November 2010 arXiv papers — page 60

I. A. Kowalik, A. Persson, M. Á. Niño, A. Navarro-Quezada

We employ x-ray spectroscopy to characterize the distribution and magnetism of particular alloy constituents in (Ga,Fe)N films grown by metal organic vapor phase epitaxy. Furthermore, photoelectron microscopy gives direct evidence for the aggregation of Fe ions, leading to the formation of Fe-rich nanoregions adjacent to the samples surface. A sizable x-ray

Juan Elias

In 1978 Lipman presented a proof of the existence of a desingularization for any excellent surface. The strategy of Lipman's proof is based on the finiteness of the number H(R) defined as the supreme of the second Hilbert-Samuel coefficient I, where I range the set of normal m-primary ideals of a Noetherian complete local ring (R,m). The problem studied

B. Pire, L. Szymanowski

We describe a new way to access the chiral odd transversity parton distribution in the proton through the photoproduction of lepton pairs on transversely polarized target. The basic ingredient is the interference of the Bethe Heitler or Drell-Yan amplitudes with the amplitude of a process, where the photon couples to quarks through its twist-2 chiral-odd dis

Maria M. de Castro, Miguel Angel Garcia March, Damia Gomila, Roberta Zambrini

The effects of an intracavity photonic crystal in a multimode optical parametric oscillator are studied, with a special focus on quantum fluctuations. The capability to either stimulate or inhibit the spatial instability, lowering or increasing the parametric threshold, allows to control the intensity fluctuations and correlations. A significative quantum no

Valentin D. Gladush, Marina V. Galadgyi

We propose the method of investigation of radial motions for charged and neutral test particles in the Reissner-Nordström field by means of mass potential. In this context we analyze special features of interaction of charges and their motions in General Relativity and construct the radial motion classification. For test particles and a central source with c

Valentin D. Gladush

The radial motion of a self-graviting charged dust and stability condition of the static charged dust spheres are considered. The stability is possible for the bound states of the weakly charged layer with abnormal charge with respect to the active mass.

V. Loriot, P. Béjot, W. Ettoumi, Y. Petit

As a contribution to the ongoing controversy about the role of higher-order Kerr effect (HOKE) in laser filamentation, we first provide thorough details about the protocol that has been employed to infer the HOKE indices from the experiment. Next, we discuss potential sources of artifact in the experimental measurements of these terms and show that neither t

M. El Beiyad, B. Pire, L. Szymanowski, S. Wallon

We first describe a new way to access the chiral odd transversity parton distribution in the proton through the photoproduction of lepton pairs. The basic ingredient is the interference of the usual Bethe-Heitler or Drell-Yan amplitudes with the amplitude of a process, where the photon couples to quarks through its chiral-odd distribution amplitude, which is

Federico Bassetti, Lucia Ladelli, Giuseppe Toscani

We introduce a class of Kac-like kinetic equations on the real line, with general random collisional rules, which include as particular cases models for wealth redistribution in an agent-based market or models for granular gases with a background heat bath. Conditions on these collisional rules which guarantee both the existence and uniqueness of equilibrium

F. Markert, P. Würtz, A. Koglbauer, T. Gericke

We have measured the AC-Stark shift of the $14D_{5/2}$ Rydberg state of rubidium 87 in an optical dipole trap formed by a focussed CO$_2$-laser. We find good quantitative agreement with the model of a free electron experiencing a ponderomotive potential in the light field. In order to reproduce the observed spectra we take into account the broadening of the

Ziheng Lin, Hwee Tou Ng, Min-Yen Kan

We have developed a full discourse parser in the Penn Discourse Treebank (PDTB) style. Our trained parser first identifies all discourse and non-discourse relations, locates and labels their arguments, and then classifies their relation types. When appropriate, the attribution spans to these relations are also determined. We present a comprehensive evaluatio

Simon Barthelme, Magali Beffy, Nicolas Chopin, Arnaud Doucet

This is a collection of discussions of `Riemann manifold Langevin and Hamiltonian Monte Carlo methods" by Girolami and Calderhead, to appear in the Journal of the Royal Statistical Society, Series B.

