December 2005 arXiv papers — page 33

Ken Williams

This article is intended as a compendium and guide to the variety of Bell Inequality derivations that have appeared in the literature in recent years, classifying them into six broad categories, revealing the underlying, often hidden, assumption common to each - semifactuality. Evaluation of the attendant conditional brings to light a significant EPR loophol

Guilherme da C. P. Innocentini, Jose E. M. Hornos

Intrinsic transcriptional noise induced by operator fluctuations is investigated with a simple spin like stochastic model. The effects of transcriptional fluctuations in protein synthesis is probed by coupling transcription and translation by an amplificative interaction. In the presence of repression a new term contributes to the noise which depends on the

Walton R. Gutierrez

A model is proposed to minimize the total volume of the main distribution networks of fluids in organs such as the kidney and the lung. A consequence of the minimization analysis is that the optimal overall form of the organs is a modified ellipsoid. The variational procedure implementing this minimization is similar to the traditional isoperimetric theorems

D. Kielpinski

We propose a new laser cooling method for atomic species whose level structure makes traditional laser cooling difficult. For instance, laser cooling of hydrogen requires single-frequency vacuum-ultraviolet light, while multielectron atoms need single-frequency light at many widely separated frequencies. These restrictions can be eased by laser cooling on tw

Jeremy Butterfield

This paper forms part of a wider campaign: to deny pointillisme. That is the doctrine that a physical theory's fundamental quantities are defined at points of space or of spacetime, and represent intrinsic properties of such points or point-sized objects located there; so that properties of spatial or spatiotemporal regions and their material contents ar

Jeremy Butterfield

This paper forms part of a wider campaign: to deny pointillisme. That is the doctrine that a physical theory's fundamental quantities are defined at points of space or of spacetime, and represent intrinsic properties of such points or point-sized objects located there; so that properties of spatial or spatiotemporal regions and their material contents ar

V. O. Nesterenko, P. -G. Reinhard, W. Kleinig

Multipole electron modes beyond the Mie plasmon in atomic clusters are investigated within the time-dependent local density approximation theory (TDLDA). We consider the origin of the modes, their connection with basic cluster properties and possible routes of experimental observation. Particular attention is paid to infrared magnetic orbital modes, scissors

V. O. Nesterenko, J. Kvasil, P. -G. Reinhard

We propose a practicable method for describing linear dynamics of different finite Fermi systems. The method is based on a general self-consistent procedure for factorization of the two-body residual interaction. It is relevant for diverse density- and current-dependent functionals and, in fact, represents the self-consistent separable random-phase approxima

S. Kushpil, E. Crescio, P. Giubellino, M. Idzik

The Silicon Drift Detectors will equip two of the six cylindrical layers of high precision position sensitive detectors in the ITS of the ALICE experiment at LHC. In this paper we report the beam test results of a SDD irradiated with 1 GeV electrons. The aim of this test was to verify the radiation tolerance of the device under an electron fluence equivalent

S. I. Bityukov, N. V. Krasnikov, A. Kuznetsov, V. V. Smirnova

As it follows from the interrelation of Gamma and Poisson distributions the observed value of asymmetry for Poisson flows of events has the bias. The Monte Carlo experiment confirms the presence of this bias between the observed and initial asymmetries. The obtained results allow to correct the estimation of the asymmetry of flow rates.

Jung-Wan Ryu, Soo-Young Lee, Chil-Min Kim, Young-Jai Park

We study the optical interaction in a coupled dielectric microdisks by investigating the splitting of resonance positions of interacting whispering gallery modes (WGMs) and their pattern change, depending on the distance between the microdisks. It is shown that the interaction between the WGMs with odd parity about y-axis becomes appreciable at a distance le

Andrzej Nowojewski

A human creates an image basing on the information delivered by photons that arrived at his retina simultaneously. Due to finite and constant velocity of light these photons left the moving body at different times, since not all points of the body are equidistant. In other words its image represents the body as it was in several different times i.e. it is di

A. Di Falco, C. Conti, G. Assanto

By numerically integrating the three-dimensional Maxwell equations in the time domain with reference to a dispersive quadratically nonlinear material, we study second harmonic generation in planar photonic crystal microresonators. The proposed scheme allows efficient coupling of the pump radiation to the defect resonant mode. The out-coupled generated second

Xiao Jianhua

The vorticity plays an important role in aerodynamics and rotational flow. Usually, they are studied with modified Navier-Stokes equation. This research will deduce the motion equation of vorticity from Navier-Stokes equation. To this propose, the velocity gradient field is decomposed as the stack of non-rotation field and pure-rotation field. By introducing

Akira Kageyama, Tooru Sugiyama, Kunihiko Watanabe, Tetsuya Sato

A couple of orthogonal coordinates for dipole geometry are proposed for numerical simulations of plasma geophysics in the Earth's dipole magnetic field. These coordinates have proper metric profiles along field lines in contrast to the standard dipole coordinate system that is commonly used in analytical studies for dipole geometry.

