskii

This paper has been withdrawn by the authors, because it has been made obsolete by the detailed expositions in our papers in arXiv:0812.4885 (the mathematics part) and arXiv:0812.4737 (the economics part).

Timothy G Clemson, Andrew R Liddle

We use a dynamical systems approach to study thawing quintessence models, using a multi-parameter extension of the exponential potential which can approximate the form of typical thawing potentials. We impose observational constraints using a compilation of current data, and forecast the tightening of constraints expected from future dark energy surveys, as

T. Kallinger, W. W. Weiss, C. Barban, F. Baudin

Context. Observations and analysis of solar-type oscillations in red-giant stars is an emerging aspect of asteroseismic analysis with a number of open questions yet to be explored. Although stochastic oscillations have previously been detected in red giants from both radial velocity and photometric measurements, those data were either too short or had sampli

Sheng-Lan Ko, Jen-Chi Lee, Yi Yang

Based on a summation algorithm for Stirling number identity developed recently, we discover that the ratios calculated previously among high energy string scattering amplitudes in the Gross regime (GR) can be extracted from the Kummer function of the second kind. This function naturally shows up in the leading order of high energy string scattering amplitude

Yoshiharu Kawamura

We construct grand unified models on an orbifold based on unphysical grand unification. The reduction to the standard model or its supersymmetric one is carried out using a variant of Parisi-Sourlas mechanism and nontrivial $Z_2$ parity assignment.

Hiroyuki Okagawa, Shozo Uehara, Satoshi Yamada

We consider a wrapped supermembrane around non-trivial two cycles of a 2-torus. We examine the double dimensional reduction and the T-dual transformation to deduce Green-Schwarz type IIB superstring action for (p,q)-strings directly from the wrapped supermembrane on the 2-torus. The resulting action has the couplings with both the NSNS- and the RR-background

M. Musakhanov

In the framework of the instanton vacuum model we make expansion over the current mass $m$ and number of colors $N_c$ and evaluate ${\cal O}(1/N_c, m, m/N_c, m \ln m/N_c)$-corrections to the dynamical quark mass $M$, the quark condensate $<\bar qq>$, the pion mass $M_π$ and decay constant $F_π$. We found the SU(2) $χ$PT low-energy constants $\bar l_3, \bar l

Yemon Choi, Matthew J. Heath

We characterize those derivations from the convolution algebra $\ell^1({\mathbb Z}_+)$ to its dual which are weakly compact. In particular, we provide examples which are weakly compact but not compact. The characterization is combinatorial, in terms of &#34;translation-finite&#34; subsets of ${\mathbb Z}_+$, and we investigate how this notion relates to othe

Dongho Chae

We study Liouville type of theorems for the Navier-Stokes and the Euler equations on $\Bbb R^N$, $N\geq 2$. Specifically, we prove that if a weak solution $(v,p)$ satisfies $|v|^2 +|p| \in L^1 (0,T; L^1(\Bbb R^N, w_1(x)dx))$ and $\int_{\Bbb R^N} p(x,t)w_2 (x)dx \geq0$ for some weight functions $w_1(x)$ and $w_2 (x)$, then the solution is trivial, namely $v=0

Tommaso de Fernex, Mircea Mustata

Shokurov&#39;s ACC Conjecture says that the set of all log canonical thresholds on varieties of bounded dimension satisfies the Ascending Chain Condition. This conjecture was proved for log canonical thresholds on smooth varieties in [EM1]. Here we use this result and inversion of adjunction to establish the conjecture for locally complete intersection varie

Hiroki Sumi

We investigate the dynamics of polynomial semigroups (semigroups generated by a family of polynomial maps on the Riemann sphere) and the random dynamics of polynomials on the Riemann sphere. Combining the dynamics of semigroups and the fiberwise (random) dynamics, we give a classification of polynomial semigroups $G$ such that $G$ is generated by a compact f

A. Tsukazaki, A. Ohtomo, M. Kawasaki, S. Akasaka

We report measurements of the spin susceptibility and the electron effective mass for two-dimensional electrons confined at the interfaces of MgxZn1-xO/ZnO single heterostructures (x = 0.05, 0.08, and 0.11), grown by molecular-beam epitaxy on (0001) ZnO substrates. By tuning the built-in polarization through control of the barrier composition, the electron d

