November 2007 arXiv papers — page 39

Willemien Visser

This text presents the cognitive-ergonomics approach to design, in both its individual and collective form. It focuses on collective design with respect to individual design. The theoretical framework adopted is that of information processing, specified for design problems. The cognitive characteristics of design problems are presented: the effects of their

N. D'Ascenzo, A. Eggemann, E. Garutti

A new Geiger mode avalanche photodiode, the Micro Pixel Photon Counter (MPPC), was recently released by Hamamatsu. It has a high photo-detection efficiency in the 420 nm spectral region. This product can represent an elegant candidate for the design of a high granularity scintillator based hadron calorimeter for the International Linear Collider. In fact, th

G. Dileo, A. Lotta

In this paper we classify the simply connected, spherical pseudohermitian manifolds whose Webster metric is CR-symmetric.

Emanuele Alesci, Carlo Rovelli

In a previous article we have show that there are difficulties in obtaining the correct graviton propagator from the loop-quantum-gravity dynamics defined by the Barrett-Crane vertex amplitude. Here we show that a vertex amplitude that depends nontrivially on the intertwiners can yield the correct propagator. We give an explicit example of asymptotic behavio

Christian R. Kaiser, Philip N. Best

This erratum corrects a number of formulae containing mistakes in the paper 'Luminosity function, sizes and FR dichotomy of radio-loud AGN', 2007, MNRAS, v. 381, p.1548. The corrections do not alter any of the conclusions in the original paper.

D. A. Abdushukurov, D. V. Bondarenko, Kh. Kh. Muminov, D. Yu. Chistyakov

We consider the results of modeling of the efficiency of registration of thermal neutrons by the converters, which are made from natural gadolinium and its 157 isotope foils. Efficiency for a case of falling of neutrons under various angles to a plane of converters is calculated. It is shown, that at small angles of falling of neutrons to a plane of converte

Fabio Dahia, Carlos Romero, Lucio F. P. Silva, Reza Tavakol

We study the classical geodesic motions of nonzero rest mass test particles and photons in (3+1+n)- dimensional warped product spaces. An important feature of these spaces is that they allow a natural decoupling between the motions in the (3+1)-dimensional spacetime and those in the extra n dimensions. Using this decoupling and employing phase space analysis

I. O. Cherednikov, N. G. Stefanis

A range of issues pertaining to the use of Wilson lines in integrated and transverse-momentum dependent (TMD) parton distribution functions (PDF) is discussed. The relation between gauge invariance and the renormalization properties of the Wilson-line integrals is given particular attention. Using an anomalous-dimensions based analysis in the light-cone gaug

Paul E. Gunnells, Dan Yasaki

Let F be a real quadratic field with ring of integers O and with class number 1. Let Gamma be a congruence subgroup of GL_2 (O). We describe a technique to compute the action of the Hecke operators on the cohomology H^3 (Gamma; C). For F real quadratic this cohomology group contains the cuspidal cohomology corresponding to cuspidal Hilbert modular forms of p

M. Klein-Wolt, M. van der Klis

From a uniform analysis of a large (8.5 Ms) Rossi X-ray Timing Explorer data set of Low Mass X-ray Binaries, we present a complete identification of all the variability components in the power spectra of black holes in their canonical states. It is based on gradual frequency shifts of the components observed between states, and uses a previous identification

Tolga Girici, Chenxi Zhu, Jonathan R. Agre, Anthony Ephremides

In this work we propose an efficient resource allocation algorithm for OFDMA based wireless systems supporting heterogeneous traffic. The proposed algorithm provides proportionally fairness to data users and short term rate guarantees to real-time users. Based on the QoS requirements, buffer occupancy and channel conditions, we propose a scheme for rate requ

Walter Schachermayer, Josef Teichmann

We compare the option pricing formulas of Louis Bachelier and Black-Merton-Scholes and observe -- theoretically as well as for Bachelier's original data -- that the prices coincide very well. We illustrate Louis Bachelier's efforts to obtain applicable formulas for option pricing in pre-computer time. Furthermore we explain -- by simple methods from

Luciano da Fontoura Costa

A good deal of the connectivity of complex networks can be characterized in terms of their constituent paths and hubs. For instance, the Barabási-Albert model is known to incorporate a significative number of hubs and relatively short paths. On the other hand, the Watts-Strogatz model is underlain by a long path and almost complete absence of hubs. The prese

