March 2009 arXiv papers — page 9

Karoly Bezdek, Gyorgy Kiss

The X-ray numbers of some classes of convex bodies are investigated. In particular, we give a proof of the X-ray Conjecture as well as of the Illumination Conjecture for almost smooth convex bodies of any dimension and for convex bodies of constant width of dimensions 3, 4, 5 and 6.

Alexander Croy, Ulf Saalmann

A partial fraction decomposition of the Fermi function resulting in a finite sum over simple poles is proposed. This allows for efficient calculations involving the Fermi function in various contexts of electronic structure or electron transport theories. The proposed decomposition converges in a well-defined region faster than exponential and is thus superi

Emanuel Milman

We survey some classical inequalities due to Maz'ya relating isocapacitary inequalities with their functional and isoperimetric counterparts in a measure-metric space setting, and extend Maz'ya's lower bound for the $q$-capacity ($q>1$) in terms of the 1-capacity (or isoperimetric) profile. We then proceed to describe results by Buser, Bakry, Led

Dmitri Akimov, Alexander Bondar, Alexander Burenkov, Alexei Buzulutskov

Estimation of the signal amplitudes and counting rates for coherent scattering of reactor antineutrino off atomic nuclei in two-phase xenon and argon detectors has been done. A conceptual design of detector based on the existing technologies and experience has been proposed. It is shown that a condensed xenon/argon two-phase detector possesses the necessary

Victor Pardo, Warren E. Pickett

Multilayer VO$_2$/TiO$_2$ nanostructures ($d^1$ - $d^0$ interfaces with no polar discontinuity) are studied with first principles density functional methods including structural relaxation. Quantum confinement of the {\it half metallic} VO$_2$ slab within insulating TiO$_2$ produces an unexpected and unprecendented two-dimensional new state, with a {\it semi

R. E. Mennickent, Z. Kolaczkowski

In this paper we give a brief report of our recent research on Double Periodic Variables (DPVs), including the discovery of DPVs in the Galaxy and some insights on the nature of their long-cycle variability.

Sz. Gy. Re've'sz

The Rolling Ball Theorem asserts that given a convex body K in Euclidean space and having a smooth surface bd(K) with all principal curvatures not exceeding c>0 at all boundary points, K necessarily has the property that to each boundary point there exists a ball B_r of radius r=1/c, fully contained in K and touching bd(K) at the given boundary point from th

J. A. Caballero, J. Lopez-Santiago, E. de Castro, M. Cornide

We used the Aladin Virtual Obsrvatory tool and High Resolution Imager ROSAT archival data to search for X-ray variability in scale of days in 23 young stars in the sigma Orionis cluster and a background galaxy. Five stars displayed unambiguous flares and had probabilities p_var >> 99% of being actual variables. Two of the detected flares were violent and lon

Adrian Constantin, Elena Kartashova

The influence of an underlying current on 3-wave interactions of capillary water waves is studied. The fact that in irrotational flow resonant 3-wave interactions are not possible can be invalidated by the presence of an underlying current of constant non-zero vorticity. We show that: 1) wave trains in flows with constant non-zero vorticity are possible only

Nayantara Bhatnagar, Elitza Maneva

For a tree Markov random field non-reconstruction is said to hold if as the depth of the tree goes to infinity the information that a typical configuration at the leaves gives about the value at the root goes to zero. The distribution of the measure at the root conditioned on a typical boundary can be computed using a distributional recurrence. However the e

J. E. Nelson, R. F. Picken

In the context of (2+1)--dimensional gravity, we use holonomies of constant connections which generate a $q$--deformed representation of the fundamental group to derive signed area phases which relate the quantum matrices assigned to homotopic loops. We use these features to determine a quantum Goldman bracket (commutator) for intersecting loops on surfaces,

R. Burioni, F. Corberi, A. Vezzani

We study the phase-ordering kinetics following a temperature quench of O(N) continuous symmetry models with and 4 on graphs. By means of extensive simulations, we show that the global pattern of scaling behaviours is analogous to the one found on usual lattices. The exponent a for the integrated response function and the exponent z, describing the growing le

Yuri I. Ingster, Christophe Pouet, Alexandre B. Tsybakov

Given a training sample of size $m$ from a $d$-dimensional population, we wish to allocate a new observation $Z\in \R^d$ to this population or to the noise. We suppose that the difference between the distribution of the population and that of the noise is only in a shift, which is a sparse vector. For the Gaussian noise, fixed sample size $m$, and the dimens