F. M. Nunes, B. Avez, T. Duguet

A study of the effect of deformation and pairing on the development of halo nuclei is presented. Exploratory three-body $core+n+n$ calculations show that both the NN interaction and the deformation/excitation of the core hinder the formation of the halo. Preliminary self-consistent mean-field calculations are used to search for regions in the nuclear chart w

G. K. Nie

In previous work it was shown that the radius of nucleus R is determined by the alpha-cluster structure and can be estimated on the number of alpha-clusters disregarding to the number of excess neutrons. A hypothesis also was made that the radius R_m of a beta-stable isotope, which is actually measured at electron scattering experiments, is determined by the

V. A. Kuz'min, T. V. Tetereva

By analyzing the energy-weighted moments of the strength function calculated in RPA and beyond it is shown that the explanation of the effect of missing strength of Gamow-Teller transitions requires that residual interaction produce high-excited $1^{+}$ particle-hole collective states. The example of this interaction is presented. The manifestations of spin-

J. Iglio, D. V. Shetty, S. J. Yennello, G. A. Souliotis

The symmetry energy and the isoscaling properties of the fragments produced in the multifragmentation of $^{40}$Ar, $^{40}$Ca + $^{58}$Fe, $^{58}$Ni reactions at 25 - 53 MeV/nucleon were investigated within the framework of statistical multifragmentation model. The isoscaling parameters $α$, from the primary (hot) and secondary (cold) fragment yield distribu

A. J. Roberts

Multi-fractal patterns occur widely in nature. In developing new algorithms to determine multi-fractal spectra of experimental data I am lead to the conclusion that generalised dimensions $D_q$ of order $q\leq0$, including the Hausdorff dimension, are effectively \emph{irrelevant}. The reason is that these dimensions are extraordinarily sensitive to regions

Danilo Merlini

We present a calculation involving a function related to the Riemann Zeta function and suggested by two recent works concerning the Riemann Hypothesis: one by Balazard, Saias and Yor and the other by Volchkov. We define an integral m (r) involving the Zeta function in the complex variable s = r + it and find a particurarly interesting expression for m(r) whi

Taeyoung Lee, Amit K. Sanyal, Melvin Leok, N. Harris McClamroch

Attitude estimation is often a prerequisite for control of the attitude or orientation of mechanical systems. Current attitude estimation algorithms use coordinate representations for the group of rigid body orientations. All coordinate representations of the group of orientations have associated problems. While minimal coordinate representations exhibit kin

Anne Schilling

We give a review of the current status of the X=M conjecture. Here X stands for the one-dimensional configuration sum and M for the corresponding fermionic formula. There are three main versions of this conjecture: the unrestricted, the classically restricted and the level-restricted version. We discuss all three versions and illustrate the methods of proof

C. Bruschek, S. Gann, H. Hauser, D. Wagner

Choose a polynomial in three variables with not more than three or four monomials of moderate degree. Take simple coefficients as 1 and -1. Then draw a picture of the solution variety in real three space using a ray-tracing program like POV-Ray, Surf or Spicy. Go to your colleague in the next room, show her/him the picture and ask for a suitable equation. Th

Astrid an Huef, Iain Raeburn, Dana P. Williams

We show that important structural properties of C*-algebras and the multiplicity numbers of representations are preserved under Morita equivalence.

Isabel Hubard, Egon Schulte, Asia Ivic Weiss

This paper presents a technique for constructing new chiral or regular polyhedra (or maps) from self-dual abstract chiral polytopes of rank 4. From improperly self-dual chiral polytopes we derive "Petrie-Coxeter-type" polyhedra (abstract chiral analogues of the classical Petrie-Coxeter polyhedra) and investigate their groups of automorphisms.