D. S. O'Brien

There has been much recent research into polarizing an antiproton beam, instigated by the recent proposal from the PAX (Polarized Antiproton eXperiment) project at GSI Darmstadt. It plans to polarize an antiproton beam by repeated interaction with a polarized internal target in a storage ring. The method of polarization buildup by spin filtering requires man

Tolga Girici, Chenxi Zhu, Jonathan R. Agre, Anthony Ephremides

In this work we consider the problem of downlink resource allocation for proportional fairness of long term received rates of data users and quality of service for real time sessions in an OFDMA-based wireless system. The base station allocates available power and bandwidth to individual users based on long term average received rates, QoS based rate constra

Walter Schachermayer, Josef Teichmann

We prove that $c$-cyclically monotone transport plans $π$ optimize the Monge-Kantorovich transportation problem under an additional measurability condition. This measurability condition is always satisfied for finitely valued, lower semi-continuous cost functions. In particular, this yields a positive answer to Problem 2.25 in C. Villani's book. We empha

Mikyoung Lim, Kaouthar Louati, Habib Zribi

We consider the problem of determining the boundary perturbations of an object from far-field electric or acoustic measurements. Assuming that the unknown object boundary is a small perturbation of a circle, we develop a linearized relation between the far-field data that result from fixed Dirichlet boundary conditions, entering as parameters, and the shape

Cecilia Nardini, Balazs Kozma, Alain Barrat

We investigate different opinion formation models on adaptive network topologies. Depending on the dynamical process, rewiring can either (i) lead to the elimination of interactions between agents in different states, and accelerate the convergence to a consensus state or break the network in non-interacting groups or (ii) counter-intuitively, favor the exis

Carsten Honerkamp

Motivated by the surge in research activities on graphene, we investigate instabilities of electrons on the honeycomb lattice, interacting by onsite and nearest-neighbor terms, using a renormalization group scheme. Near half band-filling, critical minimal interaction strengths are required for instabilities toward antiferromagnetic or charge-density wave ord

A. Filinov, J. Böning, M. Bonitz, Yu. E. Lozovik

When a few tens of charged particles are trapped in a spherical electrostatic potential at low temperature they form concentric shells resembling atoms. These ``artificial atoms'' can be easily controlled by varying the confinement strength. We analyze such systems for the case that the particles are bosons and find superfluid behavior which even per

A. N. Ogurtsov, N. Yu. Masalitina, O. N. Bliznjuk

Thermodynamic parameters of thermal inactivation of excitonically induced defect formation in rare-gas solids have been obtained from the fitting of the temperature dependences of defect formation rates, which were measured under selective photoexcitation by synchrotron radiation.

E. V. Deviatov, A. Lorke, W. Wegscheider

We experimentally study equilibration across the sample edge at high fractional filling factors 4/3, 5/3 under experimental conditions, which allow us to obtain high imbalance conditions. We find a lack of the full equilibration across the edge even in the flat-band situation, where no potential barrier survives at the sample edge. We interpret this result a

Marcos P. Cavalcante

Given a closed subset $\La$ of the open unit ball $B_1\subset \real^n$, $n \geq 3$, we will consider a complete Riemannian metric $g$ on $\bar{B_1} \setminus \La$ of constant scalar curvature equal to $n(n-1)$ and conformally related to the Euclidean metric. In this paper we prove that every closed Euclidean ball $\bar{B} \subset B_1\setminus \La$ is convex

Nabin Kumar Jana

In this thesis, we consider several Random Energy Models. This includes Derrida's Random Energy Model (REM) and Generalized Random Energy Model (GREM) and a nonhierarchical version (BK-GREM) by Bolthausen and Kistler. The limiting free energy in all these models along with Word GREM, a model proposed by us, turn out to be a cute consequence of large devi

R. G. Nazmitdinov, N. S. Simonovic

Using the exactly solvable excitation spectrum of two-electron quantum dots with parabolic potential, we show that the inclusion of the vertical extension of the quantum dot provides a consistent description of the experimental findings of Nishi et al. [Phys.Rev.B75, 121301(R) (2007)]. We found that the second singlet-triplet transition in the ground state i

S. Getfert, P. Reimann

The forced rupture of single chemical bonds under external load is addressed. A general framework is put forward to optimally utilize the experimentally observed rupture force data for estimating the parameters of a theoretical model. As an application we explore to what extent a distinction between several recently proposed models is feasible on the basis o