Alfredo Vega, Ivan Schmidt

We present an holographical soft wall model which is able to reproduce not only Regge spectra for hadrons with arbitrary integer spin, but also with spin 1/2 and 3/2, and with an arbitrary number of constituents. The model includes the anomalous dimension of operators than create hadrons, together with a dilaton, whose form is suggested by Einstein equations

Tetsuro Konishi, Tatsuo Yanagita

We propose a planar chain system, which is a simple mechanical system with a constraint. It is composed of $N$ masses connected by $N-1$ light links. It can be considered as a model of a chain system, e.g., a polymer, in which each bond is replaced by a rigid link. The long time average of the kinetic energies of the masses in this model is numerically compu

Amir Haji-Akbari, Robert M. Ziff

A general method is proposed for predicting the asymptotic percolation threshold of networks with bottlenecks, in the limit that the sub-net mesh size goes to zero. The validity of this method is tested for bond percolation on filled checkerboard and &#34;stack-of-triangle&#34; lattices. Thresholds for the checkerboard lattices of different mesh sizes are es

Jun Jing, Zhi-Guo Lu, Zbigniew Ficek

It is well established that an entanglement encoded in the Bell states of a two-qubit system with correlated spins exhibits completely different evolution properties than that encoded in states with the anti-correlated spins. A complete and abrupt loss of the entanglement, called the entanglement sudden death, can be found to occur for the spin correlated st

Serge F. Timashev, Yuriy S. Polyakov

This review presents the fundamentals of Flicker-Noise Spectroscopy (FNS), a general phenomenological methodology in which the dynamics and structure of complex systems, characterized by nonlinear interactions, dissipation, and inertia, are analyzed by extracting information from various signals with stochastically varying components generated by the systems

Surajit Saha, Surjeet Singh, B. Dkhil, S. Dhar

We present here temperature-dependent Raman, x-ray diffraction and specific heat studies between room temperature and 12 K on single crystals of spin-ice pyrochlore compound $Dy_2Ti_2O_7$ and its non-magnetic analogue $Lu_2Ti_2O_7$. Raman data show a &#34;new&#34; band not predicted by factor group analysis of Raman-active modes for the pyrochlore structure

Stefan Legewie, Dennis Dienst, Annegret Wilde, Hanspeter Herzel

Non-coding RNAs are crucial regulators of gene expression in prokaryotes and eukaryotes, but it remains poorly understood how they affect the dynamics of transcriptional networks. We analyzed the temporal characteristics of the cyanobacterial iron stress response by mathematical modeling and quantitative experimental analyses, and focused on the role of a re

D. Belitz, T. R. Kirkpatrick

We prove that a diagrammatic evaluation of the Kubo formula for the electronic transport conductivity due the exchange of bosonic excitations, in the usual conserving ladder approximation, yields a result consistent with the Boltzmann equation. In particular, we show that an uncontrolled approximation that has been used to solve the integral equation for the

Hans Feichtinger, Chunyan Huang, Baoxiang Wang

In this paper, we consider the trace theorem for modulation spaces, alpha modulation spaces and Besov spaces. For the modulation space, we obtain the sharp results.

Ali Godjali

Let $\fld$ denote a field and $V$ denote a nonzero finite-dimensional vector space over $\fld$. We consider an ordered pair of linear transformations $A: V \to V$ and $A^*: V \to V$ that satisfy (i)--(iii) below. Each of $A, A^*$ is diagonalizable on $V$. There exists an ordering $\lbrace V_i \rbrace_{i=0}^d$ of the eigenspaces of $A$ such that A^* V_i \subs

Ramesh Narayan, Pawan Kumar

A popular paradigm to explain the rapid temporal variability observed in gamma-ray burst (GRB) lightcurves is the internal shock model. We propose an alternative model in which the radiating fluid in the GRB shell is relativistically turbulent with a typical eddy Lorentz factor $γ_t$. In this model, all pulses in the gamma-ray lightcurve are produced at roug

I. Klich, L. S. Levitov

Particle number conservation in fermionic systems restricts the allowed local operations on bi-partite systems. We show how this restriction is related to measurement entropy of particle fluctuations and compute it for several regimes of practical relevance. The accessible entanglement entropy restricted by particle number conservation is equal, to leading o

R. Soto, G. Martínez, M. N. Baibich, J. M. Florez

It is known that the spin-chain compound Ca3Co2O6 exhibits very interesting plateaus in the magnetization as a function of the magnetic field at low temperatures. The origin of them is still controversial. In this paper we study the thermal behavior of this compound with a single-flip Monte Carlo simulation on a triangular lattice and demonstrate the decisiv