Martin Moeller, Eckart Viehweg, Kang Zuo

This survey article discusses some results on the structure of families f:V-->U of n-dimensional manifolds over quasi-projective curves U, with semistable reduction over a compactification Y of U. We improve the Arakelov inequality for the direct images of powers of the dualizing sheaf. For families of Abelian varieties we recall the characterization of Shim

Adrien Dubouloz

Affine surfaces in $\mathbb{C}^{3}$ defined by an equation of the form $x^{n}z-Q(x,y)=0$ have been increasingly studied during the past 15 years. Of particular interest is the fact that they come equipped with an action of the additive group $\mathbb{C}_{+}$ induced by such an action on the ambient space. The litterature of the last decade may lead one to be

Dipendra Prasad

{We use the recent proof of Jacquet's conjecture due to Harris and Kudla, and the Burger-Sarnak principle to give a proof about the relationship between the existence of trilinear forms on representations of $GL_2(k_u)$ for a non-Archimedean local field $k_u$ and local epsilon factors which was earlier proved only in the odd residue characteristic by thi

Bartosz Zielinski

The paper introduces the notion of a locally coalgebra-Galois extension and, as its special case, a locally cleft extension. The necessary and sufficient conditions for a locally coalgebra-Galois extension to be a (global) coalgebra-Galois extension are stated. As an important special case, it is proven, that under not very restrictive conditions the gluing

Frederic Robert

We let $Ω$ be a smooth bounded domain of $\mathbb{R}^4$ and a sequence of fonctions $(V_k)_{k\in\mathbb{N}}\in C^0(Ω)$ such that $\lim_{k\to +\infty}V_k=1$ in $C^0_{loc}(Ω)$. We consider a sequence of functions $(u_k)_{k\in\mathbb{N}}\in C^4(Ω)$ such that $$Δ^2 u_k=V_k e^{4u_k}$$ in $Ω$ for all $k\in\mathbb{N}$. We address in this paper the question of the a

Frederic Robert

We investigate the asymptotic behavior as $k \to +\infty$ of sequences $(u_k)_{k\in\mathbb{N}}\in C^4(Ω)$ of solutions of the equations $Δ^2 u_k=V_k e^{4u_k}$ on $Ω$, where $Ω$ is a bounded domain of $\mathbb{R}^4$ and $\lim_{k\to +\infty}V_k=1$ in $C^0_{loc}(Ω)$. The corresponding 2-dimensional problem was studied by Brézis-Merle and Li-Shafrir who pointed

Luis Fuentes Garcia

We give a bound for the multiple Seshadri constants on surfaces with Picard number 1. The result is a natural extension of the bound of A. Steffens for simple Seshadri constants. In particular, we prove that the Seshadri constant $ε(L; r)$ is maximal when $rL^2$ is a square.

Fabrice Blache

In a preceding article, we have studied a generalization of the problem of finding a martingale on a manifold whose terminal value is known. This article completes the results obtained in the first article by providing uniqueness and existence theorems in a general framework (in particular if positive curvatures are allowed), still using differential geometr

He Chen, Xueliang Li

Let $G$ be an edge-colored graph. A heterochromatic (rainbow, or multicolored) path of $G$ is such a path in which no two edges have the same color. Let $d^c(v)$ denote the color degree and $CN(v)$ denote the color neighborhood of a vertex $v$ of $G$. In a previous paper, we showed that if $d^c(v)\geq k$ (color degree condition) for every vertex $v$ of $G$,

Yoichi Motohashi

Prime numbers or primes are man's eternal treasures that have been cherished for several millennia, until today. As their academic ancestors in ancient Mesopotamia, many mathematicians are still trying hard to see primes better. I shall relate here a part of my impressions that I have gathered in a corner of my mind through my own research and excursions

C. Galindo, F. Monserrat

We give an algorithm to decide whether an algebraic plane foliation F has a rational first integral and to compute it in the affirmative case. The algorithm runs whenever we assume the polyhedrality of the cone of curves of the surface obtained after blowing-up the set B_F of infinitely near points needed to get the dicritical exceptional divisors of a minim

Emmanuel Candes, Justin Romberg, Terence Tao

Suppose we wish to recover an n-dimensional real-valued vector x_0 (e.g. a digital signal or image) from incomplete and contaminated observations y = A x_0 + e; A is a n by m matrix with far fewer rows than columns (n << m) and e is an error term. Is it possible to recover x_0 accurately based on the data y? To recover x_0, we consider the solution x* to the