Maurizio Dapor

A Monte Carlo scheme is described where the secondary electron generation has been incorporated. The initial position of a secondary electron due to Fermi sea excitation is assumed to be where the inelastic collision took place, while the polar and azimuth angles of secondary electrons can be calculated in two different ways. The first one assumes a random d

Alphonse P. Magnus

It is shown how to define difference equations on particular lattices $\{x_n\}$, $n\in\mathbb{Z}$, made of values of an elliptic function at a sequence of arguments in arithmetic progression (elliptic lattice). Solutions to special difference equations have remarkable simple interpolatory expansions. Only linear difference equations of first order are consid

Ying Wu, Zhao-Qing Zhang

In the framework of multiple-scattering theory, we show that the dispersion relations of certain electromagnetic (EM) and elastic metamaterials can be obtained analytically in the long-wavelength limit. Specific examples are given to the two-dimensional metamaterials with cylindrical inclusions arranged in square and triangular lattices. The role played by t

Josef Silhan

Let $M$ be a smooth manifold equipped with a conformal structure, $E[w]$ the space of densities with the the conformal weight $w$ and $D_{w,w+\de}$ the space of differential operators from $E[w]$ to $E[w+δ]$. Conformal quantization $Q$ is a right inverse of the principle symbol map on $D_{w,w+δ}$ such that $Q$ is conformally invariant and exists for all $w$.

D. Sokolovski, I. Puerto Gimenez, R. Sala Mayato

Hardy's paradox is analysed within Feynman's formulation of quantum mechanics. A transition amplitude is represented as a sum over virtual paths which different intermediate measurements convert into different sets of real pathways. Contradictory statements emerge when applying to the same statistical ensemble. The "strange" weak values resul

J. B. Roos, A. E. Orel, AA. Larson

The cross section for resonant ion-pair formation in the collision of low-energy electrons with HF^+ is calculated by the solution of the time-dependent Schrodinger equation with multiple coupled states using a wave packet method. A diabatization procedure is proposed to obtain the electronic couplings between quasidiabatic potentials of ^1Sigma^+ symmetry f

T Cokelaer, D Pathak

Most of the inspiralling compact binaries are expected to be circularized by the time their gravitational-wave signals enter the frequency band of ground-based detectors such as LIGO or VIRGO. However, it is not excluded that some of these binaries might still possess a significant eccentricity at a few tens of hertz. Despite this possibility, current search

Xiao-gang Yin, Cheng-ping Huang, Zhi-Qiang Shen, Qian-jin Wang

We studied experimentally and theoretically the optical transmission through asymmetrical holes of a metal film, which is constructed by introducing small protuberances to the sides of individual square holes. Due to the symmetry breaking of hole shape, an interesting transmission feature appears: both the Ag-glass (1, 0) and Ag-glass (1, 1) peaks split dist

Shinji Fukuhara, Yifan Yang

Let $f_1,...,f_d$ be an orthogonal basis for the space of cusp forms of even weight $2k$ on $Γ_0(N)$. Let $L(f_i,s)$ and $L(f_i,χ,s)$ denote the $L$-function of $f_i$ and its twist by a Dirichlet character $χ$, respectively. In this note, we obtain a ``trace formula&#39;&#39; for the values $L(f_i,χ,m)\overline{L(f_i,n)}$ at integers $m$ and $n$ with $0<m,n<

Iurii V. Gudyma, Artur Iu. Maksymov

Suppression of selection among broken-symmetry states has been found in double-well system resulting from two simultaneous correlated white noises, one additive and the other multiplicative. Symmetry-asymmetry-symmetry transition is re-entrant as a function of the additive noise intensity for small multiplicative noise.

Xiao-gang Yin, Cheng-ping Huang, Qian-jin Wang, Chao Zhang

The design, fabrication, and optical properties of a composite plasmonic structure, a two-dimentional array of split-ring resonators inserted into periodic square holes of a metal film, have been reported. A new type of transmission resonance, which makes a significant difference from the conventional peaks, has been suggested both theoretically and experime

D. Alpay, I. Gohberg, M. A. Kaashoek, L. Lerer

In the present paper we extend results of M.G. Krein associated to the spectral problem for Krein systems to systems with matrix valued accelerants with a possible jump discontinuity at the origin. Explicit formulas for the accelerant are given in terms of the matrizant of the system in question. Recent developments in the theory of continuous analogs of the