N. K. Kuzmenko, V. M. Mikhajlov

Temperature variations of the heat capacity (C) are studied in a low temperature regime for 2D-, and 3D-systems with N~100-10000 treated as a canonical ensemble of N-noninteracting fermions. The analysis of C is performed by introducing function q, the spectral distribution of C, that gives the contribution of each single-particle state to C. This function h

M. Maheswaran, J. P. Cassinelli

We develop equations and obtain solutions for the structure and evolution of a protodisc region that is initially formed with no radial motion and super-Keplerian rotation speed when wind material from a hot rotating star is channelled towards its equatorial plane by a dipole-type magnetic field. Its temperature is around $10^7$K because of shock heating and

Jacob J. H. Simmons, John Cardy

Using conformal field theoretic methods we calculate correlation functions of geometric observables in the loop representation of the O(n) model at the critical point. We focus on correlation functions containing twist operators, combining these with anchored loops, boundaries with SLE processes and with double SLE processes. We focus further upon n=0, repre

Klaus Denecke, Jorg Koppitz, Slavcho Shtrakov

For given depth of a we derive a formula for the depth of the image of that term under a given hypersubstitution.

T. J. Christiansen, P. D. Hislop

We prove that the resonance counting functions for Schrödinger operators $H_V = - Δ+ V$ on $L^2 (\R^d)$, for $d \geq 2$ {\it even}, with generic, compactly-supported, real- or complex-valued potentials $V$, have the maximal order of growth $d$ on each sheet $Λ_m$, $m \in \Z \backslash \{0 \}$, of the logarithmic Riemann surface. We obtain this result by cons

C. M. Carloni Calame, S. Moretti, F. Piccinini, D. A. Ross

We compute the full one-loop EW contributions of O(α_S alpha_EM^3) entering the electron-positron into two b-quarks and one gluon cross section at the Z peak and LC energies. We include both factorisable and non-factorisable virtual corrections, photon bremsstrahlung but not the real emission of W^\pm and Z bosons. Their importance for the measurement of alp

Nikolaos Kidonakis

I discuss recent calculations of higher-order corrections to charged Higgs production through various partonic subprocesses. Particular attention is paid to H- production in association with a top quark at the LHC.

Gerónimo Uribe Bravo

We present a further analysis of the fragmentation at heights of the normalized Brownian excursion. Specifically we study a representation for the mass of a tagged fragment in terms of a Doob transformation of the 1/2-stable subordinator and use it to study its jumps; this accounts for a description of how a typical fragment falls apart. These results carry

L. Leger, F. Paletou

The diagnosis of new high-resolution spectropolarimetric observations of solar prominences made in the visible and near-infrared mainly, requires a radiative modelling taking into account for both multi-dimensional geometry and complex atomic models. Hereafter we contribute to the improvement of the diagnosis based on the observation of He I multiplets, by c

Li-Li Yu, M. J. Efaaf, Yan-Yu Ren, Wei-Ning Zhang

Using the technique of quantum transport of the interfering pair we examine the Hanbury-Brown-Twiss (HBT) interferometry signatures for the particle-emitting sources of pions and kaons produced in the heavy ion collisions at GSI-FAIR energies. The evolution of the sources is described by relativistic hydrodynamics with the system equation of state of the fir

T. T. Koskinen, A. D. Aylward, S. Miller

HD17156b is a newly-found transiting extrasolar giant planet (EGP) that orbits its G-type host star in a highly eccentric orbit (e~0.67) with an orbital semi-major axis of 0.16 AU. Its period, 21.2 Earth days, is the longest among the known transiting planets. The atmosphere of the planet undergoes a 27-fold variation in stellar irradiation during each orbit

Horacio Dottori, Ruben J. Diaz, Damian Mast

We present Gemini optical imaging and spectroscopy of the radio source J 133658.3-295105. This source has been suggested to be the core of an FR II radio source with two detected lobes. J 133658.3-295105 and its lobes are aligned with the optical nucleus of M 83 and with three other radio sources at the M 83 bulge outer region. These radio sources are neithe