Oğul Esen, Hasan Gümral

We show that complete cotangent lifts of vector fields, their decomposition into vertical representative and holonomic part provide a geometrical framework underlying Eulerian equations of continuum mechanics. We discuss Euler equations for ideal incompressible fluid and Vlasov equations of plasma dynamics in connection with the lifts of divergence-free and

J. Kaluzny, I. B. Thompson, W. Krzeminski, K. Zloczewski

We report time-series photometry for 55 variable stars located in the central part of the globular cluster M55. The sample includes 28 newly identified objects of which 13 are eclipsing binaries. Three of these are detached systems located in the turn-off region on the cluster color-magnitude diagram. Two of them are proper motion (PM) members of M55 and are

Peihao Huang, Hang Zheng, Keiichiro Nasu

The dynamics of a qubit in a structured environment is investigated theoretically. One point of view of the model is the spin-boson model with a Lorentz shaped spectral density. An alternative view is a qubit coupled to harmonic oscillator (HO), which in turn coupled to a Ohmic environment. Two different methods are applied and compared for this problem. One

Jing Wang, Guinevere Kauffmann, Roderik Overzier, Barbara Catinella

We analyze a sample of galaxies with stellar masses greater than $10^{10} M_{\odot}$ and with redshifts in the range $0.025<z<0.05$ for which HI mass measurements are available from the GALEX Arecibo SDSS Survey (GASS) or from the Arecibo Legacy Fast ALFA survey (ALFALFA). At a given value of $M_*$, our sample consists primarily of galaxies that are more HI-

Nicola Moreni, Andrea Pallavicini

For a long time interest-rate models were built on a single yield curve used both for discounting and forwarding. However, the crisis that has affected financial markets in the last years led market players to revise this assumption and accommodate basis-swap spreads, whose remarkable widening can no longer be neglected. In recent literature we find many pro

Alexandre Mouton, Emmanuel Frenod

In this paper, we present some new results about the approximation of the Vlasov-Poisson system with a strong external magnetic field by the 2D finite Larmor radius model. The proofs within the present work are built by using two-scale convergence tools, and can be viewed as a new slant on previous works of Frénod and Sonnendrücker and Bostan on the 2D finit

Jaromir Fiurasek

We propose an entanglement distillation and purification scheme for symmetric two-mode entangled Gaussian states that allows to asymptotically extract a pure entangled Gaussian state from any input entangled symmetric Gaussian state. The proposed scheme is a modified and extended version of the entanglement distillation protocol originally developed by [Brow

I. Schulday, R. Lawall, J. Barth, K. -H. Glander

The reactions $γp \rightarrow K^{+}Σ^{\pm}π^{\mp}$ were studied with the SAPHIR detector using a tagged photon beam at the electron stretcher facility ELSA in Bonn. The decays $Σ^{-} \rightarrow nπ^{-}$ and $Σ^{+} \rightarrow nπ^{+}, pπ^0$ were fully reconstructed. Reaction cross sections were measured as a function of the photon energy from threshold up to

F. W. Wieland, J. Barth, K. -H. Glander, J. Hannappel

The reaction $γp \TO K^+Λ(1520)$ was measured in the energy range from threshold to 2.65 GeV with the SAPHIR detector at the electron stretcher facility ELSA in Bonn. The $Λ(1520)$ production cross section was analyzed in the decay modes $pK^-$, $n \bar{K}^0$, $Σ^{\pm}π^{\mp}$, and $Λπ^+π^-$ as a function of the photon energy and the squared four-momentum tr

T. Lappi

The physics of the initial conditions of heavy ion collisions is dominated by the nonlinear gluonic interactions of QCD. These lead to the concepts of parton saturation and the Color Glass Condensate (CGC). We discuss recent progress in calculating multi-gluon correlations in this framework, prompted by the observation that these correlations are in fact eas