G. Scolarici, L. Solombrino

We show that the complex projections of time-dependent $η$-quasianti-Hermitian quaternionic Hamiltonian dynamics are complex stochastic dynamics in the space of complex quasi-Hermitian density matrices if and only if a quasistationarity condition is fulfilled, i. e., if and only if $η$ is an Hermitian positive time-independent complex operator. An example is

P. W. Goldberg, P. Polpinit

We study a class of games in which a finite number of agents each controls a quantity of flow to be routed through a network, and are able to split their own flow between multiple paths through the network. Recent work on this model has contrasted the social cost of Nash equilibria with the best possible social cost. Here we show that additional costs are in

D. Mannix, D. F. McMorrow, R. A. Ewings, A. T. Boothroyd

We report on an extensive investigation of the multiferroic compound TbMnO$_3$. Non-resonant x-ray magnetic scattering (NRXMS) revealed a dominant $A$-type domain. The temperature dependence of the intensity and wavevector associated with the incommensurate magnetic order was found to be in good agreement with neutron scattering data. XRS experiments were pe

Andreas Juttner

CKM-unitarity, direct and indirect CP-violation and the ΔI=1/2 rule in full lattice QCD are the focus of this talk. To this end I will discuss and compare recent lattice results for leptonic, semi-leptonic and non-leptonic decays of the kaon and neutral kaon mixing and I will motivate current best estimates f_K/f_π=1.198(10), f_+^{Kπ}(0)=0.964(5) and \hat{B}

Asmaa Abada, Irene Hidalgo

We analyse the lepton sector of the Left-Right Twin Higgs Model. This model offers an alternative way to solve the "little hierarchy" problem of the Standard Model. We show that one can achieve an effective see-saw to explain the origin of neutrino masses and that this model can accommodate the observed neutrino masses and mixings. We have also studi

Rodion Stepanov, Franck Plunian

With a non local shell model of magnetohydrodynamic turbulence we investigate numerically the turbulent dynamo action for low and high magnetic Prandtl numbers ($Pm$). The results obtained in the kinematic regime and along the way to dynamo saturation are understood in terms of a phenomenological approach based on the local ($Pm\ll 1$) or non local ($Pm\gg 1

Shu-Yu Hsu

In this paper we will prove a maximum principle for the solutions of linear parabolic equation on complete non-compact manifolds with a time varying metric. We will prove the convergence of the Neumann Green function of the conjugate heat equation for the Ricci flow in $B_k\times (0,T)$ to the minimal fundamental solution of the conjugate heat equation as $k

Prasun Dutta, Ayesha Begum, Somnath Bharadwaj, Jayaram N. Chengalur

We have measured the HI power spectrum of the nearly face-on spiral galaxy NGC628 (M74) using a visibility based estimator. The power spectrum is well fitted by a power law $P(U)=AU^α$, with $α=- 1.6\pm0.2$ over the length scale $800 {\rm pc} {\rm to} 8 {\rm kpc}$. The slope is found to be independent of the width of the velocity channel. This value of the s

Viorel Iftimie, Marius Mantoiu, Radu Purice

We prove the analog of the Cwickel-Lieb-Rosenblum estimation for the number of negative eigenvalues of a relativistic Hamiltonian with magnetic field $B\in C^\infty_{\rm{pol}}(\mathbb R^d)$ and an electric potential $V\in L^1_{\rm{loc}}(\mathbb R^d)$, $V_-\in L^d(\mathbb R^d)\cap L^{d/2}(\mathbb R^d)$. Compared to the nonrelativistic case, this estimation in

Myung Gyoon Lee, Ho Seong Hwang, Sang Chul Kim, Hong Soo Park

We present a kinematic analysis of the globular cluster(GC) system in M31. Using the photometric and spectroscopic database of 504 GCs, we have investigated the kinematics of the M31 GC system. We find that the all GC system shows strong rotation, with rotation amplitude of v_rot~190km/s, and that a weak rotation persists even for the outermost samples at |Y

Thierry Daudé, François Nicoleau

In this paper, we study inverse scattering of massless Dirac fields that propagate in the exterior region of a Reissner-Nordström black hole. Using a stationary approach we determine precisely the leading terms of the high-energy asymptotic expansion of the scattering matrix that, in turn, permit us to recover uniquely the mass of the black hole and its char

