arXiv papers from December 2007

Chao-Xing Liu, Bin Zhou, Shun-Qing Shen, Bang-fen Zhu

We investigate the current-induced spin polarization in the two-dimensional hole gas (2DHG) with the structure inversion asymmetry. By using the perturbation theory, we re-derive the effective $k$-cubic Rashba Hamiltonian for 2DHG and the generalized spin operators accordingly. Then based on the linear response theory we calculate the current-induced spin po

Reinhard Laubenbacher, Brandilyn Stigler

Design of experiments is a branch of statistics that aims to identify efficient procedures for planning experiments in order to optimize knowledge discovery. Network inference is a subfield of systems biology devoted to the identification of biochemical networks from experimental data. Common to both areas of research is their focus on the maximization of in

Greg J. Stephens, William Bialek

We consider words as a network of interacting letters, and approximate the probability distribution of states taken on by this network. Despite the intuition that the rules of English spelling are highly combinatorial (and arbitrary), we find that maximum entropy models consistent with pairwise correlations among letters provide a surprisingly good approxima

Xiao-Liang Qi, Shou-Cheng Zhang

The quantum spin Hall state is a topologically non-trivial insulator state protected by the time reversal symmetry. We show that such a state always leads to spin-charge separation in the presence of a $\pi$ flux. Our result is generally valid for any interacting system. We present a proposal to experimentally observe the phenomenon of spin-charge separation

Reinhard Laubenbacher, Abdul S. Jarrah, Henning Mortveit, S. S. Ravi

Many complex systems can be modeled as multiagent systems in which the constituent entities (agents) interact with each other. The global dynamics of such a system is determined by the nature of the local interactions among the agents. Since it is difficult to formally analyze complex multiagent systems, they are often studied through computer simulations. W

B. Z. Kopeliovich, H. -J. Pirner, I. K. Potashnikova, Ivan Schmidt

The Berger model of perturbative fragmentation of quarks to pions is improved by providing an absolute normalization and keeping all terms in a (1-z) expansion, which makes the calculation valid at all values of fractional pion momentum z. We also replace the nonrelativistic wave function of a loosely bound pion by the more realistic procedure of projecting

A. K. Vidybida

Based on numerical simulation of Hodgkin and Huxley type neuron stimulated from many synaptic inputs, an abstract concept of signal processing in individual neuron is proposed. In the concept proposed, neuron performs binding of synaptic inputs into a single output event, based on the degree of temporal coherence between the inputs. Inhibition serves as cont

Don N. Page

Modern science developed within a culture of Judeo-Christian theism, and science and theism have generally supported each other. However, there are certainly areas in both science and religion that puzzle me. Here I outline some puzzles that have arisen for me concerning everlasting life, human free will, divine free will, the simplicity and probability of G

Don N. Page

Scientists have measured that what we can see of space is about a billion billion billion billion billion billion billion billion billion (10^81) times the volume of an average human. Inflationary theory suggests that the entirety of space is vastly larger. Quantum theory suggests that there are very many different copies of space of the same basic kind as o

Mu-Chun Chen, D. R. Timothy Jones, Arvind Rajaraman, Hai-Bo Yu

We present a realistic supersymmetric SU(5) model combined with a non-anomalous U(1)_F symmetry. We find a set of U(1)_F charges which automatically lead to the realistic mass hierarchy and mixing patterns for quarks, leptons and neutrinos. All gauge anomalies, including the [U(1)_F]^3 anomaly, are cancelled in our model without invoking the Green-Schwarz me

M. Vestergaard, X. Fan, C. A. Tremonti, Patrick S. Osmer

We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3 <= z <= 5 for a well-defined, homogeneous sample of 15,180 quasars from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3) within an effective area of 1644 square degrees. This sample is the most uniform statistically significant subset available for

B. R. Zeiger, W. F. Brisken, S. Chatterjee, W. M. Goss

Over the last decade, considerable effort has been made to measure the proper motions of the pulsars B1757-24 and B1951+32 in order to establish or refute associations with nearby supernova remnants and to understand better the complicated geometries of their surrounding nebulae. We present proper motion measurements of both pulsars with the Very Large Array

Natalia M. Litchinitser, Andrei I. Maimistov, Ildar R. Gabitov, Roald Z. Sagdeev

Electromagnetic field propagation through a transition layer between the positive-index and negative-index materials with linearly changing dielectric permittivity and magnetic permeability was investigated. It is shown that at oblique incidence, the components of both TE- and TM-waves exhibit singular behavior in the vicinity of the point where both dielect

Victor Kurasov

The perturbative theory of the nucleation kinetics is analyzed. A new improvement is suggested and compared with numerical calculations.