Xavier Calbet, Ricardo Lopez-Ruiz

In this work, it is suggested that the extremum complexity distribution of a high dimensional dynamical system can be interpreted as a piecewise uniform distribution in the phase space of its accessible states. When these distributions are expressed as one--particle distribution functions, this leads to piecewise exponential functions. It seems plausible to

Guillermo Bosch, Elena Terlevich, Roberto Terlevich

If binaries are common among massive stars, it will have important consequences for the derivation of fundamental properties like the cluster age, IMF and dynamical mass. Making use of the multiplexing facilities of Gemini Multi Object Spectrograph (GMOS) we were able to investigate the presence of binary stars within the ionising cluster of 30 Doradus. From

Christian Spiering

The year 2008 has witnessed remarkable steps in developing high energy neutrino telescopes. IceCube at the South Pole has been deployed with 40 of its planned 80 strings and reached half a cubic kilometer instrumented volume, in the Mediterranean Sea the &#34;first-stage&#34; neutrino telescope ANTARES has been completed and takes data with 12 strings. The n

C. Nair, M. Erhard, A. R. Junghans, D. Bemmerer

The 197Au(gamma,n) reaction is used as an activation standard for photodisintegration studies on astrophysically relevant nuclei. At the bremsstrahlung facility of the superconducting electron accelerator ELBE (Electron Linear accelerator of high Brilliance and low Emittance) of Forschungszentrum Dresden-Rossendorf, photoactivation measurements on 197Au have

N. Auerbach

Corrections to the superallowed beta decay matrix elements are evaluated in perturbation theory using the notion of the isovector monopole resonance. The calculation avoids the separation into different contributions and thus presents a consistent, systematic and more transparent approach. Explicit expressions for the Coulomb correction as a function of mass

J. Kvasil, P. Vesely, V. O. Nesterenko, W. Kleinig

The isovector dipole E1 strength in Mo isotopes with A=92,94,96,98,100 is analyzed within the self-consistent separable random-phase approximation (SRPA) model with Skyrme forces SkT6, SkM*, SLy6, and SkI3. The special attention is paid to the low-energy region near the particle thresholds (4-12 MeV), which is important for understanding of astrophysical pro

I. M. Sokolov, E. Heinsalu, P. Hanggi, I. Goychuk

Subdiffusive transport in tilted washboard potentials is studied within the fractional Fokker-Planck equation approach, using the associated continuous time random walk (CTRW) framework. The scaled subvelocity is shown to obey a universal law, assuming the form of a stationary Levy-stable distribution. The latter is defined by the index of subdiffusion alpha

Gautami Bhowmik, Immanuel Halupczok, Jan-Christoph Schlage-Puchta

Let n be an integer, and consider finite sequences of elements of the group Z/nZ x Z/nZ. Such a sequence is called zero-sum free, if no subsequence has sum zero. It is known that the maximal length of such a zero-sum free sequence is 2n-2, and Gao and Geroldinger conjectured that every zero-sum free sequence of this length contains an element with multiplici

Nimesh A. Patel, Ken H. Young, Sandra Brünken, Karl M. Menten

Using the Submillimeter Array we have detected the J=3-2 and 2-1 rotational transitions from within the first vibrationally excited state of CO toward the extreme carbon star IRC+10216 (CW Leo). The emission remains spatially unresolved with an angular resolution of ~2&#34; and, given that the lines originate from energy levels that are ~3100 K above the gro

David Vignolles, Alain Audouard, Rustem B. Lyubovskii, Marc Nardone

Pressure dependence of the Shubnikov-de Haas (SdH) oscillations spectra of the quasi-two di- mensional organic metal (ET)8[Hg4Cl12(C6H5Br)]2 have been studied up to 1.1 GPa in pulsed magnetic fields of up to 54 T. According to band structure calculations, its Fermi surface can be regarded as a network of compensated orbits. The SdH spectra exhibit many Fouri

E. M. Ganapolskii, Z. E. Eremenko, Yu. V. Tarasov

The influence of random surface inhomogeneities on spectral properties of open microresonators is studied both theoretically and experimentally. To solve the equations governing the dynamics of electromagnetic fields the method of eigen-mode separation is applied previously developed with reference to inhomogeneous systems subject to arbitrary external stati

Daniel Kanaan, Philippe Wenger, Damien Chablat

The paper derives the inverse and the forward kinematic equations of a serial - parallel 5-axis machine tool: the VERNE machine. This machine is composed of a three-degree-of-freedom (DOF) parallel module and a two-DOF serial tilting table. The parallel module consists of a moving platform that is connected to a fixed base by three non-identical legs. These