Ryan Martin, Jianchun Zhang, Chuanhai Liu

The Dempster--Shafer (DS) theory is a powerful tool for probabilistic reasoning based on a formal calculus for combining evidence. DS theory has been widely used in computer science and engineering applications, but has yet to reach the statistical mainstream, perhaps because the DS belief functions do not satisfy long-run frequency properties. Recently, two

Eran Amit, Amit Keren

The critical doping levels in cuprates, where the ground state changes its nature (from an antiferromagnet to a spin glass to superconductor to metal), are not universal. We investigate the origin of these critical doping variations by measuring the in-plane oxygen $p_σ$ hole density in the CuO$_{2}$ layers as a function of the oxygen density $y$ in (Ca$_{x}

Fermi LAT Collaboration

We report an analysis of the interstellar $γ$-ray emission in the third Galactic quadrant measured by the {Fermi} Large Area Telescope. The window encompassing the Galactic plane from longitude $210\arcdeg$ to $250\arcdeg$ has kinematically well-defined segments of the Local and the Perseus arms, suitable to study the cosmic-ray densities across the outer Ga

George Thomas, Ramandeep S. Johal

We study the 1-d isotropic Heisenberg model of two spin-1/2 systems as a quantum heat engine. The engine undergoes a four-step Otto cycle where the two adiabatic branches involve changing the external magnetic field at a fixed value of the coupling constant. We find conditions for the engine efficiency to be higher than the uncoupled model; in particular, we

Kingshook Biswas, Ricardo Perez-Marco

We consider simply connected log-Riemann surfaces with a finite number of ramification points. We prove that these surfaces are biholomorphic to C with uniformizations given by entire functions of the form F (z) = \int Q(z) e^{P(z)} dz where P, Q are polynomials of degrees equal to the number of infinite and finite order ramification points respectively. Con

Jan Gehrke, Jörg Main, Günter Wunner

The existence of periodic orbit bunches is proven for the diamagnetic Kepler problem. Members of each bunch are reconnected differently at self-encounters in phase space but have nearly equal classical action and stability parameters. Orbits can be grouped already on the level of the symbolic dynamics by application of appropriate reconnection rules to the s

Nell Sedransk, Lawrence H. Cox, Deborah Nolan, Keith Soper

Putting data into the public domain is not the same thing as making those data accessible for intelligent analysis. A distinguished group of editors and experts who were already engaged in one way or another with the issues inherent in making research data public came together with statisticians to initiate a dialogue about policies and practicalities of req

M. R. Setare, V. Kamali

We show that extremal Kerr-Bolt spacetimes have a hidden conformal symmetry. In this regard, we consider the wave equation of a massless scalar field propagating in extremal Kerr-Bolt spacetimes and find in the &#34;near region&#34;, the wave equation in extremal limit can be written in terms of the $SL(2,R)$ quadratic Casimir. Moreover, we obtain the micros

V. V. Anisovich, L. G. Dakhno, M. A. Matveev, V. A. Nikonov

We discuss a collective effect, which can be possible in hadron--hadron collisions at superhigh energies, that is, a quasi-diffraction production of several white clusters of quarks and gluons. Being transformed into hadrons, such clusters are sources of the fastest particles, which move forward nearly parallel to each other.

Yingying Wang, Zhenhua Ni, Hailong Hu, Yufeng Hao

In this paper, we report our study on gold (Au) films with different thicknesses deposited on single layer graphene (SLG) as surface enhanced Raman scattering (SERS) substrates for the characterization of rhodamine (R6G) molecules. We find that an Au film with a thickness of ~7 nm deposited on SLG is an ideal substrate for SERS, giving the strongest Raman si

Veena S. Parvathi, Ulysses J. Sofia, Jayant Murthy, B. R. S. Babu

We present interstellar C II (1334.5323 Å) and C II* (1335.7077 Å) column density measurements along 14 Galactic sight-lines. These sight-lines sample a variety of Galactic disk environments and include paths that range nearly two orders of magnitude in average hydrogen densities (<n(H)>) along the lines of sight. Five of the sight-lines show super-Solar gas

Kei-ichi Nagai, Maria Georgina Carrillo-Ruiz, Gergana Koleva, Randy Lewis

We explore aspects of the phase structure of SU(2) and SU(3) lattice gauge theories at strong coupling with many flavours $N_f$ of Wilson fermions in the fundamental representation, including the relevance to recent searches for a conformal window. The pseudoscalar meson mass, the quark mass and other quantities are observed as functions of the hopping param

Kazem Haghnejad Azar

For Banach left and right module actions, we will establish the relationships between topological centers of module actions with some result in the weak amenability of Banach algebras.