Günter M. Ziegler

These lecture notes treat some current aspects of two closely interrelated topics from the theory of convex polytopes: the shapes of f-vectors, and extremal constructions. The first lecture treats 3-dimensional polytopes; it includes a complete proof of the Koebe--Andreev--Thurston theorem, using the variational principle by Bobenko & Springborn (2004). In L

Panki Kim

We give a probabilistic proof of relative Fatou&#39;s theorem for $(-Δ)^{α/2}$-harmonic functions (equivalently for symmetric $α$-stable processes) in bounded $κ$-fat open set where $α\in (0,2)$. That is, if $u$ is positive $(-Δ)^{α/2}$-harmonic function in a bounded $κ$-fat open set $D$ and $h$ is singular positive $(-Δ)^{α/2}$-harmonic function in $D$, the

Leonardo Mondaini, E. C. Marino

We obtain an exact asymptotic expression for the two-point fermion correlation functions in the massive Thirring model (MTM) and show that, for $β^2=8π$, they reproduce the exactly known corresponding functions of the massless theory, explicitly confirming the irrelevance of the mass term at this point. This result is obtained by using the Coulomb gas repres

L. Hlavaty, M. Turek

Riemannian coordinates for flat metrics corresponding to three--dimensional conformal Poisson--Lie T--dualizable sigma models are found by solving partial differential equations that follow from the transformations of the connection components. They are then used for finding general forms of the dilaton fields satisfying the vanishing beta equations of the s

M. L. Grigoryan

The radiation from a relativistic electron uniformly rotating along an orbit in the equatorial plane of a dielectric ball was calculated taking into account the dielectric losses of energy and dispersion of electromagnetic oscillations inside the substance of ball. It was shown that due to the presence of ball the radiation from the particle at some harmonic

K. Zarembo

The spectrum of operators in the su(2) sector of N=4 SYM is bounded because the number of operators is finite. According to the AdS/CFT correspondence, the string spectrum in this sector should be also bounded. In this paper the upper bound on the scaling dimension is calculated in the limit of the large R-charge using Bethe ansatz.

Robert Brandenberger, Natalia Shuhmaher

We propose a mechanism for solving the horizon and entropy problems of standard cosmology which does not make use of cosmological inflation. Crucial ingredients of our scenario are brane gases, extra dimensions, and a confining potential due to string gas effects which becomes dominant at string-scale brane separations. The initial conditions are taken to be

Naoki Sasakura

A dynamical fuzzy space might be described in terms of a dynamical three-index variable C_{ab}^c, which determines the algebraic relations f_a f_b =C_{ab}^c f_c of the functions f_a on a fuzzy space. A fuzzy analogue of the general coordinate transformation would be given by the general linear transformation on f_a. The solutions to the invariant equations o

Piotr Kosinski, Pawel Maslanka

Simple argument in favour of unitarity, to all orders, of space-like noncommutative theory is given.

Ricardo Fariello, Hilmar Forkel, Gastao Krein

We identify and analyze quasiperiodic and chaotic motion patterns in the time evolution of a classical, non-Abelian Bogomol&#39;nyi-Prasad-Sommerfield (BPS) dyon pair at low energies. This system is amenable to the geodesic approximation which restricts the underlying SU(2) Yang-Mills-Higgs dynamics to an eight-dimensional phase space. We numerically calcula

Z. Chacko, Hock-Seng Goh, Roni Harnik

We present twin Higgs models based on the extension of the Standard Model to left-right symmetry that protect the weak scale against radiative corrections up to scales of order 5 TeV. In the ultra-violet the Higgs sector of these theories respects an approximate global symmetry, in addition to the discrete parity symmetry characteristic of left-right symmetr

P. Colangelo, F. De Fazio, R. Ferrandes, A. Ozpineci

We discuss the structure of the narrow mesons with charm and strangeness $D_{sJ}^*(2317)$ and $D_{sJ}(2460)$, stressing the role of the radiative decay modes in shedding light on the quark content of these states. We argue that present experimental data favour the interpretation of the two states as ordinary $\bar c s$ mesons. We suggest the existence of res

L. Maiani, F. Piccinini, A. D. Polosa, V. Riquer

The 4-quark interpretation of the recently discovered X(3872) and Y(4260) resonances is briefly discussed.