Yongsheng Huang, Yuanjie Bi, Xiaojiao Duan, Naiyan Wang

A two-dimension self-similar solution is proposed for a plasma expansion with anisotropic pressure. With the solution, it depends on the relationship between the ratio of the longitudinal and the transverse temperature of the plasma, $κ^2$ and the electron-ion mass ratio, $μ$, that the plasma front is composed by a part of hyperbolic (or a plane) and a small

C. Groh, N. Aksel, I. Rehberg, C. Kruelle

The dependence of the barchan dune dynamics on the size of the grains involved is investigated experimentally. Downsized barchan dune slices are observed in a narrow water flow tube. The relaxation time from an initial symmetric triangular heap towards an asymmetric shape attractor increases with dune mass and decreases with grain size. The dune velocity inc

James J. Uren

In this note we give a brief review of the construction of a toric variety $\mathcal{V}$ coming from a genus $g \geq 2$ Riemann surface $Σ^g$ equipped with a trinion, or pair of pants, decomposition. This was outlined by J. Hurtubise and L. C. Jeffrey in \cite{JH1}. In \cite{T1} A. Tyurin used this construction on a certain collection of trinion decomposed s

C. Plainaki, A. Milillo, S. Orsini, A. Mura

The ion-sputtering (IS) process is active in many planetary environments in the Solar System where plasma precipitates directly on the surface (for instance, Mercury, Moon, Europa). In particular, solar-wind sputtering is one of the most important agents for the surface erosion of a Near-Earth Object (NEO), acting together with other surface release processe

Michel Journée, Yurii Nesterov, Peter Richtárik, Rodolphe Sepulchre

In this paper we develop a new approach to sparse principal component analysis (sparse PCA). We propose two single-unit and two block optimization formulations of the sparse PCA problem, aimed at extracting a single sparse dominant principal component of a data matrix, or more components at once, respectively. While the initial formulations involve nonconvex

S. Orsini, A. M. Di Lellis, A. Milillo, E. De Angelis

The neutral sensor ELENA (Emitted Low-Energy Neutral Atoms) for the ESA cornerstone BepiColombo mission to Mercury (in the SERENA instrument package) is a new kind of low energetic neutral atoms instrument, mostly devoted to sputtering emission from planetary surfaces, from E ~20 eV up to E~5 keV, within 1-D (2x76 deg). ELENA is a Time-of-Flight (TOF) system

Adel Bouhoula, Florent Jacquemard

We propose a procedure for automated implicit inductive theorem proving for equational specifications made of rewrite rules with conditions and constraints. The constraints are interpreted over constructor terms (representing data values), and may express syntactic equality, disequality, ordering and also membership in a fixed tree language. Constrained equa

Xavier Illa, Josep Maria Huguet, Eduard Vives

We perform a numerical study of the three-dimensional Random Field Ising Model at T=0. We compare work distributions along metastable trajectories obtained with the single-spin flip dynamics with the distribution of the internal energy change along equilibrium trajectories. The goal is to investigate the possibility of extending the Crooks fluctuation theore

Carl Bracken, Zhengbang Zha

It is well known that a quadratic function defined on a finite field of odd degree is almost bent (AB) if and only if it is almost perfect nonlinear (APN). For the even degree case there is no apparent relationship between the values in the Fourier spectrum of a function and the APN property. In this article we compute the Fourier spectrum of the new quadran

Roxana Teodorescu, Daniel Racoceanu, Wee-Kheng Leow, Vladimir Cretu

One important challenge in modern Content-Based Medical Image Retrieval (CBMIR) approaches is represented by the semantic gap, related to the complexity of the medical knowledge. Among the methods that are able to close this gap in CBMIR, the use of medical thesauri/ontologies has interesting perspectives due to the possibility of accessing on-line updated r

Amandine Aftalion, Xavier Blanc, Nicolas Lerner

We investigate the effect of the anisotropy of a harmonic trap on the behaviour of a fast rotating Bose-Einstein condensate. This is done in the framework of the 2D Gross-Pitaevskii equation and requires a symplectic reduction of the quadratic form defining the energy. This reduction allows us to simplify the energy on a Bargmann space and study the asymptot