Roman Sverdlov, Luca Bombelli

The goal of this paper is to propose an approach to the formulation of dynamics for causal sets and coupled matter fields. We start from the continuum version of the action for a Klein-Gordon field coupled to gravity, and rewrite it first using quantities that have a direct correspondent in the case of a causal set, namely volumes, causal relations, and time

Victor Kurasov

The late stages of the nucleation have been described analytically. The approximate solution of the Zel'dowich-Folmer-Frenkel equation has been constructed.

J. W. Alldredge, Jinho Lee, K. McElroy, M. Wang

A complete knowledge of its excitation spectrum could greatly benefit efforts to understand the unusual form of superconductivity occurring in the lightly hole-doped copper-oxides. Here we use tunnelling spectroscopy to measure the T\to 0 spectrum of electronic excitations N(E) over a wide range of hole-density p in superconducting Bi_{2}Sr_{2}CaCu_{2}O_{8+/

S. G. Rajeev

We solve exactly the classical non-relativistic Landau-Lifshitz equations of motion for a charged particle moving in a Coulomb potential, including radiation damping. The general solution involves the Painleve transcendent of type II. It confirms our physical intuition that a negatively charged classical particle will spiral into the nucleus, supporting the

Stephen P. Martin

If the lighter top squark has no kinematically allowed two-body decays that conserve flavor, then it will form hadronic bound states. This is required in models that are motivated by the supersymmetric little hierarchy problem and obtain the correct thermal relic abundance of dark matter by top-squark-mediated neutralino annihilations, or by top-squark-neutr

Gregg Jaeger, Kevin Ann

We demonstrate that multipartite Bell-inequality violations can be fully destroyed in finite time in three-qubit systems subject only to the mechanism of local external asymptotic dephasing noise. This broadens the study of local-noise-induced sudden death of nonlocal behavior, extending it beyond the realm of bipartite systems, to which it had previously be

V. Kreiman

The product of any finite number of factorial Schur functions can be expanded as a $Z[y]$-linear combination of Schur functions. We give a rule for computing the coefficients in such an expansion which generalizes a specialization of the Molev-Sagan rule, which in turn generalizes the classical Littlewood-Richardson rule.

Orlando Alvarez, Blazej Ruszczycki

We generalize previous results on target space duality to the case where there are background fields and the sigma model lagrangian has a potential function.

Orlando Alvarez, Blazej Ruszczycki

Classical target space duality transformations are studied for the non-linear sigma model with a dilaton field. Working within the framework of the Hamiltonian formalism we require the duality transformation to be a property only of the target spaces. We obtain a set of restrictions on the geometrical data.

Patrizio Frosini

Contradiction is often seen as a defect of intelligent systems and a dangerous limitation on efficiency. In this paper we raise the question of whether, on the contrary, it could be considered a key tool in increasing intelligence in biological structures. A possible way of answering this question in a mathematical context is shown, formulating a proposition

Jae Ho Heo, Wai-Yee Keung

An appended sector of two octet-colored scalars, each an electroweak doublet, is an interesting extension of the simple two Higgs doublet model motivated by the minimal flavor violation. Their rich CP violating interaction gives rise to a sizable electron electric dipole moment, besides the quark electric dipole moment via the two-loop contribution of Barr-Z

Fang Chen, James M. Cline, Sugumi Kanno

We study the Friedmann equation for the warped codimension-two braneworld background which most closely resembles the Randall-Sundrum model. Extra matter on the (Planck) 4-brane, with equation of state p_\theta=(\alpha-1)\rho for the azimuthal pressure, is required to satisfy the junction conditions. For 1 < \alpha < 5, we show that there are two static solu