Willemien Visser

This article presents a cognitively oriented viewpoint on design. It focuses on cognitive, dynamic aspects of real design, i.e., the actual cognitive activity implemented by designers during their work on professional design projects. Rather than conceiving de-signing as problem solving - Simon's symbolic information processing (SIP) approach - or as a r

Willemien Visser

This paper focuses on the use of knowledge possessed by designers. Data collection was based on observations (by the cognitive ergonomics researcher) and simultaneous verbalisations (by the designers) in empirical studies conducted in the context of industrial design projects. The contribution of this research is typical of cognitive ergonomics, in that it p

Hugues Chaté, Francesco Ginelli, Guillaume Grégoire

In this comment we show that the transition to collective motion in Vicsek-like systems with angular noise remain discontinuous for large velocity values. Thus, the networks studied by Aldana {\et al.} [Phys. Rev. Lett. {\bf 98}, 095702 (2007)] at best constitute a singular, large velocity limit of these systems.

Anatoly Yu. Smirnov, Lev G. Mourokh, Franco Nori

We examine a simple model of proton pumping through the inner membrane of mitochondria in the living cell. We demonstrate that the pumping process can be described using approaches of condensed matter physics. In the framework of this model, we show that the resonant Förster-type energy exchange due to electron-proton Coulomb interaction can provide an unidi

Viktor Dubrovich, Anisa Bajkova, Vladimir Khaikin

Spectral Spatial Fluctuations (SSF) of the Cosmic Microwave Background Radiation (CMBR) temperature are considered as a result of an interaction of primordial atoms and molecules with CMBR in proto-objects moving with peculiar velocities relative to the CMBR. Expected optimistic values of $ΔT/T$ are 2x10^{-5}--2x10^{-6}$ for SSF caused by HeH$^+$ at z =20-30

Dmitri V. Fursaev

In a quantum gravity theory the entropy of entanglement $S$ between the fundamental degrees of freedom spatially divided by a surface is discussed. The classical gravity is considered as an emergent phenomenon and arguments are presented that: 1) $S$ is a macroscopical quantity which can be determined without knowing a real microscopical content of the funda

Chun-Lai Ren, Yu-qiang Ma

Membrane organization is essential for cellular functions such as signal transduction and membrane trafficking. A major challenge is to understand the lateral heterogeneous structures in membranes and membrane fluidity in the presence of inclusions. Based on a considerable amount of experimental evidence for lateral organization of lipid membranes which shar

Laurent Brunel, Alice Brun, Patrik Snabre, Luca Cipelletti

We describe an extension of multi-speckle diffusing wave spectroscopy adapted to follow the non-stationary microscopic dynamics in drying films and coatings in a very reactive way and with a high dynamic range. We call this technique "Adaptive Speckle Imaging Interferometry". We introduce an efficient tool, the inter-image distance, to evaluate the s

Iztok Pizorn, Tomaz Prosen, Stefan Mossmann, Thomas H. Seligman

We study the properties of a two-body random matrix ensemble for distinguishable spins. We require the ensemble to be invariant under the group of local transformations and analyze a parametrization in terms of the group parameters and the remaining parameters associated with the "entangling" part of the interaction. We then specialize to a spin chai

E. Fredericks, F. M. Mahomed, E. Momoniat, Asghar Qadir

Given a space it is easy to obtain the system of geodesic equations on it. In this paper the inverse problem of reconstructing the space from the geodesic equations is addressed. A procedure is developed for obtaining the metric tensor from the Christoffel symbols. The procedure is extended for determining if a second order quadratically semi-linear system c

A. Fukuda, D. Terasawa, M. Morino, K. Iwata

We investigate a domain structure of pseudospins, a soliton lattice in the bilayer quantum Hall state at total Landau level filling factor $ν=1$, in a tilted magnetic field, where the pseudospin represents the layer degree of freedom. An anomalous peak in the magnetoresistance $R_{xx}$ appears at the transition point between the commensurate and incommensura

F. M. Mahomed, I. Naeem, Asghar Qadir

We provide linearizability criteria for a class of systems of third-order ordinary differential equations (ODEs) that is cubically semi-linear in the first derivative, by differentiating a system of second-order quadratically semi-linear ODEs and using the original system to replace the second derivative. The procedure developed splits into two cases, those

Fazal M. Mahomed, Asghar Qadir

Using geometric methods for linearizing systems of second order cubically semi-linear ordinary differential equations, we extend to the third order by differentiating the second order equation. This yields criteria for linearizability of a class of third order semi-linear ordinary differential equations, which is distinct from the classes available in the li