Frédéric Chapoton, Alessandra Frabetti

This paper is a brief mathematical excursion which starts from quantum electrodynamics and leads to the Moebius function of the Tamari lattice of planar binary trees, within the framework of groups of tree-expanded series. First we recall Brouder&#39;s expansion of the photon and the electron Green&#39;s functions on planar binary trees, before and after the

R. Werner, C. Raisch, V. Leca, V. Ion

Cerium-doped manganite thin films were grown epitaxially by pulsed laser deposition at $720 ^\circ$C and oxygen pressure $p_{O_2}=1-25 $Pa and were subjected to different annealing steps. According to x-ray diffraction (XRD) data, the formation of CeO$_2$ as a secondary phase could be avoided for $p_{O_2}\ge 8 $Pa. However, transmission electron microscopy s

S. A. Hussain, P. K. Paul, D. Bhattacharjee

This paper reports the pi-A isotherms and spectroscopic characteristics of mixed Langmuir and Langmuir-Blodgett (LB) films of non-amphiphilic carbazole (CA) molecules mixed with polymethyl methacrylate (PMMA) and stearic acid (SA). pi-A isotherm studies of mixed monolayer and as well as also the collapse pressure study of isotherms definitely conclude that C

C. Sasaki, K. Redlich

We analyze the transport properties of relativistic fluid composed of constituent quarks at finite temperature and density. We focus on the shear and bulk viscosities and study their behavior near chiral phase transition. We model the constituent quark interactions through the Nambu--Jona Lasinio Lagrangian. The transport coefficients are calculated within k

J. Rodriguez, J. A. Tomsick, S. Chaty

(abridged) We analysed data from observations of 17 INTEGRAL sources made with the Swift satellite. We refine the position of the hard X-ray sources to an accuracy of a few arcsec. We then browsed the online catalogs (e.g., NED, SIMBAD, 2MASS, 2MASX, USNO) to search for counterparts at other wavelengths. We also made use of the X-ray spectral parameters to t

Shubhrangshu Ghosh, Banibrata Mukhopadhyay

We provide a 2.5-dimensional solution to a complete set of viscous hydrodynamical equations describing accretion-induced outflow and then plausible jet around black holes/compact objects. We prescribe a self-consistent advective disk-outflow coupling model, which explicitly includes the information of vertical flux. Inter-connecting dynamics of inflow-outflo

Birgit Richter

We interpret divided power structures on the homotopy groups of simplicial commutative rings as having a counterpart in divided power structures on chain complexes coming from a non-standard symmetric monoidal structure.

Stéphane Pateux, Gaëtan Le Guelvouit, Christine Guillemot

The theoretical foundations of data hiding have been revealed by formulating the problem as message communication over a noisy channel. We revisit the problem in light of a more general characterization of the watermark channel and of weighted distortion measures. Considering spread spectrum based information hiding, we release the usual assumption of an i.i

N. A. Gromov

The limiting case of the bosonic part of the standard Electroweak Model, which correspond to the contracted gauge group $ SU(2;j)\times U(1)$ is discussed. The Higgs boson, Z-boson and electromagnetic fields become an external ones with respect to the W-bosons fields. The W-bosons fields do not effect on these external fields. The masses of the all particles

Gaëtan Le Guelvouit

This paper deals with public-key steganography in the presence of a passive warden. The aim is to hide secret messages within cover-documents without making the warden suspicious, and without any preliminar secret key sharing. Whereas a practical attempt has been already done to provide a solution to this problem, it suffers of poor flexibility (since embedd

Sofiane Braci, Claude Delpha, Rémy Boyer, Gaëtan Le Guelvouit

Several authors have studied stego-systems based on Costa scheme, but just a few ones gave both theoretical and experimental justifications of these schemes performance in an active warden context. We provide in this paper a steganographic and comparative study of three informed stego-systems in active warden context: scalar Costa scheme, trellis-coded quant

S. Kabbaj, A. Mimouni

The t-class semigroup of an integral domain is the semigroup of fractional t-ideals modulo its subsemigroup of nonzero principal ideals with the operation induced by ideal t-multiplication. This paper investigates ring-theoretic properties of a Noetherian domain that reflect reciprocally in the Clifford or Boolean property of its t-class semigroup.