Saptarshi Mandal, Naveen Surendran

We introduce a spin-1/2 model in three dimensions which is a generalization of the well-known Kitaev model on a honeycomb lattice. Following Kitaev, we solve the model exactly by mapping it to a theory of non-interacting fermions in the background of a static Z_2 gauge field. The phase diagram consists of a gapped phase and a gapless one, similar to the two-

Gregory Gabadadze, Rachel A. Rosen

A relativistic system of electrically charged fermions and oppositely charged massive scalars with no self-interactions, is argued to have a long-lived collective state with a net charge. The charge is residing near the surface of the spherically-symmetric state, while the interior consists of the condensed scalars, that are neutralized by the fermions. The

Dawood A. Kothawala, S. Shankaranarayanan, L. Sriramkumar

Modes emerging out of a collapsing black hole are red-shifted to such an extent that Hawking radiation at future null infinity consists of modes that have energies beyond the Planck scale at past null infinity. This indicates that physics at the Planck scale may modify the spectrum of Hawking radiation and the associated stress-energy tensor of the quantum f

K K Szabo

The thesis will present results in Quantum Chromo Dynamics (QCD) with dynamical lattice fermions. The topological susceptibilty in QCD is determined, the calculations are carried out with dynamical overlap fermions. The most important properties of the quark-gluon plasma phase of QCD are studied, for which dynamical staggered fermions are used.

Axel Krause

We discuss vacuum energy in string and M-theory with a focus on heterotic M-theory. In the latter theory a mechanism is described for maintaining zero vacuum energy after supersymmetry breaking. Higher-order corrections can be expected to give a sufficiently small amount of vacuum energy to possibly account for dark energy.

Simon Gravel, Veit Elser

Many difficult computational problems involve the simultaneous satisfaction of multiple constraints which are individually easy to satisfy. Such problems occur in diffractive imaging, protein folding, constrained optimization (e.g., spin glasses), and satisfiability testing. We present a simple geometric framework to express and solve such problems and apply

Maryam Modjaz, R. P. Kirshner, S. Blondin, P. Challis

Double-peaked oxygen lines in the nebular spectra of two peculiar Type Ib/c Supernovae (SN Ib/c) have been interpreted as off-axis views of a GRB-jet or unipolar blob ejections. Here we present late-time spectra of 8 SN IIb, Ib and Ic and show that this phenomenon is common and should not be so firmly linked to extraordinary explosion physics. The line profi

PHENIX Collaboration, A. Adare

Yields for J/psi production in Cu+Cu collisions at sqrt (s_NN)= 200 GeV have been measured by the PHENIX experiment over the rapidity range |y| < 2.2 at transverse momenta from 0 to beyond 5 GeV/c. The invariant yield is obtained as a function of rapidity, transverse momentum and collision centrality, and compared with results in p+p and Au+Au collisions at

C. Bouzar, T. Saidi

The well-known characterizations of Schwartz space $\mathcal{S}$ of rapidly decreasing functions is extended to the algebra $\mathcal{G}_{\mathcal{S}}$ of rapidly decreasing generalized functions and to the algebra $\mathcal{G}_{% \mathcal{S}}^{\infty}$ of regular rapidly decreasing generalized functions.

I. Y. Park

We analyze one loop scattering amplitudes of the massless states on a stack of D3-branes. We use the vertex operators that have been obtained in the direct open string analysis developed in arXiv:0708.3452. The method does not have the obstacle of the D9 computation which is associated with the appearance of an $\e$-tensor. The divergence structure is not th

Charles P. Boyer, Krzysztof Galicki, Santiago R. Simanca

We study the Sasaki cone of a CR structure of Sasaki type on a given closed manifold. We introduce an energy functional over the cone, and use its critical points to single out the strongly extremal Reeb vectors fields. Should one such vector field be a member of the extremal set, the scalar curvature of a Sasaki extremal metric representing it would have th

Ilya L. Shapiro

We present brief, to great extent pedagogical review on renormalization in curved space-time and of some recent results on the derivation and better understanding of quantum corrections to the action of gravity. The paper is mainly devoted to the semiclassical approach, but we also discuss its importance for quantum gravity and string theory.