L. Fernández-Jambrina

FLRW models filled with just dark energy are shown to have a finite past, since causal geodesics cannot be extended beyond a certain proper time. It is shown that curvature measured along causal geodesics becomes infinity on travelling to the past, though curvature scalars tend to zero. Furthermore the time measured by free-falling observers from coincidence

M. Cattani, J. M. F. Bassalo

We made in this paper a brief analysis of the following statistics: Intermediate Statistics, Parastatistics, Fractionary Statistics and Gentileonic Statistics that predict the existence of particles which are different from bosons, fermions and maxwellons. We shown the fundamental hypothesis assumed in each one of the above mentioned statistics and their mai

Pal Choudhury Pabitra, Sahoo Sudhakar, Nayak Birendra Kumar, Hassan Sk. Sarif

In this paper we have defined two functions that have been used to construct different fractals having fractal dimensions between 1 and 2. More precisely, we can say that one of our defined functions produce the fractals whose fractal dimension lies in [1.58, 2) and rest function produce the fractals whose fractal dimension lies in (1, 1.58]. Also we tried t

Santanu Dey

We review how some multianalytic inner functions of the Beurling type theorem are associated to row contractions following works of G.Popescu. Motivated by a result on weak Markov dilations, we define a notion of characteristic function for ergodic and coisometric row contractions with a one-dimensional invariant subspace for the adjoints. Our characteristic

T. Banakh, M. Vovk, M. R. Wójcik

In a separably connected space any two points are contained in a separable connected subset. We show a mechanism that takes a connected bounded metric space and produces a complete connected metric space whose separablewise components form a quotient space isometric to the original space. We repeatedly apply this mechanism to construct, as an inverse limit,

P. Wojcik, B. J. Spisak, M. Woloszyn, J. Adamowski

The electron transport through the triple-barrier resonant tunnelling diode (TBRTD) have been studied by the self-consistent numerical method for the Wigner-Poisson problem. The electron flow through the TBRTD can be controlled by the gate voltage applied to one of the potential well regions. For different gate voltage values we have determined the current-v

Y. Yoshii

We consider a natural generalization of both locally finite irreducible root systems and extended affine root systems defined by Saito. We classify the systems.

Thomas Belhadj, Claire-Marie Simon, Thierry Amand, Pierre Renucci

We demonstrate optical control of the polarization eigenstates of a neutral quantum dot exciton without any external fields. By varying the excitation power of a circularly polarized laser in micro-photoluminescence experiments on individual InGaAs quantum dots we control the magnitude and direction of an effective internal magnetic field created via optical

A. Bagulya, A. Blondel, S. Borghi, G. Catanesi

The HARP experiment was designed to study hadron production in proton- nucleus collisions in the energy range of 1.5 GeV/c-15 GeV/c. The experiment was made of two spectrometers, a forward dipole spectrometer and a large-angle solenoid spectrometer. In the large-angle spectrometer the main tracking and particle identification is performed by a cylindrical Ti

A. Enciso, F. Finkel, A. Gonzalez-Lopez

We show that the density of energy levels of a wide class of finite-dimensional quantum systems tends to a Gaussian distribution as the number of degrees of freedom increases. Our result is based on a nontrivial modification of the classical central limit theorem, and is especially suited to models whose partition function is explicitly known. In particular,

V. Palchykov, C. von Ferber, R. Folk, Yu. Holovatch

The system of two scalar order parameters on a complex scale-free network is analyzed in the spirit of Landau theory. To add a microscopic background to the phenomenological approach we also study a particular spin Hamiltonian that leads to coupled scalar order behavior using the mean field approximation. Our results show that the system is characterized by

G. Coppola, F. La Barbera, M. Capaccioli

We present spherical, non-rotating, isotropic models of early-type galaxies with stellar and dark-matter components both described by deprojected Sersic density profiles, and prove that they represent physically admissible stable systems. Using empirical correlations and recent results of N-body simulations, all the free parameters of the models are expresse

José Antonio Belinchón

We study a massive cosmic strings with BII symmetries cosmological models in two contexts. The first of them is the standard one with a barotropic equation of state. In the second one we explore the possibility of taking into account variable \textquotedblleft constants\textquotedblright ($G$ and $Λ).$Both models are studied under the self-similar hypothesis

Gianpietro Summa

In this paper a new approach to perform step-drawdown tests in presented. Step-drawdown tests known so far are performed strictly keeping the value of the pumping rates constant through all the steps of the test. Current technology allows us to let the submerged electric pumps work at a specific revolution per minute (rpm) and allows us to suitably modify th

Sebastian Klein, Gudlaugur Thorbergsson, Laszlo Verhoczki

We prove that a function on an irreducible compact symmetric space M, which is not a sphere, is determined by its integrals over the shortest closed geodesics in M. We also prove a support theorem for the Funk transform on rank one symmetric spaces which are not spheres.