Kazem Haghnejad

Let $A$ be a Banach algebra and $A^{**}$ be the second dual of it. We show that by some new conditions, $A$ is weakly amenable whenever $A^{**}$ is weakly amenable. We will study this problem under generalization, that is, if $(n+2)-th$ dual of $A$, $A^{(n+2)}$, is $T-S-$weakly amenable, then $A^{(n)}$ is $T-S-$weakly amenable where $T$ and $S$ are continuou

P. Bhargavi, S. Jyothi

This paper details the application of a genetic programming framework for classification of decision tree of Soil data to classify soil texture. The database contains measurements of soil profile data. We have applied GATree for generating classification decision tree. GATree is a decision tree builder that is based on Genetic Algorithms (GAs). The idea behi

A. G. Kosovichev, S. Basu, R. Bogart, T. L. Duvall

Local helioseismology provides unique information about the subsurface structure and dynamics of sunspots and active regions. However, because of complexity of sunspot regions local helioseismology diagnostics require careful analysis of systematic uncertainties and physical interpretation of the inversion results. We present new results of comparison of the

Adam J. Burgasser, Daniella C. Bardalez Gagliuffi, John E. Gizis

We present a detailed examination of the brown dwarf multiples 2MASS J08503593+1057156 and 2MASS J17281150+3948593, both suspected of harboring components that straddle the L dwarf/T dwarf transition. Resolved photometry from Hubble Space Telescope/NICMOS show opposite trends in the relative colors of the components, with the secondary of 2MASS J0850+1057 be

Martin A. Cordiner, Nick L. J. Cox, Christopher J. Evans, Carrie Trundle

We present the largest sample to-date of intermediate-resolution blue-to-red optical spectra of B-type supergiants in M31 and undertake the first survey of diffuse interstellar bands (DIBs) in this galaxy. Spectral classifications, radial velocities and interstellar reddenings are presented for 34 stars in three regions of M31. Radial velocities and equivale

Xiaoxia Fan, Yanfeng Luo

In this paper, it is shown that the graph $T_4(p,q,r)$ is determined by its Laplacian spectrum and there are no two non-isomorphic such graphs which are cospectral with respect to adjacency spectrum.

Lawrence W. Baggett, Kathy D. Merrill, Judith A. Packer, Arlan B. Ramsay

The measure on generalized solenoids constructed using filters by Dutkay and Jorgensen is analyzed further by writing the solenoid as the product of a torus and a Cantor set. Using this decomposition, key differences are revealed between solenoid measures associated with classical filters in $\mathbb R^d$ and those associated with filters on inflated fractal

Jie Jiang, Hao Wu, Boling Guo

We study a coupled nonlinear evolution system arising from the Ginzburg-Landau theory for atomic Fermi gases near the BCS-BEC crossover. First, we prove that the initial boundary value problem generates a strongly continuous semigroup on a suitable phase-space which possesses the global attractor. Then we establish the existence of an exponential attractor.

Cynthia Dhinakaran, Dhinaharan Nagamalai, Jae Kwang Lee

Spam messages muddle up users inbox, consume network resources, and build up DDoS attacks, spread malware. Our goal is to present a definite figure about the characteristics of spam and spam vulnerable email accounts. These evaluations help us to enhance the existing technology to combat spam effectively. We collected 400 thousand spam mails from a spam trap

Mr. Chong Han, Dr. Ido Nevat, Dr. Gareth Peters, Prof. Jinhong Yuan

Bayesian filtering is a general framework for recursively estimating the state of a dynamical system. Classical solutions such that Kalman filter and Particle filter are introduced in this report. Gaussian processes have been introduced as a non-parametric technique for system estimation from supervision learning. For the thesis project, we intend to propose