Chiaki Kobayashi, Ken'ichi Nomoto

We construct a new model of Type Ia Supernovae (SNe Ia), based on the single degenerate scenario, taking account of the metallicity dependences of the white dwarf (WD) wind and the mass-stripping effect on the binary companion star. Our model naturally predicts that the SN Ia lifetime distribution spans a range of 0.1-20 Gyr with the double peaks at ~0.1 and

M. U. Akhmet

A multidimensional chaos is generated by a special initial value problem for the non-autonomous impulsive differential equation. The existence of a chaotic attractor is shown, where density of periodic solutions, sensitivity of solutions and existence of a trajectory dense in the set of all orbits are observed. The chaotic properties of all solutions are dis

Irina Maximenko

We make an estimation of the support of a multivariable scaling function for an arbitrary dilation matrix. We give a method of calculating the values of the scaling function on a tight set using the knowledge of the size of the support.

K. A. Viarenich, V. L. Kalashnikov, S. L. Cherkas

Two approaches to quantization of Freedman's closed Universe are compared. In the first approach, the Shrodinger's norm of the wave function of Universe is used, and in the second approach, the Klein-Gordon's norm is used. The second one allows building the quasi-Heisenberg operators as functions of time and finding their average values. It is shown that the

Naoto Kobayashi, Chikako Yasui, Alan T. Tokunaga, Masao Saito

The extreme outer Galaxy (EOG) has a very different environment from that in the solar neighborhood, with low metallicity (less than -0.5 dex), much lower gas density, and small or no perturbation from spiral arms. The EOG is an excellent laboratory for the study of the star formation processes that happened during the formation period of the Galaxy. In part

Jin Min Yang

Since the top quark FCNC processes are extremely supressed in the Standard Model (SM) but could be greatly enhanced in some new physics models, they could serve as a smoking gun for new physics hunting at the LHC. In this brief review we summarize the new physics predictions for various top quark FCNC processes at the LHC by focusing on two typical models: t

Stefano Galatolo, Mathieu Hoyrup, Cristobal Rojas

We consider the dynamical behavior of Martin-L\"of random points in dynamical systems over metric spaces with a computable dynamics and a computable invariant measure. We use computable partitions to define a sort of effective symbolic model for the dynamics. Through this construction we prove that such points have typical statistical behavior (the behavior

Claude Viterbo

The paper is wihdrawn due to a critical error in the argument using the spectral sequence

Myriam Maumy, B. Boulanger, W. Dewe, A. Gilbert

In the industries that involved either chemistry or biology, such as pharmaceutical industries, chemical industries or food industry, the analytical methods are the necessary eyes and hear of all the material produced or used. If the quality of an analytical method is doubtful, then the whole set of decision that will be based on those measures is questionab

Claude Viterbo

Let $H(q,p)$ be a Hamiltonian on $T^*T^n$. We show that the sequence $H_{k}(q,p)=H(kq,p)$ converges for the $\gamma$ topology defined by the author, to $\bar{H}(p)$. This is extended to the case where only some of the variables are homogenized, that is the sequence $H(kx,y,q,p)$ where the limit is of the type ${\bar H}(y,q,p)$ and thus yields an "effective H

Haijun Zhou

During the past decade, phase-transition phenomena in the random 3-satisfiability (3-SAT) problem has been intensively studied by statistical physics methods. In this work, we study the random 3-SAT problem by the mean-field first-step replica-symmetry-broken cavity theory at the limit of temperature $T\to 0$. The reweighting parameter $y$ of the cavity theo

Chikako Yasui, Naoto Kobayashi, Alan T. Tokunaga, Masao Saito

We are conducting a deep near-infrared (NIR) imaging survey of young embedded clusters in the extreme outer Galaxy (hereafter EOG), at the Galactic radius (R_g) of more than 18 kpc. The EOG is an excellent laboratory to study the nature of the IMF in a low-metallicity environment with a great advantage of the proximity compared to nearby dwarf galaxies, such

Mario I. Molina, Yuri S. Kivshar

We study light localization at a phase-slip defect created by two semi-infinite mismatched identical arrays of coupled optical waveguides. We demonstrate that the nonlinear defect modes possess the specific properties of both nonlinear surface modes and discrete solitons. We analyze stability of the localized modes and their generation in both linear and non

Petteri Kaski, Patric R. J. Östergård

We establish by means of a computer search that a complete graph on 14 vertices has 98,758,655,816,833,727,741,338,583,040 distinct and 1,132,835,421,602,062,347 nonisomorphic one-factorizations. The enumeration is constructive for the 10,305,262,573 isomorphism classes that admit a nontrivial automorphism.