Bohdan Grzadkowski, Jose Wudka

We consider general five-dimensional gauge theories compactified on on an orbifold S1/Z2 with all fields propagating in the bulk. We propose a generalized set of boundary conditions and derive the general features of the low energy-spectrum. The results are illustrated with two simple examples.

H. Stüben, S. Wollny

In the framework of I3HP there are two Transnational Access Activities related to Computational Hadron Physics. One of these activities is access to the mass storage system at Konrad-Zuse-Zentrum fuer Informationstechnik Berlin (ZIB). European lattice physics collaborations can apply for mass storage capacity in order to store and share their configurations

Stefan Westerhoff

One of the most striking astrophysical phenomena today is the existence of cosmic ray particles with energies in excess of 10^20 eV. While their presence has been confirmed by a number of experiments, it is not clear where and how these particles are accelerated to these energies and how they travel astronomical distances without substantial energy loss. We

H1 Collaboration

Deep-inelastic ep scattering data taken with the H1 detector at HERA and corresponding to an integrated luminosity of 106 pb^{-1} are used to study the differential distributions of event shape variables. These include thrust, jet broadening, jet mass and the C-parameter. The four-momentum transfer Q is taken to be the relevant energy scale and ranges betwee

Daniele Oriti

We give a very brief introduction to the group field theory approach to quantum gravity, a generalisation of matrix models for 2-dimensional quantum gravity to higher dimension, that has emerged recently from research in spin foam models.

P. Diaz, M. A. Per, A. Segui

We address the initial conditions for an expanding cosmology using the holographic principle. For the case of a closed model, the old prescription of Fishler and Susskind, that uses the particle horizon to encode the bulk degrees of freedom, can be implemented for accelerated models with enough acceleration. As a bonus we have singularity free bouncing model

Abhas Mitra

In a recent preprint, gr-qc/0511123, Dadhich has given a brief yet beautiful exposition on some of the research works by Prof. A.K. Raychaudhuri. Here Dadhich highlights the fact that the apparently ``self-evident&#39;&#39; assumption of occurrence of ``trapped surfaces&#39;&#39; may not be realized atleast in some specific cosmological models though no gene

Petros Elia, P. Vijay Kumar

In this work we explicitly provide the first ever optimal, with respect to the Zheng-Tse diversity multiplexing gain (D-MG) tradeoff, cooperative diversity schemes for wireless relay networks. The schemes are based on variants of perfect space-time codes and are optimal for any number of users and all statistically symmetric (and in some cases, asymmetric) f

I. Josopait

I will present my implementation &#39;n-units&#39; of physical units into C++ programs. It allows the compiler to check for dimensional consistency.

Lane A. Hemaspaandra, Leen Torenvliet

We prove that P-sel, the class of all P-selective sets, is EXP-immune, but is not EXP/1-immune. That is, we prove that some infinite P-selective set has no infinite EXP-time subset, but we also prove that every infinite P-selective set has some infinite subset in EXP/1. Informally put, the immunity of P-sel is so fragile that it is pierced by a single bit of

Emmanuel Trizac, Gabriel Tellez

Making use of results pertaining to Painleve III type equations, we revisit the celebrated Onsager-Manning-Oosawa condensation phenomenon for charged stiff linear polymers, in the mean-field approximation with salt. We obtain analytically the associated critical line charge density, and show that it is severely affected by finite salt effects, whereas previo

J. A. Gascon, H. M. Pastawski

In metallic nanoparticles, shifts in the ionization energy of surface atoms with respect to bulk atoms can lead to surface bands. Within a simple Tight Binding model we find that the projection of the electronic density of states on these sites presents two overlapping structures. One of them is characterized by the level spacing coming from bulk states and

L. V. Pourovskii, M. I. Katsnelson, A. I. Lichtenstein

We report on results of the first realistic electronic structure calculations of the Pu-based PuCoGa5 superconductor based on the dynamical mean field theory. We find that dynamical correlations due to the local Coulomb interaction between Pu f-electrons lead to substantial modification of the electronic structure with a narrow peak being formed in vicinity

Matthieu Wyart

We poorly understand the properties of amorphous systems at small length scales, where a continuous elastic description breaks down. This is apparent when one considers their vibrational and transport properties, or the way forces propagate in these solids. Little is known about the microscopic cause of their rigidity. Recently it has been observed numerical