S. V. Marchenko, A. F. J. Moffat, P. A. Crowther

In 1997 and 2008 we used the WFPC2 camera on board of the Hubble Space Telescope to obtain two sets of narrow-band H$α$ images of the runaway Wolf-Rayet (WR) star WR 124 surrounded by its nebula M1-67. This two-epoch imaging provides an expansion parallax and thus a practically assumption-free geometric distance to the nebula, d=3.35 +/- 0.67 kpc. Combined w

Mark Andrea de Cataldo

This is a report on joint work with T. Hausel and L. Migliorini, where we prove, for each of the groups GL(2,C), PGL(2,C), SL(2,C), that the non-Abelian Hodge theorem identifies the weight filtration on the cohomology of the character variety with the perverse Leray filtration on the cohomology of the domain of the Hitchin map. We review the decomposition th

A. Changjan, P. Udomsamuthirun

The upper critical field, the lower critical field and the critical magnetic field ratio of anisotropic magnetic superconductors are calculated by Ginzburg-Landau theory analytically. The effect of the Ginzburg-Landau parameter(κ_0), magnetic susceptibility(χ) and magnetic-to- anisotropic parameter ratio(θ) on the critical field ratio are considered. We find

S. M. Dougherty, V. Trenton, A. J. Beasley

A campaign of 35 epochs of milli-arcsecond resolution VLBA observations of the archetype colliding wind WR+O star binary system WR140 show the wind-collision region (WCR) as a bow-shaped arc of emission that rotates as the highly eccentric orbit progresses. The observations comprise 21 epochs from the 1993-2001 orbit, discussed by Dougherty et al. (2005), an

E. R. Parkin, J. M. Pittard, M. F. Corcoran, K. Hamaguchi

Three dimensional (3D) adaptive-mesh refinement (AMR) hydrodynamical simulations of the wind-wind collision between the enigmatic super-massive star \etacar and its mysterious companion star are presented which include radiative driving of the stellar winds, gravity, optically-thin radiative cooling, and orbital motion. Simulations with static stars with a p

M. Kennedy, S. M. Dougherty, P. M. Williams, A. Fink

Archival observations from the Very Large Array (VLA) at frequencies between 1.4 GHz and 43 GHz of the 6.6-day O6.5-7+O5.5-6 binary Cyg OB2 #5 over 20 years are re-examined. The aim is to determine the location and character of its known variable radio emission. The radio emission consists of a primary component associated with the binary, and a non-thermal

Dhruv Parthasarathy, Devavrat Shah, Tauhid Zaman

Communities in social networks or graphs are sets of well-connected, overlapping vertices. The effectiveness of a community detection algorithm is determined by accuracy in finding the ground-truth communities and ability to scale with the size of the data. In this work, we provide three contributions. First, we show that a popular measure of accuracy known

W. X. Tang, D. M. Paganin

We propose a spin polarized Talbot effect for an electron beam scattered from a grating of magnetic nanostructures. Existing periodic magnetic nanostructures can be used in conjunction with electron-beam illumination to create a spin polarized replica of the transversely periodic exit surface beam a Talbot length away. Experiments have been proposed to verif

S. Lupi, L. Baldassarre, B. Mansart, A. Perucchi

V2O3 is the prototype system for the Mott transition, one of the most fundamental phenomena of electronic correlation. Temperature, doping or pressure induce a metal to insulator transition (MIT) between a paramagnetic metal (PM) and a paramagnetic insulator (PI). This or related MITs have a high technological potential, among others for intelligent windows

Ariel Afek, Eugene I. Shakhnovich, David B. Lukatsky

Numerous experiments demonstrate a high level of promiscuity and structural disorder in organismal proteomes. Here we ask the question what makes a protein promiscuous, i.e., prone to non-specific interactions, and structurally disordered. We predict that multi-scale correlations of amino acid positions within protein sequences statistically enhance the prop