Orfeu Bertolami, Francisco Gil Pedro, Morgan Le Delliou

We find that deviation from the virial equilibrium of the Abell Cluster A586 yields evidence of the interaction between dark matter and dark energy. We argue that this interaction might imply a violation of the Equivalence Principle. Our analysis show that evidence is found in the context of two different models of dark energy-dark matter interaction.

Rabin Banerjee, Bibhas Ranjan Majhi

We give a correction to the tunneling probability by taking into account the back reaction effect to the metric of the black hole spacetime. We then show how this gives rise to the modifications in the semiclassical black hole entropy and Hawking temperature. Finally, we reproduce the familiar logarithmic correction to the Bekenstein-Hawking area law.

Charles Bordenave, Marc Lelarge

We analyze the convergence of the spectrum of large random graphs to the spectrum of a limit infinite graph. We apply these results to graphs converging locally to trees and derive a new formula for the Stieljes transform of the spectral measure of such graphs. We illustrate our results on the uniform regular graphs, Erdos-Renyi graphs and preferential attac

Dirk Hofmann, Walter Tholen

For a quantale $\V$, first a closure-theoretic approach to completeness and separation in $\V$-categories is presented. This approach is then generalized to $\Tth$-categories, where $\Tth$ is a topological theory that entails a set monad $\mT$ and a compatible $\mT$-algebra structure on $\V$.

K. Kajantie, Jorma Louko, T. Tahkokallio

We find the three-dimensional gravity dual of a process in which two clouds of (1+1)-dimensional conformal matter moving in opposite directions collide. This gives the most general conformally invariant holographic flow in the 1+1 dimensional boundary theory in terms of two arbitrary functions. With a suitable choice of the arbitrary functions the process ca

P. A. Petrosyan

An interval edge t-coloring of a graph G is a proper edge coloring of G with colors 1,2...,t such that at least one edge of G is colored by color i,i=1,2...,t, and the edges incident with each vertex x are colored by d_{G}(x) consecutive colors, where d_{G}(x) is the degree of the vertex x in G. For Mobius ladders the existence of this coloring is proved and

Masahiko Egami, Hideki Iwaki

This paper considers an optimal life insurance for a householder subject to mortality risk. The household receives a wage income continuously, which is terminated by unexpected (premature) loss of earning power or (planned and intended) retirement, whichever happens first. In order to hedge the risk of losing income stream by householder's unpredictable even

Mark Andrews

We discuss four general features of force-free evolution: (1) The spatial spread of any packet changes with time in a very simple way. (2) Over sufficiently short periods of time (whose duration is related to the spread in momentum of the packet) the probability distribution moves but there is little change in shape. (3) After a sufficiently long period (rel

Svante Janson

It is well-known that a random variable, i.e., a function defined on a probability space, with values in a Borel space, can be represented on the special probability space consisting of the unit interval with Lebesgue measure. We show an extension of this to multivariate functions. This is motivated by some recent constructions of random graphs.

Juergen Jost, Yi-Hu Yang, Kang Zuo

In this note, we survey our recent work concerning cohomologies of harmonic bundles on quasi-compact Kaehler manifolds.

R. Inanc Baykur

The topology of broken Lefschetz fibrations is studied by means of handle decompositions. We consider a slight generalization of round handles, and describe the handle diagrams for all that appear in dimension four. We establish simplified handlebody and monodromy representations for a certain subclass of broken Lefschetz fibrations/pencils, while showing th

John E. Harper

We establish model category structures on algebras and modules over operads in symmetric spectra, and study when a morphism of operads induces a Quillen equivalence between corresponding categories of algebras (resp. modules) over operads.