J. Agostinho Moreira, A. Almeida, W. S. Ferreira, M. R. Chaves

In this work we present a detailed study of the structural and lattice dynamic properties of Y-doped EuMnO3 ceramics (Eu1-xYxMnO3, with 0<x<0.55). A thorough analysis towards the correlation between both structural and Raman modes parameters has been undertaken. Our results provide evidence for two main structural distortions of MnO6 octahedra, arising from

Chenglong Jia, Jamal Berakdar

We study the dynamical interplay between ferroelectricity and magnetism in a multiferroic with a helical magnetic order. We show that the dynamical exchange-striction induces a biquadratic interaction between the spins and transverse phonons resulting in quantum fluctuations of the spontaneous ferroelectric polarization $\mathbf{P}$ in the ferroelectric phas

Rimantas Lazauskas

Elastic proton scattering on ${}^{3}{H}$ nucleus is studied inbetween p-% ${}^{3}{H}$ and n-${}^{3}{He}$ thresholds, in the energy region where $α$-particles first excited state is inbeded in the continuum. For this aim Faddeev-Yakubovski equations are solved in configuration space, fully considering effects due to the isospin breaking as well as rigorously

Z. Kovács, K. S. Cheng, T. Harko

The possibility of observationally discriminating between various types of neutron stars, described by different equations of state of the nuclear matter, as well as differentiating neutron stars from other types of exotic objects, like, for example, quark stars, is one of the fundamental problems in contemporary astrophysics. We consider and investigate car

Ashim K. Roy, Subodh K. Sharma, Ranjan Gupta

It is generally agreed that interstellar dust grains consist of two main components, namely, silicates and graphites. Some models, like MRN model, assume these grains to be homogeneous spheres following a power law size distribution. This paper presents, in the framework of Mie theory, a parametrization of extinction spectrum curves of the silicates and the

Georgios M. Nikolopoulos, Lawrence M. Ioannou

In the classical setting, public-key encryption requires randomness in order to be secure against a forward search attack, whereby an adversary compares the encryption of a guess of the secret message with that of the actual secret message. We show that this is also true in the information-theoretic setting -- where the public keys are quantum systems -- by

Kiryung Lee, Yoram Bresler

The rank minimization problem is to find the lowest-rank matrix in a given set. Nuclear norm minimization has been proposed as an convex relaxation of rank minimization. Recht, Fazel, and Parrilo have shown that nuclear norm minimization subject to an affine constraint is equivalent to rank minimization under a certain condition given in terms of the rank-re

Jean-Bernard Maillet, Emeric Bourasseau, Laurent Soulard, Jean Clerouin

We present several equilibrium methods that allow to compute isentropic processes, either during the compression or the release of the material. These methods are applied to compute the isentropic release of a shocked monoatomic liquid at high pressure and temperature. Moreover, equilibrium results of isentropic release are compared to the direct nonequilibr

Pat Kalyniak, Dmitriy Tseliakhovich

Little Higgs models may provide a viable alternative to supersymmetry as an extension of the Standard Model. After the introduction of a discrete $Z_2$ symmetry, dubbed T-parity into Little Higgs models they also contain a promising dark matter candidate. We investigate a heavy neutrino as a dark matter candidate in the Simplest Little Higgs with T-parity (S

Hong Ju Park, Ender Ayanoglu

We present and analyze the performance of constellation precoded beamforming. This multi-input multi-output transmission technique is based on the singular value decomposition of a channel matrix. In this work, the beamformer is precoded to improve its diversity performance. It was shown previously that while single beamforming achieves full diversity withou

Rory Barnes, Thomas R. Quinn, Jack J. Lissauer, Derek C. Richardson

We present N-body simulations of planetary accretion beginning with 1 km radius planetesimals in orbit about a 1 solar mass star at 0.4 AU. The initial disk of planetesimals contains too many bodies for any current N-body code to integrate; therefore, we model a sample patch of the disk. Although this greatly reduces the number of bodies, we still track in e