F. M. Mahomed, Asghar Qadir

Invariant linearization criteria of square systems of second-order quadratically semi-linear ordinary differential equations (ODEs) that can be represented as geodesic equations are extended to square systems of ODEs cubically nonlinear in the first derivatives. It is shown that there are two branches for the linearization problem via point transformations f

Zuhuan Yu, Xianqing Jost-Li, Qingzhong Li, Jintao Lv

We investigate the differential geometry of bipartite quantum states. In particular the manifold structures of pure bipartite states are studied in detail. The manifolds with respect to all normalized pure states of arbitrarily given Schmidt ranks or Schmidt coefficients are explicitly presented. The dimensions of the related manifolds are calculated.

Sergio Albeverio, Shao-Ming Fei, Debashish Goswami

We investigate the equivalence of quantum mixed states under local unitary transformations. For a class of rank-two mixed states, a sufficient and necessary condition of local equivalence is obtained by giving a complete set of invariants under local unitary transformations, such that two states in this class are locally equivalent if and only if all these i

Ghulam Shabbir, Shaukat Iqbal

A study of proper conformal vector field in non conformally flat cylindrically symmetric static space-times is given by using direct integration technique. Using the above mentioned technique we have shown that a very special class of the above space-time admits proper conformal vector field.

K. V. Shajesh, Kimball A. Milton, Prachi Parashar, Jeffrey A. Wagner

We have recently demonstrated that Casimir energy due to parallel plates, including its divergent parts, falls like conventional mass in a weak gravitational field. The divergent parts were suitably interpreted as renormalizing the bare masses of the plates. Here we corroborate our result regarding the inertial nature of Casimir energy by calculating the cen

Shoji Tsuboi

Let X be a complex algebraic manifold of dimension n+1 embedded in a sufficiently higher dimensional complex projective space, and Y a generic hyperplane section of X. We describe the mixed Hodge structure on H^p(X-Y,C) and the Hodge filtration of the middle primitive cohomology group H^n(Y,C)_0 of Y in terms of rational integrals on X. (Key words: Primitive

L. I. Korovin, I. G. Lang, S. T. Pavlov

Reflectance, transmittance and absorbance of a symmetric light pulse, the carrying frequency of which is close to the frequency of interband transitions in a quantum well, are calculated. Energy levels of the quantum well are assumed discrete, and two closely located excited levels are taken into account. The theory is applicable for the quantum wells of arb

Junichiro Miura, Masahiro Tsujimoto, Yohko Tsuboi, Yoshitomo Maeda

We report a serendipitous detection of an intense X-ray flare from the Tycho reference source HD 161084 during a Suzaku observation of the Galactic Center region for 20 ks. The X-ray Imaging Spectrometer (XIS) recorded a flare from this A1-type dwarf or subgiant star with a flux of 1.4x10^{-12} erg s^{-1} cm^{-2} (0.5--10 keV) and a decay time scale of 0.5 h

Yina Wu, Weiqiang Lin

In this paper, we complete the classification of the {\bf Z}-graded modules of the intermediate series over the $q$-analog Virasoro-like algebra $L$. We first construct four classes of irreducible {\bf Z}-graded $L$-modules of the intermediate series. Then we prove that any {\bf Z}-graded $L$-modules of the intermediate series must be the direct sum of some

H. T. Wong

The report describes the research program on the development of ultra-low-energy germanium detectors, with emphasis on WIMP dark matter searches. A threshold of 100 eV is achieved with a 20 g detector array, providing a unique probe to the low-mas WIMP. Present data at a surface laboratory is expected to give rise to comparable sensitivities with the existin

Alexander Heger, Andrew Cumming, Duncan K. Galloway, Stanford E. Woosley

The X-ray burster GS 1826-24 shows extremely regular Type I X-ray bursts whose energetics and recurrence times agree well with thermonuclear ignition models. We present calculations of sequences of burst lightcurves using multizone models which follow the rp-process nucleosynthesis with an extensive nuclear reaction network. The theoretical and observed burs

Bing-Song Zou, Ju-Jun Xie

The strangeness production in heavy ion collisions was proposed to be probes of the nuclear equation of state, Kaon potential in nuclear medium, strange quark matter and quark-gluon plasma, etc. However, to act as reliable probes, proper understanding of the basic ingredients for the strangeness production, such as $pp \to pK^+Λ$, $pp \to pp ϕ$ and $pp \to n