John E. Harper

This paper studies the existence of model category structures on algebras and modules over operads in monoidal model categories.

H. Takeya, K. Ishida, K. Kitagawa, Y. Ihara

We have performed $^{69,71}$Ga nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) and muon spin rotation/resonance on the quasi two-dimensional antiferromagnet (AFM) NiGa$_2$S$_4$, in order to investigate its spin dynamics and magnetic state at low temperatures. Although there exists only one crystallographic site for Ga in NiGa$_2$S$_4$

Xiao-Gang He, Sandip Pakvasa

We study baryon number violating nucleon decays induced by unparticle interactions with the standard model particles. We find that the lowest dimension operators which cause nucleon decays can arise at dimension 6 + (d_s-3/2) with the unparticles being a spinor of dimension d_s=d_\U +1/2. For scalar and vector unparticles of dimension d_\U, the lowest order

Renjun Xu, Zhiming Liu, Yanming Ma, Tian Cui

We report a detailed ab initio investigation on hydrogen bonding, geometry, electronic structure, and lattice dynamics of ice under a large high pressure range, including the ice X phase (55-380GPa), the previous theoretically proposed higher-pressure phase ice XIIIM (Refs. 1-2) (380GPa), ice XV (a new structure we derived from ice XIIIM) (300-380GPa), as we

Renjun Xu, Zhiming Liu, Yanming Ma, Tian Cui

We report a detailed ab initio investigation on the optical properties of ice under a wide high pressure range. The ice X phase (up to 380GPa), the theoretical proposed higher pressure phase ice XV (300GPa), as well as the ambient pressure low-temperature phase ice XI are involved. Our results show that the dispersion relations of optical properties of ice u

Kazuhiko Minami

Fractal structure of the six-vertex model is introduced with the use of the IFS (Iterated Function Systems). The fractal dimension satisfies an equation written by the free energy of the six-vertex model. It is pointed out that the transfer matrix method and the $n$-equivalence relation introduced in lattice theories have also been introduced in the area of

Jun-Jin Peng, Shuang-Qing Wu

Motivated by the success of the recently proposed method of anomaly cancellation to derive Hawking fluxes from black hole horizons of spacetimes in various dimensions, we have further extended the covariant anomaly cancellation method shortly simplified by Banerjee and Kulkarni to explore the Hawking radiation of the (3+1)-dimensional charged rotating black

Ryan Hutchinson

It is known that maximum distance separable and maximum distance profile convolutional codes exist over large enough finite fields of any characteristic for all parameters $(n,k,\delta)$. It has been conjectured that the same is true for convolutional codes that are strongly maximum distance separable. Using methods from linear systems theory, we resolve thi

Fuquan Fang, Jianwen man, Zhenlei Zhang

We show that a complete Riemannian manifold has finite topological type (i.e., homeomorphic to the interior of a compact manifold with boundary), provided its Bakry-\'{E}mery Ricci tensor has a positive lower bound, and either of the following conditions: (i) the Ricci curvature is bounded from above; (ii) the Ricci curvature is bounded from below and inject

Le-Huy Nguyen, Hai-Siong Tan, Rajesh R. Parwani

A nonlinear Schrodinger equation, that had been obtained within the context of the maximum uncertainty principle, has the form of a difference-differential equation and exhibits some interesting properties. Here we discuss that equation in the regime where the nonlinearity length scale is large compared to the deBroglie wavelength; just as in the perturbativ

K2K Collaboration, S. Mine

The atmospheric neutrino background for proton decay to positron and neutral pion in ring imaging water Cherenkov detectors is studied with an artificial accelerator neutrino beam for the first time. In total, about 314,000 neutrino events corresponding to about 10 megaton-years of atmospheric neutrino interactions were collected by a 1,000 ton water Cherenk

Mizue Honda, Morimitsu Tanimoto

The tri-bimaximal mixing is a good approximation for the present data of neutrino mixing angles. The deviation from the tri-bimaximal mixing is discussed numerically in the framework of the A4 model. Values of \tan^2\theta_{12}, \sin^2 2\theta_{23} and |U_{e3}| deviate from the tri-bimaximal mixing due to the corrections of the vacuum alignment of flavon fie