Jorgen Randrup

We construct a simple two-phase equation of state intended to resemble that of compressed baryon-rich matter and then introduce a gradient term in the compressional energy density to take account of fintie-range effects in non-uniform configurations. With this model we study the interface between the two coexisting phases and obtain estimates for the associa

Kazunori Nakayama

Recent measurements of cosmic-ray electron and positron fluxes by PAMELA and ATIC experiments may indicate the existence of annihilating dark matter with large annihilation cross section. We discuss its possible relation to other astrophysical/cosmological observations : gamma-rays, neutrinos, and big-bang nucleosynthesis. It is shown that they give stringen

Nayantara Gupta

Air shower experiments have detected cosmic ray events of energies upto 300 EeV. Most likely these cosmic rays have originated from compact objects. Their exact sources are yet to be identified. It has been suggested before that gamma ray bursts are possible sources of ultra-high energy cosmic rays. The two models of gamma ray burst emissions most often disc

Ville Pietilä, Mikko Möttönen

We demonstrate theoretically that using standard external magnetic fields, one can imprint point-like topological defects to the spin texture of a dilute Bose-Einstein condensate. Symmetries of the condensate order parameter render this topological defect to be accompanied with a vortex filament corresponding to the Dirac string of a magnetic monopole. The v

Ralf Toenjes, Bernd Blasius

The Kuramoto phase diffusion equation is a nonlinear partial differential equation which describes the spatio-temporal evolution of a phase variable in an oscillatory reaction diffusion system. Synchronization manifests itself in a stationary phase gradient where all phases throughout a system evolve with the same velocity, the synchronization frequency. The

Wenan Guo, Youjin Deng, Henk W. J. Blote

We derive the scaling dimension associated with crossing bonds in the random-cluster representation of the two-dimensional Potts model, by means of a mapping on the Coulomb gas. The scaling field associated with crossing bonds appears to be irrelevant, on the critical as well as on the tricritical branch. The latter result stands in a remarkable contrast wit

Xin-zhou Li, Chang-bo Sun, Ping Xi

We apply the statefinder diagnostic to the torsion cosmology, in which an accounting for the accelerated universe is considered in term of a Riemann-Cartan geometry: dynamic scalar torsion. We find that there are some typical characteristic of the evolution of statefinder parameters for the torsion cosmology that can be distinguished from the other cosmologi

Pin Yu

We show the existence of a Hawking vector field in a full neighborhood of a local, regular, bifurcate, non-expanding horizon embedded in a smooth Einstein-Maxwell space-time without assuming the underlying space-time is analytic. It extends one result of Friedrich, Rácz and Wald, which was limited to the interior of the black hole region. Moreover, we also s

M. B. Pracy, H. Kuntschner, W. J. Couch, C. Blake

We have used the GMOS instrument on the Gemini-South telescope to obtain spatially-resolved two-colour imaging and IFU spectroscopy of a sample of ten nearby E+A galaxies. Surface brightness profiles measured using our imaging data show the isophotal profiles of our sample are generally r^{1/4}-like, consistent with a sample dominated by early-type galaxies.

C. P. Dettmann, G. V. Morozov, M. Sieber, H. Waalkens

Circular microresonators (microdisks) are micron sized dielectric disks embedded in a material of lower refractive index. They possess modes with complex eigenvalues (resonances) which are solutions of analytically given transcendental equations. The behavior of such eigenvalues in the small opening limit, i.e. when the refractive index of the cavity goes to

Andrew J S Hamilton, Gavin Polhemus

We illustrate and discuss the view seen by an observer inside the horizon of a Schwarzschild black hole. The view as the observer approaches the central singularity is of particular interest because, according to ideas arising from &#34;observer complementarity,&#34; points in opposite directions along the observer&#39;s past lightcone are at &#34;the edge o

Laetitia Gauvin, Jean Vannimenus, Jean-Pierre Nadal

The collective behavior in a variant of Schelling&#39;s segregation model is characterized with methods borrowed from statistical physics, in a context where their relevance was not conspicuous. A measure of segregation based on cluster geometry is defined and several quantities analogous to those used to describe physical lattice models at equilibrium are i

Paolo Lipparini

We generalize to the relations $(λ, μ) \stackrelκ{\Rightarrow} (λ&#39;, μ&#39;)$ and $\alm (λ, μ) \stackrelκ{\Rightarrow} \alm (λ&#39;, μ&#39;)$ some results obtained in Parts II and IV. We also present a multi-cardinal version.