John Addiss, Jing Cai, Stephen Walley, William Proud

Conventional drop-weight techniques were modified to accommodate low-amplitude force transducer signals from low-strength, cold isostatically pressed 'heavy' composites of polytetrafluoroethylene, aluminum and tungsten. The failure strength, strain and the post-critical behavior of failed samples were measured for samples of different porosity and tu

Nurulla Azamov

In this note, under a certain assumption on an affine space of operators, which admit embedded eigenvalues, it is shown that the singular part of the spectral shift function of any pair of operators from this space is an integer-valued function. The proof uses a natural decomposition of Pushnitski's $μ$-invariant into "absolutely continuous" and

Andrei E. Ghenciu, R. Daniel Mauldin

We present the main concepts and results for Graph Directed Markov Systems that have a finitely irreducible incidence matrix. We then see how these results change when the incidence matrix is not assumed to be finitely irreducible.

C. Torrero, M. Laine, Y. Schroder, F. Di Renzo

Thanks to dimensional reduction, the contributions to the hot QCD pressure coming from so-called soft modes can be studied via an effective three-dimensional theory named Electrostatic QCD (spatial Yang-Mills fields plus an adjoint Higgs scalar). The poor convergence of the perturbative series within EQCD suggests to perform lattice measurements of some of t

Diego Chialva

We provide formulas for the entropy of free-string states depending on their mass, charges and size, both in bosonic and superstring theory (IIA or IIB). We properly define these quantities in full-fledged string theory. We then investigate the corrections to the entropy due to self-interactions of the string for states with fixed mass, charge and size, both

Eric Bedford, Kyounghee Kim, Truong Trung Tuyen, Nina Abarenkova

We compute the degree complexity of a family of birational mappings of the plane with high order singularities.

V. V. Flambaum, W. R. Johnson

Bound muons (also pions, kaons, etc) increase the fission barrier and produce some stabilizing effects for highly charged nuclei. If the binding energy of the muon exceeds $mc^2$, it becomes stable. The $1s$ state of a muon inside an exotic nucleus with atomic number $A= 5Z/2$ and such large charge $Z$ that the $1s$ energy $E$ is in the range $0\le E<-mc^2$

Henry Towsner

Tao has recently proved that if $T_1,...,T_l$ are commuting, invertible, measure-preserving transformations on a dynamical system then for any $L^\infty$ functions $f_1,...,f_l$, the average $\frac{1}{N}\sum_{n=0}^{N-1}\prod_{i\leq l}f_i\circ T^n_i$ converges in the $L^2$ norm. Tao&#39;s proof is unusual in that it translates the problem into a more complica

Hilmar Forkel

We derive and systematically analyze scalar glueball correlation functions in both the hard-wall and dilaton soft-wall approximations to holographic QCD. The dynamical content of the holographic correlators is uncovered by examining their spectral density and by relating them to the operator product expansion, a dilatational low-energy theorem and a recently

N. J. Brassington, G. Fabbiano, D. -W. Kim, A. Zezas

We present the properties of the discrete X-ray sources detected in our monitoring program of the `typical&#39; elliptical galaxy, NGC 3379, observed with Chandra ACIS-S in five separate pointings, resulting in a co-added exposure of 324-ks. From this deep observation, 132 sources have been detected within the region overlapped by all observations, 98 of whi

Niraj Welikala, Andrew J. Connolly, Andrew M. Hopkins, Ryan Scranton

We use the photometric information contained in individual pixels of 44,964 (0.019<z<0.125 and -23.5<M_r<-20.5) galaxies in the Fourth Data Release (DR4) of the Sloan Digital Sky Survey to investigate the effects of environment on galaxy star formation (SF). We use the pixel-z technique, which combines stellar population synthesis models with photometric red

Tobias Goerdt, Ben Moore, Stelios Kazantzidis, Tobias Kaufmann

Ultra compact dwarf galaxies (UCDs) have similar properties as massive globular clusters or the nuclei of nucleated galaxies. Recent observations suggesting a high dark matter content and a steep spatial distribution within groups and clusters provide new clues as to their origins. We perform high-resolution N-body / smoothed particle hydrodynamics simulatio