Jiang-Tao Liu, Kai Chang

We suggest a new practical scheme for the direct detection of pure spin current by using the two-color Faraday rotation of optical quantum interference process (QUIP) in a semiconductor system. We demonstrate theoretically that the Faraday rotation of QUIP depends sensitively on the spin orientation and wave vector of the carriers, and can be tuned by the re

Yasushi Mino, Richard Price

The analysis of gravitational wave data may require greater accuracy than is afforded by the adiabatic approximation to the trajectory of and field produced by a particle moving in curved spacetime. Higher accuracy is available with a two-timescale approach using as an expansion parameter the ratio of orbital time to radiation reaction time. To avoid apparen

Ron Peled, Ariel Yadin, Amir Yehudayoff

A k-wise independent distribution on n bits is a joint distribution of the bits such that each k of them are independent. In this paper we consider k-wise independent distributions with identical marginals, each bit has probability p to be 1. We address the following question: how high can the probability that all the bits are 1 be, for such a distribution?

Ognjen Perisic, Hui Lu

Application of Jarzynski nonequilibrium work relation to free energy calculation is limited by the very slow convergence of the estimate when dissipation is high. We present a novel perturbation protocol able to improve the convergence of Jarzynski estimator when it is applied in the reconstruction of the potential of mean force. The improvement is based on

Dong Pyo Chi, Jeong Woon Choi, Jeong San Kim, Taewan Kim

We develop a three-party quantum secret sharing protocol based on arbitrary dimensional quantum states. In contrast to the previous quantum secret sharing protocols, the sender can always control the state, just using local operations, for adjusting the correlation of measurement directions of three parties and thus there is no waste of resource due to the d

Amir H. Fariborz

The highlights of studies of mixing among scalar mesons below and above 1 GeV within a nonlinear chiral Lagrangian framework is briefly presented. Two scalar meson nonets are introduced to explore the mass spectrum and decay properties of the $I$=1/2 and $I$=1 scalar states. For the $I$=0 states, in addition to these two nonets a scalar glueball component is

A. N. Gorban, N. R. Sumner, A. Y. Zinovyev

Multidimensional data distributions can have complex topologies and variable local dimensions. To approximate complex data, we propose a new type of low-dimensional ``principal object'': a principal cubic complex. This complex is a generalization of linear and non-linear principal manifolds and includes them as a particular case. To construct such an object,

Scott A. Wolpert

A summary introduction of the Weil-Petersson metric space geometry is presented. Teichmueller space and its augmentation are described in terms of Fenchel-Nielsen coordinates. Formulas for the gradients and Hessians of geodesic-length functions are presented. Applications are considered. A description of the Weil-Petersson metric in Fenchel-Nielsen coordinat

David Chataur, Luc Menichi

Let $G$ be a finite group or a compact connected Lie group and let $BG$ be its classifying space. Let $\mathcal{L}BG:=map(S^1,BG)$ be the free loop space of $BG$ i.e. the space of continuous maps from the circle $S^1$ to $BG$. The purpose of this paper is to study the singular homology $H_*(\mathcal LBG)$ of this loop space. We prove that when taken with coe

Alberto Canonaco

We prove a general theorem that gives a non trivial relation in the group of derived autoequivalences of a variety (or stack) X, under the assumption that there exists a suitable functor from the derived category of another variety Y admitting a full exceptional sequence. Applications include the case in which X is Calabi-Yau and either X is a hypersurface i

M. Yu. Khlopov

A widely accepted viewpoint is to consider candidates for cosmological dark matter as neutral and weakly interacting particles, as well as to consider only light elements in the pregalactic chemical composition. It is shown that stable charged leptons and quarks can exist and, hidden in elusive atoms, play the role of dark matter. The inevitable consequence

Lyonell Boulton, Michael Levitin, Marco Marletta

We prove that the spectrum of a certain PT-symmetric periodic problem is purely real. Our results extend to a larger class of potentials those recently found by Brian Davies [math.SP/0702122] and John Weir [arXiv:0711.1371].