Jake D. Koralek, Chris Weber, Joe Orenstein, Andrei Bernevig

According to Noethers theorem, for every symmetry in nature there is a corresponding conservation law. For example, invariance with respect to spatial translation corresponds to conservation of momentum. In another well-known example, invariance with respect to rotation of the electrons spin, or SU(2) symmetry, leads to conservation of spin polarization. For

Luis F. Alday, Juan Maldacena

In this note we consider minimal surfaces in three dimensional anti-de Sitter space that end at the AdS boundary on a polygon given by a sequence of null segments. The problem can be reduced to a certain generalized Sinh-Gordon equation and to SU(2) Hitchin equations. The mathematical problem to be solved arises also in the context of the moduli space of cer

Adrian Dumitru, Yun Guo, Michael Strickland

We determine viscosity corrections to the retarded, advanced and symmetric gluon self energies and to the static propagator in the weak-coupling &#34;hard loop&#34; approximation to high-temperature QCD. We apply these results to calculate the imaginary part of the heavy-quark potential which is found to be smaller (in magnitude) than at vanishing viscosity.

Martin Z. Bazant, Mustafa Sabri Kilic, Brian D. Storey, Armand Ajdari

The venerable theory of electrokinetic phenomena rests on the hypothesis of a dilute solution of point-like ions near a weakly charged surface, whose potential relative to the bulk is of order the thermal voltage ($kT/e \approx 25$ mV at room temperature). In nonlinear electrokinetic phenomena, such as AC or induced-charge electro-osmosis (ACEO, ICEO) and in

D. Cebra

Results from a one day $\sqrt{s_{NN}} = 19.6$ GeV Au+Au test run at RHIC using the STAR detector are presented. The quality of these results from only 175,000 triggered events demonstrates some of STAR's physics capabilities for the upcoming beam energy scan at RHIC. From these 19.6 GeV Au+Au collisions, we have analyzed the transverse mass spectra of $\pi^{

Anatoly E. Dementyev, David G. Cory, Chandrasekhar Ramanathan

Single crystal silicon is an excellent system in which to explore dynamic nuclear polarization (DNP), as it exhibits a continuum of properties from metallic to insulating as a function of doping concentration and temperature. At low doping concentrations DNP has been observed to occur via the solid effect, while at very high doping concentrations an Overhaus

C. Jin, C. Done, M. Ward, M. Gierliński

We have carried out a survey of long 50ks XMM-Newton observations of a sample of bright, variable AGN. We found a distinctive energy dependence of the variability in RXJ0136.9-3510 where the fractional variability increases from 0.3 to 2 keV, and then remains constant. This is in sharp contrast to other AGN where the X-ray variability is either flat or falli

Shin&#39;ichiro Ando

Dark matter annihilation in galactic substructure would imprint characteristic angular signatures on the all-sky map of the diffuse gamma-ray background. We study the gamma-ray background anisotropy due to the subhalos and discuss detectability at Fermi Gamma-ray Space Telescope. We derive analytic formulae that enable to directly compute the angular power s

Andrea V. Maccio&#39;, Xi Kang, Fabio Fontanot, Rachel S. Somerville

We study the luminosity function and the radial distribution of satellite galaxies within Milky Way sized haloes as predicted in Cold Dark Matter based models of galaxy formation, making use of numerical N-body techniques as well as three different semi-analytic model (SAMs) galaxy formation codes. We extract merger trees from very high-resolution dissipatio

Robert M. Ziff

The growth of two-dimensional lattice bond percolation clusters through a cooperative Achlioptas-type of process, where the choice of which bond to occupy next depends upon the masses of the clusters it connects, is shown to go through an explosive, first-order kinetic phase transition with a sharp jump in the mass of the largest cluster as the number of bon

Shuang-Yong Zhou, Edmund J. Copeland, Paul M. Saffin

Modified gravity theories with the Gauss-Bonnet term $G=R^2-4R^{μν}R_{μν}+R^{μνρσ}R_{μνρσ}$ have recently gained a lot of attention as a possible explanation of dark energy. We perform a thorough phase space analysis on the so-called $f(G)$ models, where $f(G)$ is some general function of the Gauss-Bonnet term, and derive conditions for the cosmological viab

Oleksiy Dovgoshey, Fahreddin Abdullayev, Mehmet Kuchukaslan

We find necessary and sufficient conditions under which an arbitrary metric space $X$ has a unique pretangent space at the marked point $a\in X$. Key words: Metric spaces; Tangent spaces to metric spaces; Uniqueness of tangent metric spaces; Tangent space to the Cantor set.