Yoichi Murakami, Shigeo Maruyama

We studied optical absorption of single-walled carbon nanotubes by varying the dielectric environment. For the two different components of the broad UV absorption feature conventionally referred to as the pi-plasmon, we find that the component at 5.0 - 5.3 eV exhibits remarkable spectral changes, based on which we attribute this to a dipolar radial surface p

S. Bouchiba, S. Kabbaj

This paper deals with Bouvier&#39;s conjecture which sustains that finite-dimensional non-Noetherian Krull domains need not be Jaffard

Denis Perrot

We review some facts about bivariant Chern characters in Noncommutative Geometry and anomaly formulas in Quantum Field Theory.

P. Ryan

The single-top production cross section is one third that of the top-pair production cross section at the LHC. During a year of data-taking, assuming an average luminosity of 10^33 cm-2 s-1 and a CMS energy of 14 TeV, the determination of the major contributions to the total single-top cross section should be achievable. Comparisons between the measured cros

Pavle Saksida, Tomaz Prosen

Rigorous lower bound on the time-average of the autocorrelation function of an arbitrary L^1 observable is proven in terms of conserved quantities and ergodic decompositions of the Hamiltonian dynamics. Improvements with respect to the bounds given by Mazur and Suzuki are discussed.

ALEPH Collaboration, CDF Collaboration, D0 Collaboration, DELPHI Collaboration

This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak measurements from other experiments, notably CDF and DØat the Tevatron. Constraints on the input parameters of the Standard Model a

Gaëtan Le Guelvouit, Teddy Furon, François Cayre

The Good is Blondie, a wandering gunman with a strong personal sense of honor. The Bad is Angel Eyes, a sadistic hitman who always hits his mark. The Ugly is Tuco, a Mexican bandit who&#39;s always only looking out for himself. Against the backdrop of the BOWS contest, they search for a watermark in gold buried in three images. Each knows only a portion of t

Gerardo Aquino, Filippo Giraldi

An initial unknown quantum state can be determined with a single measurement apparatus by letting it interact with an auxiliary, "Ancilla", system as proposed by Allahverdyan, Balian and Nieuwenhuizen [Phys. Rev. Lett. 92, 120402 (2004)]. In the case of two qubits, this procedure allows to reconstruct the initial state of the qubit of interest S by measuring

Yang Xing

The classical condition on the existence of uniformly exponentially consistent tests for testing the true density against the complement of its arbitrary neighborhood has been widely adopted in study of asymptotics of Bayesian nonparametric procedures. Because we follow a Bayesian approach, it seems to be more natural to explore alternative and appropriate c

In-Cheol Baek, Young-Je Yun, Mu-Yong Choi

Transport measurements are carried out on dice Josephson-junction arrays with the frustration index $f=1/3$ and 1/2 which possess, within the limit of the $XY$ model, an accidental degeneracy of the ground states as a consequence of the formation of zero-energy domain walls. The measurements demonstrate that both the systems undergo a phase transition to a s

Emad Soroush, Kui Wu, Jian Pei

In many emerging applications, data streams are monitored in a network environment. Due to limited communication bandwidth and other resource constraints, a critical and practical demand is to online compress data streams continuously with quality guarantee. Although many data compression and digital signal processing methods have been developed to reduce da

F. Guinea, B. Horovitz, P. Le Doussal

We analyze elastic deformations of graphene sheets which lead to effective gauge fields acting on the charge carriers. Corrugations in the substrate induce stresses, which, in turn, can give rise to mechanical instabilities and the formation of wrinkles. Similar effects may take place in suspended graphene samples under tension.

S. Igonin, J. van de Leur, G. Manno, V. Trushkov

The Wahlquist-Estabrook prolongation method allows to obtain for some PDEs a Lie algebra that is responsible for Lax pairs and Backlund transformations of certain type. We study the Wahlquist-Estabrook algebra of the n-dimensional generalization of the Landau-Lifshitz equation and construct an epimorphism from this algebra onto an infinite-dimensional quasig

Valerio Faraoni, Changjun Gao, Xuelei Chen, You-Gen Shen

Within a large class of exact solutions of the Einstein equations describing a black hole embedded in a Friedmann universe it is shown that, under certain assumptions, only those with comoving Hawking-Hayward quasi-local mass are generic, in the sense that they are late-time attractors.

Anda Olteanu, Oana Olteanu, Loredana Sorrenti

In this paper we characterize the componentwise lexsegment ideals which are componentwise linear and the lexsegment ideals generated in one degree which are Gotzmann.