Robert J. Finkelstein

We discuss flavor states of the knot model and their relation to the KM and the PMNS matrices. These states are eigenstates of absorption-emission operators and are analogous to the coherent states of the Maxwell field. The underlying model has been proposed as a possible substructure of the standard model. We include a knot parameterization of the CKM matri

Michael Creutz, Taro Kimura, Tatsuhiro Misumi

We present a theoretical foundation for the Index theorem in naive and minimally doubled lattice fermions by studying the spectral flow of a Hermitean version of Dirac operators. We utilize the point splitting method to implement flavored mass terms, which play an important role in constructing proper Hermitean operators. We show the spectral flow correctly

Michael Gruber

We calculate the next-to-leading order perturbative corrections to the SVZ sum rules for the coupling f_N, the nucleon leading twist wave function at the origin. The results are compared to the established Ioffe sum rules and also to lattice QCD simulations.

Sonny Mantry, Frank Petriello

We study the low transverse momentum (p_T) distribution of the Z-boson at hadron colliders for p_T ~ Lambda_{QCD} using a factorization and resummation formula derived in the Soft Collinear Effective Theory (SCET). In the region p_T ~ Lambda_{QCD}, new non-perturbative effects arise that cannot be entirely captured by the standard parton distribution functio

V. Taufour, D. Aoki, G. Knebel, J. Flouquet

Precise resistivity measurements on the ferromagnetic superconductor UGe2 under pressure p and magnetic field H reveal a previously unobserved change of the anomaly at the Curie temperature. Therefore, the tricritical point (TCP) where the paramagnetic-to-ferromagnetic transition changes from a second order to a first order transition is located in the p-T p

Kathy L Cooksey, J. Xavier Prochaska, Christopher Thom, Hsiao-Wen Chen

We identified 24 SiIV absorption systems with z <~ 1 from a blind survey of 49 low-redshift quasars with archival Hubble Space Telescope ultraviolet spectra. We relied solely on the characteristic wavelength separation of the doublet to automatically detect candidates. After visual inspection, we defined a sample of 20 definite (group G = 1) and 4 &#34;highl

Takero Ibuki, Jun-ichi Inoue

Statistical properties of order-driven double-auction markets with Bid-Ask spread are investigated through the dynamical quantities such as response function. We first attempt to utilize the so-called {\it Madhavan-Richardson-Roomans model} (MRR for short) to simulate the stochastic process of the price-change in empirical data sets (say, EUR/JPY or USD/JPY

Paul D. Lasky, Daniela D. Doneva

The imminent detection of gravitational waves will trigger precision tests of gravity through observations of quasinormal ringing of black holes. While General Relativity predicts just two polarizations of gravitational waves, the so-called plus and cross polarizations, numerous alternative theories of gravity predict up to six different polarizations which

Antonio Delgado, Kenneth Lane, Adam Martin

In addition to the narrow spin-one resonances $ρ_T$, $ω_T$ and $a_T$ occurring in low-scale technicolor, there will be relatively narrow scalars in the mass range 200 to 600--700 GeV. We study the lightest isoscalar state, $σ_T$. In several important respects it is like a heavy Higgs boson with a small vev. It may be discovered with high luminosity at the LH

Karin Baur, Bethany Marsh

We give a geometric model for a tube category in terms of homotopy classes of oriented arcs in an annulus with marked points on its boundary. In particular, we interpret the dimensions of extension groups of degree 1 between indecomposable objects in terms of negative geometric intersection numbers between corresponding arcs, giving a geometric interpretatio

Helvi Witek, Vitor Cardoso, Leonardo Gualtieri, Carlos Herdeiro

We study head-on collisions of unequal mass black hole binaries in D=5 space-time dimensions, with mass ratios between 1:1 and 1:4. Information about gravitational radiation is extracted by using the Kodama-Ishibashi gauge-invariant formalism and details of the apparent horizon of the final black hole. For the first time, we present waveforms, total integrat

Hongki Min, E. H. Hwang, S. Das Sarma

We develop a theory for the temperature and density dependence of phonon-limited resistivity $ρ(T)$ in bilayer and multilayer graphene, and compare with the corresponding monolayer result. For the unscreened case, we find $ρ\approx C T$ with $C \propto v_{\rm F}^{-2}$ in the high-temperature limit, and $ρ\approx A T^4$ with $A \propto v_{\rm F}^{-2} k_{\rm F