D. Parshall, K. A. Lokshin, Jennifer Niedziela, A. D. Christianson

Superconductivity appears to compete against the spin-density-wave in Fe pnictides. However, optimally cobalt doped samples show a quasi-two-dimensional spin excitation centered at the (0.5, 0.5, L) wavevector, &#34;the spin resonance peak&#34;, that is strongly tied to the onset of superconductivity. By inelastic neutron scattering on single crystals we sho

S. Mazoyer, F. Ebert, G. Maret, P. Keim

We investigate the dynamics of a glass forming 2D colloidal mixture and show the existence of collective motions of the particles. We introduce a mean square displacement MSD with respect to the nearest neighbors which shows remarkable deviations from the usual MSD quantifying the individual motion of our particles. Combined with the analysis of the self par

Elena R. Loubenets

We introduce a general condition sufficient for the validity of the original Bell inequality (1964) in a local hidden variable (LHV) frame. This condition can be checked experimentally and incorporates only as a particular case the assumption on perfect correlations or anticorrelations usually argued for this inequality in the literature. Specifying this gen

B. M. Rodriguez-Lara, R. Jauregui

We propose a scheme to split a cloud of cold non-interacting neutral atoms based on their dipole interaction with a single structured light beam which exhibits parabolic cylindrical symmetry. Using semiclassical numerical simulations, we establish a direct relationship between the general properties of the light beam and the relevant geometric and kinematic

Borzumehr Toloui, Leslie E. Ballentine

We study a system of two coupled kicked rotors, both classically and quantum mechanically, for a wide range of coupling parameters. This was motivated by two published reports, one of which reported quantum localization, while the other reported diffusion. The classical systems are chaotic, and exhibit normal diffusive behavior. In the quantum systems, we fo

Jose Beltran Jimenez, Antonio L. Maroto

We consider electromagnetic field quantization in an expanding universe. We find that the covariant (Gupta-Bleuler) method exhibits certain difficulties when trying to impose the quantum Lorenz condition on cosmological scales. We thus explore the possibility of consistently quantizing without imposing such a condition. In this case there are three physical

Z. P. Jin, D. Xu, S. Covino, P. D&#39;Avanzo

We present the prompt BAT and afterglow XRT data of Swift-discovered GRB081109A up to ~ 5\times 10^5 sec after the trigger, and the early ground-based optical follow-ups. The temporal and spectral indices of the X-ray afterglow emission change remarkably. We interpret this as the GRB jet first traversing the freely expanding supersonic stellar wind of the pr

W. Schnelle, A. Leithe-Jasper, R. Gumeniuk, U. Burkhardt

The magnetism in SrFe2As2 can be suppressed by electron doping through a small substitution of Fe by Co or Ni, giving way to superconductivity. We demonstrate that a massive substitution of Fe by isovalent ruthenium similarly suppresses the magnetic ordering in SrFe2-xRuxAs2 and leads to bulk superconductivity for 0.6 <= x <= 0.8. Magnetization, electrical r

A. van Hameren, C. G. Papadopoulos, R. Pittau

An algorithm, based on the OPP reduction method, to automatically compute any one-loop amplitude, for all momentum, color and helicity configurations of the external particles, is presented. It has been implemented using the tree-order matrix element code HELAC and the OPP reduction code CutTools. As a demonstration of the potential of the current implementa

Renata Kallosh

We construct the generating functional for the light-cone superfield amplitudes in a chiral momentum superspace. It generates the n-point particle amplitudes which on shell are equivalent to the covariant ones. Based on the action depending on unconstrained light-cone chiral scalar superfield, this functional provides a regular d=4 QFT path integral derivati

Mark Hovey, Keir Lockridge

The primary object of this paper is to prove the conjecture of the authors from a previous paper, explaining how to recover the weak dimension of a ring from its derived category. In the process, we develop a theory of weak dimension, which we call ghost dimension, for the generalized rings, known as ring spectra, that arise in algebraic topology.