A. M. Souza, A. Magalhaes, J. Teles, E. R. deAzevedo

In this paper we present an analog of the Bell&#39;s inequalities violation test for $N$ qubits to be performed in a nuclear magnetic resonance (NMR) quantum computer. This can be used to simulate or predict results for different Bell&#39;s inequalities tests, with distinct configurations and larger number of qubits. To demonstrate our scheme, we implemented

Róbert Juhász

We present a real space renormalization group scheme for the problem of random walks in a random environment on a strip, which includes one-dimensional random walk in random environment with bounded non-nearest-neighbor jumps. We show that the model renormalizes to an effective one-dimensional random walk problem with nearest-neighbor jumps and conclude that

Alex G. Dias, C. A. de S. Pires, P. S. Rodrigues da Silva

We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width $Z \to e^+e^-$. Using the precision electroweak data we obtain a strong lower bound $f\geq 5.6$ TeV at 95% C.L. on the characteristic energy scale of the model. It results in a lower bound for the new gauge bosons $W^{\prime\

Matthew Macauley, Henning S. Mortveit

In this paper we study the equivalence relation on the set of acyclic orientations of a graph Y that arises through source-to-sink conversions. This source-to-sink conversion encodes, e.g. conjugation of Coxeter elements of a Coxeter group. We give a direct proof of a recursion for the number of equivalence classes of this relation for an arbitrary graph Y u

Patrick Popescu-Pampu

I have withdrawn the paper, after having incorporated it into the paper arXiv:0712.3484. In the meantime I have discovered that one of the theorems proved in the paper had already been proved by Durfee & Hain.

Philippe Blanchard, Daniel Gandolfo, Lahoussine Laanait, Jean Ruiz

The critical behaviour of the Ising model in the absence of an external magnetic field can be specified either through spontaneous symmetry breaking (thermal criticality) or through cluster percolation (geometric criticality). We extend this to finite external fields for the case of the Potts&#39; model, showing that a geometric analysis leads to the same fi

Kei Fukuda, Akihiko Inoue, Yumiharu Nakano

We present a general approach to the pricing of products in finance and insurance in the multi-period setting. It is a combination of the utility indifference pricing and optimal intertemporal risk allocation. We give a characterization of the optimal intertemporal risk allocation by a first order condition. Applying this result to the exponential utility fu

I. Horn

Evidence is reported for the existence of a parity doublet of Delta resonances with total angular momentum J=3/2 from photoproduction of the p pi^0 eta final state. The two parity partners Delta(1920)P_{33} and Delta(1940)D_{33} make significant contributions to the reaction. Cascades of resonances into Delta(1232) eta, N(1535) pi, and N a_0(980) are clearly

Susmita Chakravorty, Ajit K. Kembhavi, Martin Elvis, Gary Ferland

Understanding the thermal equilibrium (stability) curve may offer insights into the nature of the warm absorbers often found in active galactic nuclei. Its shape is determined by factors like the spectrum of the ionizing continuum and the chemical composition of the gas. We find that the stability curves obtained under the same set of the above mentioned phy

Soumik Pal, Philip Protter

We study strict local martingales via h-transforms, a method which first appeared in Delbaen-Schachermayer. We show that strict local martingales arise whenever there is a consistent family of change of measures where the two measures are not equivalent to one another. Several old and new strict local martingales are identified. We treat examples of diffusio

Ryan Kinser

We define a functor which gives the &#34;global rank of a quiver representation&#34; and prove that it has nice properties which make it a generalization of the rank of a linear map. We demonstrate how to construct other &#34;rank functors&#34; for a quiver Q, which induce ring homomorphisms (called &#34;rank functions&#34;) from the representation ring of Q

Ulrich Bunke, Thomas Schick, Ingo Schroeder, Moritz Wiethaup

The main aim of this paper is the construction of a smooth (sometimes called differential) extension \hat{MU} of the cohomology theory complex cobordism MU, using cycles for \hat{MU}(M) which are essentially proper maps W\to M with a fixed U(n)-structure and U(n)-connection on the (stable) normal bundle of W\to M. Crucial is that this model allows the constr

Hans-Ulrich Stark, Claudio J. Tessone, Frank Schweitzer

For the voter model, we study the effect of a memory-dependent transition rate. We assume that the transition of a spin into the opposite state decreases with the time it has been in its current state. Counter-intuitively, we find that the time to reach a macroscopically ordered state can be accelerated by slowing-down the microscopic dynamics in this way. T