Scott J. Kenyon, Benjamin C. Bromley

We describe a coagulation model that leads to the rapid formation of super-Earths and the cores of gas giant planets. Interaction of collision fragments with the gaseous disk is the crucial element of this model. The gas entrains small collision fragments, which rapidly settle to the disk midplane. Protoplanets accrete the fragments and grow to masses of at

A. Hietanen, K. Kajantie, M. Laine, K. Rummukainen

We update Monte Carlo simulations of the three-dimensional SU(3) + adjoint Higgs theory, by extrapolating carefully to the infinite volume and continuum limits, in order to estimate the contribution of the infrared modes to the pressure of hot QCD. The sum of infrared contributions beyond the known 4-loop order turns out to be a smooth function, of a reasona

C. B. Muratov, V. V. Osipov

We propose a design for the magnetic memory cell which allows an efficient storage, recording, and readout of information on the basis of thin film ferromagnetic nanorings. The information bit is represented by the polarity of a stable 360$^\circ$ domain wall introduced into the ring. Switching between the two magnetization states is achieved by the current

D. B. Ion, M. L. Ion, L. Rusu

In this paper it is shown that the key to understanding the ghost imaging mystery are the crossing symmetric photon reactions in the nonlinear media. Then, an intuitive mechanism for the description of the ghost imaging in terms of the quantum mirror (QM) is presented. Moreover, we prove that the ghost imaging laws depend only on the energy-momentum conserva

H. Kouno, Y. Sakai, K. Kashiwa, M. Matsuzaki

Using the Polyakov extended Nambu-Jona-Lasinio (PNJL) model with imaginary chemical potential, the relation between the Roberge-Weiss (RW) phase transition and the extended Z3 symmetry is studied. At low temperature, there is approximate continuous symmetry under the phase transformation of the Polyakov loop with the shift of the imaginary chemical potential

A. M. Bobkov, I. V. Bobkova

We theoretically investigate an opportunity to implement a source of highly spin-polarized ac current on the basis of superconductor/weak ferromagnet/superconductor (SFS) voltage-biased junction in the regime of essential proximity effect and calculate the current flowing through the probe electrode tunnel coupled to the ferromagnetic interlayer region. It i

Marco Pignatari, Falk Herwig, Michael Bennett, Steven Diehl

Many nucleosynthesis and mixing processes of low-mass stars as they evolve from the Main Sequence to the thermal-pulse Asymptotic Giant Branch phase (TP-AGB) are well understood (although of course important physics components, e.g. rotation, magnetic fields, gravity wave mixing, remain poorly known). Nevertheless, in the last years presolar grain measuremen

Patrick Young, Carola I. Ellinger, Francis X. Timmes, David Arnett

We examine observed heavy element abundances in the Cassiopeia A supernova remnant as a constraint on the nature of the Cas A supernova. We compare bulk abundances from 1D and 3D explosion models and spatial distribution of elements in 3D models with those derived from X-ray observations. We also examine the cospatial production of 26Al with other species. W

Raphael Hirschi, Urs Frischknecht, F. -K. Thielemann, Marco Pignatari

The s-process production in massive stars at very low metallicities is expected to be negligible due to the low abundance of the neutron source 22Ne, to primary neutron poisons and decreasing iron seed abundances. However, recent models of massive stars including the effects of rotation show that a strong production of 22Ne is possible in the helium core, as

Falk Herwig, Michael Bennett, Steven Diehl, Christopher L. Fryer

Simulations of nucleosynthesis in astrophysical environments are at the intersection of nuclear physics reaction rate research and astrophysical applications, for example in the area of galactic chemical evolution or near-field cosmology. Unfortunately, at present the available yields for such applications are based on heterogeneous assumptions between the v

Georgios Magkotsios, Francis X. Timmes, Michael Wiescher, Christopher L. Fryer

We investigate the physical conditions where 44Ti and 56Ni are created in core-collapse supernovae. In this preliminary work we use a series of post-processing network calculations with parametrized expansion profiles that are representative of the wide range of temperatures, densities and electron-to-baryon ratios found in 3D supernova simulations. Critical

Gabriel Rockefeller, Christopher L. Fryer, Patrick Young, Michael Bennett

The &#34;collapsar&#34; engine for gamma-ray bursts invokes as its energy source the failure of a normal supernova and the formation of a black hole. Here we present the results of the first three-dimensional simulation of the collapse of a massive star down to a black hole, including the subsequent accretion and explosion. The explosion differs significantl