A. Gehrmann-De Ridder, T. Gehrmann, E. W. N. Glover, G. Heinrich

We compute the next-to-next-to-leading order (NNLO) QCD corrections to the first five moments of six event shape variables related to three-particle final states in electron-positron annihilation; the thrust, the heavy jet mass, the C-parameter, the wide and total jet broadenings and the three-to-two-jet transition parameter in the Durham algorithm Y3. The N

Roman Antos, Yoshichika Otani

We present a possibility to switch the chirality of a spin vortex occurring in a magnetic nanodisk by applying a uniform in-plane field pulse, based on optimizing its strength and duration. The related spin-dynamical process, investigated by micromagnetic simulations, consists of several stages. After applying the field, the original vortex is expelled from

Alexander Rahm, Mathias Fuchs

We show that a cellular complex described by Floege allows to determine the integral homology of the Bianchi groups $PSL_2(O_{-m})$, where $O_{-m}$ is the ring of integers of an imaginary quadratic number field $\rationals[\sqrt{-m}]$ for a square-free natural number $m$. We use this to compute in the cases m = 5, 6, 10, 13 and 15 with non-trivial class grou

Thomas Reiter

The search for the Higgs boson and for physics beyond the Standard Model are the major motivations behind the LHC experiment. In many scenarios the success of the experiment depends on the knowledge of signal and background event rates at least at one-loop precision. We present the approach of the \texttt{GOLEM} collaboration to build a highly automated fram

Dinesh Singh, Nader Mobed

The possibility of a frame-induced violation of Lorentz invariance due to non-inertial spin-1/2 particle motion is explored in detail for muon decay while in orbit near the event horizon of a microscopic Kerr black hole. It is explicitly shown that kinematic and curvature contributions to the muon&#39;s decay spectrum--in the absence of any unforeseen proces

Stephen G. Low

The quantum phase leads to projective representations of symmetry groups in quantum mechanics. The projective representations are equivalent to the unitary representations of the central extension of the group. A celebrated example is Wigner&#39;s formulation of special relativistic quantum mechanics as the projective representations of the inhomogeneous Lor

Joyce C. Myers, Michael C. Ogilvie

We minimize the one-loop effective potential for SU(N) gauge theories including fermions with finite mass in the fundamental (F), adjoint (Adj), symmetric (S), and antisymmetric (AS) representations. We calculate the phase diagram on S^1 x R^3 as a function of the length of the compact dimension, beta, and the fermion mass, m. We consider the effect of perio

I. Schmelzer

Pure interpretations of quantum theory, which reject the classical part of the Copenhagen interpretation without adding new structure to it&#39;s quantum part, are not viable. This is a consequence of a non-uniqueness result for the canonical operators.

Dr. Daniel Skodlerack

This article answers a question that naturally arises from the articles by Grabitz and Broussous &#34;Pure elements and intertwining classes of simple strata in local central simple algebras&#34; and Broussous and Lemaire &#34;Buildings of GL(m,D) and Centralizers&#34;. For an Azumaya-Algebra A over a non-Archimedean local field F, Grabitz and Broussous have

Dr. Daniel Skodlerack

This notes are additional remarks to an article of Broussous and Stevens [arXiv:math/0402228v1]. We consider a unitary group G over a non-Archimedean local field k_0 of residue characteristic different from two and an element β of the Lie algebra \mf{g} of G. Let H be the centralizer of β in G. We further assume k_0[β] to be semisimple. We prove that there i

L. Vitagliano

We define partial differential (PD in the following), i.e., field theoretic analogues of Hamiltonian systems on abstract symplectic manifolds and study their main properties, namely, PD Hamilton equations, PD Noether theorem, PD Poisson bracket, etc.. Unlike in standard multisymplectic approach to Hamiltonian field theory, in our formalism, the geometric str

A. Andreanov, G. Biroli, J. -P. Bouchaud

We derive the Mode Coupling Theory (MCT) of the glass transition as a Landau theory, formulated as an expansion of the exact dynamical equations in the difference between the correlation function and its plateau value. This sheds light on the universality of MCT predictions. While our expansion generates higher order non-local corrections that modify the sta

Jens O. Andersen, Lars Kyllingstad, Lars E. Leganger

We calculate the pressure of massless $ϕ^4$-theory to order $g^8\log(g)$ at weak coupling. The contributions to the pressure arise from the hard momentum scale of order $T$ and the soft momentum scale of order $gT$. Effective field theory methods and dimensional reduction are used to separate the contributions from the two momentum scales: The hard contribut