M. Mucha-Kruczynski, O. Tsyplyatyev, A. Grishin, E. McCann

We show theoretically how constant-energy maps of the angle-resolved photoemission intensity can be used to test wave function symmetry in graphene. For monolayer graphene, we demonstrate that the observed anisotropy of ARPES spectra is a manifestation of what has been recently branded as electronic chirality. For bilayer graphene, we show that the anisotrop

Felix Braam, Michael Flossdorf, R. Sekhar Chivukula, Stefano Di Chiara

We propose and discuss the phenomenology of a Topcolor-assisted Technicolor (TC2) model with a flavor-universal hypercharge sector. After discussing the symmetry breaking pattern and low-energy effective Lagrangian, we examine various experimental and theoretical constraints, finding that precision electroweak measurements yield the strongest bounds on the m

T. Ochiai, U. Leonhardt, J. C. Nacher

The aim of an invisibility device is to guide light around any object put inside, being able to hide objects from sight. In this work, we propose a novel design of dielectric invisibility media based on negative refraction and optical conformal mapping that seems to create perfect invisibility. This design has some advantages and more relaxed constraints com

Piotr Jaranowski, Andrzej Królak

The article reviews the statistical theory of signal detection in application to analysis of deterministic gravitational-wave signals in the noise of a detector. Statistical foundations for the theory of signal detection and parameter estimation are presented. Several tools needed for both theoretical evaluation of the optimal data analysis methods and for t

Dongho Chae

We study blow-up rates and the blow-up profiles of possible asymptotically self-similar singularities of the 3D Euler equations, where the sense of convergence and self-similarity are considered in various sense. We extend much further, in particular, the previous nonexistence results of self-similar/asymptotically self-similar singularities obtained in \cit

Jacqueline Chen

We explore the color dependence of the radial profile of satellite galaxies around isolated parent galaxies. Samples of potential satellites selected from large galaxy redshift surveys are significantly contaminated by interlopers -- objects not bound to the parent galaxy. We use the Sloan Digital Sky Survey to estimate the interloper fraction in samples of

Y. Brihaye, Y. Verbin

We find new non-Abelian flux tube solutions in a model of $N_f$ scalar fields in the fundamental representation of SU(N)xU(1) with $N \leq N_f$ (the ``extended non-Abelian Higgs model&#39;&#39;), and study their main properties. Among the solutions there are spinning strings as well as superconducting ones. The solutions exist only in a non trivial domain of

N. Markova, J. Puls

We apply the NLTE atmosphere code FASTWIND to perform a spectroscopic study of a small sample of Galactic B-supergiants from B0 to B9. By means of the resulting data and incorporating additional datasets from alternative studies, we investigate the properties of OB-supergiants and compare our findings with theoretical predictions. As a result we find that du

Oliver C. Schnürer, Abderrahim Azouani, Marc Georgi, Juliette Hell

We consider convex symmetric lens-shaped networks in R^2 that evolve under curve shortening flow. We show that the enclosed convex domain shrinks to a point in finite time. Furthermore, after appropriate rescaling the evolving networks converge to a self-similarly shrinking network, which we prove to be unique in an appropriate class. We also include a class

E. Berti, V. Cardoso, J. A. Gonzalez, U. Sperhake

We present a preliminary study of the multipolar structure of gravitational radiation from spinning black hole binary mergers. We consider three different spinning binary configurations: (1) one &#34;hang-up&#34; run, where the black holes have equal masses and large spins initially aligned with the orbital angular momentum; (2) seven &#34;spin-flip&#34; run

Nathanaël Enriquez, Christophe Sabot, Olivier Zindy

We consider transient one-dimensional random walks in random environment with zero asymptotic speed. An aging phenomenon involving the generalized Arcsine law is proved using the localization of the walk at the foot of &#34;valleys&#34; of height $\log t$. In the quenched setting, we also sharply estimate the distribution of the walk at time $t$.

Paul Federbush

The dimer problem arose in a thermodynamic study of diatomic molecules, and was abstracted into one of the most basic and natural problems in both statistical mechanics and combinatoric mathematics. Given a rectangular lattice of volume V in d dimensions, the dimer problem loosely speaking is to count the number of different ways dimers (dominoes) may be lay

Gesine Reinert, Adrian Röllin

In this paper we establish a multivariate exchangeable pairs approach within the framework of Stein&#39;s method to assess distributional distances to potentially singular multivariate normal distributions. By extending the statistics into a higher-dimensional space, we also propose an embedding method which allows for a normal approximation even when the co