L. Szunyogh, G. Zarand, S. Gallego, M. C. Munoz

We propose a new mechanism for surface-induced magnetic anisotropy to explain the thickness-dependence of the Kondo resistivity of thin films of dilute magnetic alloys. The surface anisotropy energy, generated by spin-orbit coupling on the magnetic impurity itself, is an oscillating function of the distance d from the surface and decays as 1/d^2. Numerical e

Marcin Kostur, Lukasz Machura, Peter Hänggi, Jurek Luczka

The noise-assisted, directed transport in a one-dimensional dissipative, inertial Brownian motor of the rocking type that is exposed to an external bias is investigated. We demonstrate that the velocity-load characteristics is distinctly non-monotonic, possessing regimes with a {\em negative differential mobility}. In addition, we evaluate several possible e

M. P. Singh, W. Prellier, L. Mechin, Ch. Simon

Superlattices composed of ferromagnetics, namely La$_{0.7}$Ca$_{0.3}$MnO$_3$ (LCMO), and ferroelectrics, namely, BaTiO$_3$(BTO) were grown on SrTiO$_3$ at 720$^o$C by pulsed laser deposition process. While the out-of-plane lattice parameters of the superlattices, as extracted from the X-ray diffraction studies, were found to be dependent on the BTO layer thi

Maria D&#39;Orsogna, Tom Chou

We model the kinetics of ligand-receptor systems, where multiple ligands may bind and unbind to the receptor, either randomly or in a specific order. Equilibrium occupation and first occurrence of complete filling of the receptor are determined and compared. At equilibrium, receptors that bind ligands sequentially are more likely to be saturated than those t

J. J. Xiao, K. Yakubo, K. W. Yu

We have identified a new type of transition from extended to localized vibrational states in one-dimensional graded elastic chains of coupled harmonic oscillators, in which the vibrating masses or nearest-coupling force constants vary linearly along the chain. We found that the delocalization transition occurs at the maximum frequency of the corresponding ho

John Schliemann, Daniel Loss, R. M. Westervelt

The notion of zitterbewegung is a long-standing prediction of relativistic quantum mechanics. Here we extend earlier theoretical studies on this phenomenon for the case of III-V zinc-blende semiconductors which exhibit particularly strong spin-orbit coupling. This property makes nanostructures made of these materials very favorable systems for possible exper

Eva G. Noya, Jonathan P. K. Doye

The thermal behaviour of the 309-atom Lennard-Jones cluster, whose structure is a complete Mackay icosahedron, has been studied by parallel tempering Monte Carlo simulations. Surprisingly for a magic number cluster, the heat capacity shows a very pronounced peak before melting, which is attributed to several coincident structural transformation processes. Th

N. S. Tonchev

We present analytical results for the finite-size scaling in d--dimensional O(N) systems with strong anisotropy where the critical exponents (e.g. ν_{||} and ν_{\perp}) depend on the direction. Prominent examples are systems with long-range interactions, decaying with the interparticle distance r as r^{-d-σ} with different exponents σin corresponding spatial

Zhongzhi Zhang, Lili Rong

In a recursive way and by including a parameter, we introduce a family of deterministic scale-free networks. The resulting networks exhibit small-world effects. We calculate the exact results for the degree exponent, the clustering coefficient and the diameter. The major points of our results indicate: the degree exponent can be adjusted; the clustering coef

K. Noda, M. Akaki, T. Kikuchi, D. Akahoshi

We have investigated the dielectric and magnetic properties of Eu$_{0.595}$Y$_{0.405}$MnO$_{3}$ $without$ the presence of the 4$f$ magnetic moments of the rare earth ions, and have found two ferroelectric phases with polarization along the $a$ and $c$ axes in a zero magnetic field. A magnetic field induced switching from one to the other ferroelectric phase

M. Strange, K. S. Thygesen, K. W. Jacobsen

We have performed first-principles calculations for the mechanic and electric properties of pure Pt nano-contacts and a Pt contact with a single CO molecule adsorbed. For the pure Pt contacts we see a clear difference between point contacts and short chains in good agreement with experiments. We identify a tilted bridge configuration for the Pt-CO-Pt contact