M. Sztyren

The present paper develops the ideas introduced in {\em cond-mat/0312673}. The construction of a hybrid discrete-continuous model of layered superconductors is briefly presented. The model bases on the classic Lawrence-Doniach scenario with admitting, however, long-range interactions between atomic planes. Moreover, apart from Josephson couplings they involv

A. N. Gorban, A. Y. Zinovyev

Principal manifolds are defined as lines or surfaces passing through ``the middle'' of data distribution. Linear principal manifolds (Principal Components Analysis) are routinely used for dimension reduction, noise filtering and data visualization. Recently, methods for constructing non-linear principal manifolds were proposed, including our elastic maps app

Isaac Gorelic

We extend the scope of B. Shapirovskii's results [B.E Shapirovskii, "Cardinal invariants in Compact Hausdorff Spaces," Amer. Math. Soc. Transl. (2) Vol. 134, 1987, pp. 93-118] on the order of $\pi$-bases in compact spaces and answer some questions of V. Tkachuk in [V.V. Tkachuk, "Point-countable pi-bases in first-countable and similar spaces," Fund. Math. 18

M. Yu. Khlopov

Primordial black holes (PBHs) are a profound signature of primordial cosmological structures and provide a theoretical tool to study nontrivial physics of the early Universe. The mechanisms of PBH formation are discussed and observational constraints on the PBH spectrum, or effects of PBH evaporation, are shown to restrict a wide range of particle physics mo

M. Yu. Khlopov

Particle physics candidates for cosmological dark matter are usually considered as neutral and weakly interacting. However stable charged leptons and quarks can also exist and, hidden in elusive atoms, play the role of dark matter. The necessary condition for such scenario is absence of stable particles with charge -1 and effective mechanism for suppression

Ruslan Sharipov

A cubic identity for the Infeld-van der Waerden field is found and its application to verifying an explicit formula for the spinor components of the metric connection is demonstrated.

Joseph D. Meiring, Varsha P. Kulkarni, James T. Lauroesch, Celine Peroux

We present chemical abundance measurements from medium resolution observations of 8 sub-damped Lyman-alpha absorber and 2 strong Lyman-limit systems at z < 1.5 observed with the MIKE spectrograph on the 6.5m Magellan II Clay telescope. These observations were taken as part of an ongoing project to determine abundances in z < 1.5 quasar absorption line system

Daniele Alessandrini

In this paper we construct a compactification for the parameter space of convex projective structures on a fixed n-manifold M. This parameter space is a closed semi-algebraic subset of the variety of characters of representations of the fundamental group of M in SL_{n+1}(R). The boundary is the inverse limit of an inverse system of logarithmic limit sets of

Neil Dobbs, Bartlomiej Skorulski

We show that for entire maps of the form $z \mapsto \lambda \exp(z)$ such that the orbit of zero is bounded and such that Lebesgue almost every point is transitive, no absolutely continuous invariant probability measure can exist. This answers a long-standing open problem.

Toshiharu Nakagawa, Hideki Ishihara, Ken Matsuno, Shinya Tomizawa

We construct a new charged rotating Kaluza-Klein black hole solution in the five-dimensional Einstein-Maxwell theory with a Chern-Simon term. The features of the solutions are also investigated. The spacetime is asymptotically locally flat, i.e., it asymptotes to a twisted $\rm S^1$ bundle over the four-dimensional Minkowski spacetime. The solution describe

Lynne A. Hillenbrand, John M. Carpenter, Jinyoung Serena Kim, Michael R. Meyer

(abbreviated) We report detection with the Spitzer Space Telescope of cool dust surrounding solar type stars. The observations were performed as part of the Legacy Science Program, ``Formation and Evolution of Planetary Systems'' (FEPS). From the overall FEPS sample (Meyer et al. 2006) of 328 stars having ages ~0.003-3 Gyr we have selected sources with 70 um

Sergey A. Gaifullin

In 1973 V.L.Popov classified affine SL(2)-embeddings. He proved that a locally transitive SL(2)-action on a normal affine three-dimensional variety X is uniquely determined by a pair (p/q, r), where 0<p/q<=1 is an uncancelled fraction and r is a positive integer. Here r is the order of the stabilizer of a generic point. In this paper we show that the variety