Bikas K Chakrabarti, Arnab Chatterjee

We introduce here the two-fractal model of earthquake dynamics. As the fractured surfaces have self-affine properties, we consider the solid-solid interface of the earth&#39;s crust and the tectonic plate below as fractal surfaces. The overlap or contact area between the two surfaces give a measure of the stored elastic energy released during a slip. The ove

Xifan Wu, David Vanderbilt

While electrical compatibility constraints normally prevent head-to-head (HH) and tail-to-tail (TT) domain walls from forming in ferroelectric materials, we propose that such domain walls could be stabilized by intentional growth of atomic layers in which the cations are substituted from a neighboring column of the periodic table. In particular, we carry out

W. Montfrooij, M. C. Aronson, B. D. Rainford, J. A. Mydosh

We present inelastic neutron scattering measurements on the intermetallic compounds Ce(Ru$_{1-x}$Fe$_x$)$_2$Ge$_2$ ($x$=0.65, 0.76 and 0.87). These compounds represent samples in a magnetically ordered phase, at a quantum critical point and in the heavy-fermion phase, respectively. We show that at high temperatures the three compositions have the identical r

Chien-Hsun Chen

We propose a model that leads to the formation of non-equilibrium finite-size domains in a biological membrane. Our model considers the active conformational change of the inclusions and the coupling between inclusion density and membrane curvature. Two special cases with different interactions are studied by Monte Carlo simulations. In case (i) exited state

L. Son, R. Ryltcev

Liquids with quasi - chemical bonding between molecules are described in terms of vertex model. It is shown that this bonding results in liquid - liquid phase transition, which occurs between phases with different mean density of intermolecular bonds. The transition may be suggested to be a universal phenomena for those liquids.

M. Bonitz, V. S. Filinov, V. E. Fortov, P. R. Levashov

The analysis of Coulomb crystallization is extended from one-component to two-component plasmas. Critical parameters for the existence of Coulomb crystals are derived for both classical and quantum crystals. In the latter case, a critical mass ratio of the two charged components is found which is of the order of 80. Thus, holes in semiconductors with suffici

Marcos Rigol

We present an exact study of the finite-temperature properties of hard-core bosons (HCB&#39;s) confined on one-dimensional optical lattices. Our solution of the HCB problem is based on the Jordan-Wigner transformation and properties of Slater determinants. We analyze the effects of the temperature on the behavior of the one-particle correlations, the momentu

Chaohong Lee, Joachim Brand

Matter-wave bright solitons are predicted to reflect from a purely attractive potential well although they are macroscopic objects with classical particle-like properties. The non-classical reflection occurs at small velocities and a pronounced switching to almost perfect transmission above a critical velocity is found, caused by nonlinear mean-field interac

M. Rosvall, A. Gronlund, P. Minnhagen, K. Sneppen

We investigate the searchability of complex systems in terms of their interconnectedness. Associating searchability with the number and size of branch points along the paths between the nodes, we find that scale-free networks are relatively difficult to search, and thus that the abundance of scale-free networks in nature and society may reflect an attempt to

Sofian Teber

Translocation properties of ionic channels are investigated, on the basis of classical electrostatics, with an emphasis on asymptotic formulas for the potential and field associated with a point charge in the channel. Due to image charges in the membrane, we show that ions in an infinite length channel interact via a one-dimensional (1D) Coulomb potential. T

M. Rosvall, P. Minnhagen, K. Sneppen

We study navigation with limited information in networks and demonstrate that many real-world networks have a structure which can be described as favoring communication at short distance at the cost of constraining communication at long distance. This feature, which is robust and more evident with limited than with complete information, reflects both topolog

Shrivalli N. Bhat, Ajay Sharma, S. V. Bhat

Three long standing problems related to the physics of water viz, the possibility of vitrifying bulk water by rapid quenching, its glass transition, and the supposed impossibility of obtaining supercooled water between 150 and 233 K, the so-called &#39;no man&#39;s land&#39;of its phase diagram, are studied using the highly sensitive technique of spin probe

David M. Russell, Sara L. Ellison, Chris R. Benn

We present a sample of 33 damped Lyman alpha systems (DLAs) discovered in the Sloan Digital Sky Survey (SDSS) whose absorption redshifts (z_abs) are within 6000 km/s of the QSO&#39;s systemic redshift (z_sys). Our sample is based on 731 2.5 < z_sys < 4.5 non-broad-absorption-line (non-BAL) QSOs from Data Release 3 (DR3) of the SDSS. We estimate that our sear

Tepedelenlioglu Emre, Ogelman Hakki

PSR B0355+54 is one of the handful of pulsars that has been observed with both Chandra and XMM-Newton. The analysis of the archival data has revealed the pulsar and a ~30 arcsec compact nebula surrounding it. XMM-Newton also has detected a trail which extends ~6 arcmin and similar to the compact nebula is also counter-aligned with the proper motion of the pu

Christopher J. Burke, B. Scott Gaudi, D. L. DePoy, Richard W. Pogge

We analyze a 19-night photometric search for transiting extrasolar planets in the open cluster NGC 1245. An automated transit search algorithm with quantitative selection criteria finds six transit candidates; none are bona fide planetary transits. We characterize the survey detection probability via Monte Carlo injection and recovery of realistic limb-darke

Lynn D. Matthews, Margarita Karovska

We report the first spatially resolved radio continuum measurements of the Mira AB symbiotic binary system, based on observations obtained with the Very Large Array (VLA). This is the first time that a symbiotic binary has been resolved unambiguously at centimeter wavelengths. We describe the results of VLA monitoring of both stars over a ten month period, t

X. Z. Zheng, E. F. Bell, H. -W. Rix, C. Papovich

We stack Spitzer 24 micron images for ~7000 galaxies with 0.1<z<1 in the Chandra Deep Field South to probe the thermal dust emission in low-luminosity galaxies over this redshift range. Through stacking, we can detect mean 24 micron fluxes that are more than an order of magnitude below the individual detection limit. We find that the correlations for low and

R. E. Mason, T. R. Geballe, C. Packham, N. A. Levenson

We present spatially-resolved, near-diffraction-limited 10 micron spectra of the nucleus of the Seyfert 2 galaxy NGC 1068, obtained with Michelle, the mid-IR imager and spectrometer on the 8.1 m Gemini North telescope. The spectra cover the nucleus and the central 6.0&#34; x 0.4&#34; of the ionization cones at a spatial resolution of approximately 0.4&#34; (

Gert Huetsi

We calculate the redshift-space power spectrum of the Sloan Digital Sky Survey (SDSS) Data Release 4 (DR4) Luminous Red Galaxy (LRG) sample, finding evidence for a full series of acoustic features down to the scales of \sim 0.2 hMpc^{-1}. This corresponds up to the 7th peak in the CMB angular power spectrum. The acoustic scale derived, (105.4 \pm 2.3) h^{-1}

Davor Krajnovic, Michele Cappellari, P. Tim de Zeeuw, Yannick Copin

We present a generalisation of surface photometry to the higher-order moments of the line-of-sight velocity distribution of galaxies observed with integral-field spectrographs. The generalisation follows the approach of surface photometry by determining the best fitting ellipses along which the profiles of the moments can be extracted and analysed by means o

Fabio De Colle, Alejandro Raga

We study the H$α$ emission from jets using two-dimensional axisymmetrical simulations. We compare the emission obtained from hydrodynamic (HD) simulations with that obtained from magnetohydrodynamics (MHD) simulations. The magnetic field is supposed to be present in the jet only, and with a toroidal configuration. The simulations have time-dependent ejection

B. J. Mochejska, K. Z. Stanek, D. D. Sasselov, A. H. Szentgyorgyi

We have undertaken a long-term project, Planets in Stellar Clusters Extensive Search (PISCES), to search for transiting planets in open clusters. In this paper we present the results for NGC 2158, an intermediate age, populous cluster. We have monitored the cluster for over 260 hours, spread over 59 nights. We have detected one candidate transiting low lumin

D. Bazeia, C. B. Gomes, L. Losano, R. Menezes

This work deals with cosmological models driven by real scalar field, described by standard dynamics in generic spherical, flat, and hyperbolic geometries. We introduce a first-order formalism, which shows how to relate the potential that specifies the scalar field model to Hubble&#39;s parameter in a simple and direct manner. Extensions to tachyonic dynamic

Christian T. Byrnes, David Wands

Vacuum fluctuations in the inflaton field driving chaotic inflation with a quadratic potential give a red spectrum of primordial density perturbations, n=0.97. However angular fluctuations in an O(N)-symmetric quadratic potential have a very nearly scale-invariant spectrum, n=0.9998. We investigate the possibility that these isocurvature field perturbations