Yongqing Huang, Anzhong Wang

In this paper, we investigate three important issues: stability, ghost and strong coupling, in the Horava-Melby-Thompson setup of the Horava-Lifshitz theory with $λ\not= 1$, generalized recently by da Silva. We first develop the general linear scalar perturbations of the Friedmann-Robertson-Walker (FRW) universe with arbitrary spatial curvature, and find tha

Shamik Gupta, David Mukamel

Systems with long-range interactions, while relaxing towards equilibrium, sometimes get trapped in long-lived non-Boltzmann quasistationary states (QSS) which have lifetimes that grow algebraically with the system size. Such states have been observed in models of globally coupled particles that move under Hamiltonian dynamics either on a unit circle or on a

L. Christensen, J. P. U. Fynbo, J. X. Prochaska, C. C. Thoene

We present a composite spectrum of 60 long duration gamma-ray burst (GRB) afterglows with redshifts in the range 0.35<z<6.7 observed with low resolution optical spectra. The composite spectrum covers the wavelength range 700-6600 A in the rest frame and has a mean signal-to-noise ratio of 150 per 1 A pixel and reaches a maximum of ~300 in the range 2500-3500

Ryan Cooke, Max Pettini, Charles C. Steidel, Gwen C. Rudie

We present high resolution observations of an extremely metal-poor damped Lyman-alpha system, at z_abs = 2.3400972 in the spectrum of the QSO J0035-0918, exhibiting an abundance pattern consistent with model predictions for the supernova yields of Population III stars. Specifically, this DLA has [Fe/H] = -3.04, shows a clear `odd-even&#39; effect, and is C-r

Kimmo Kainulainen, Valerio Marra

We revise and extend the stochastic approach to cumulative weak lensing (hereafter the sGL method) first introduced in Ref. [1]. Here we include a realistic halo mass function and density profiles to model the distribution of mass between and within galaxies, galaxy groups and galaxy clusters. We also introduce a modeling of the filamentary large-scale struc

Riccardo Barbieri, Enrico Bertuzzo, Marco Farina, Paolo Lodone

In a supersymmetric model with hierarchical squark masses we analyze a pattern of flavour symmetry breaking centered on the special role of the top Yukawa coupling and, by extension, of the full Yukawa couplings for the up-type quarks. For sufficiently heavy squarks of the first and second generation this leads to effective Minimal Flavour Violation of the F

Randall Kelley, Lisa Randall, Brian Shuve

Resonance searches generally focus on narrow states that would produce a sharp peak rising over background. Early LHC running will, however, be sensitive primarily to broad resonances. In this paper we demonstrate that statistical methods should suffice to find broad resonances and distinguish them from both background and contact interactions over a large r

Vijay Kumar, Daniel S. Park, Washington Taylor

We systematically investigate the finite set of possible gauge groups and matter content for N = 1 supergravity theories in six dimensions with no tensor multiplets, focusing on nonabelian gauge groups which are a product of SU(N) factors. We identify a number of models which obey all known low-energy consistency conditions, but which have no known string th

Nachiketa Chakraborty, Brian D. Fields, Keith A. Olive

We explore a nuclear physics resolution to the discrepancy between the predicted standard big-bang nucleosynthesis (BBN) abundance of 7Li and its observational determination in metal-poor stars. The theoretical 7Li abundance is 3-4 times greater than the observational values, assuming the baryon-to-photon ratio, eta_wmap, determined by WMAP. The 7Li problem

Zhizhang Xie

We prove an analogue for odd dimensional manifolds with boundary, in the $b$-calculus setting, of the higher Atiyah-Patodi-Singer index theorem by Getzler and Wu, thus obtain a natural counterpart of the eta invariant for even dimensional closed manifolds.

Will Grilliette

In this work, I address a primary issue with adapting categorical and algebraic concepts to functional analytic settings, the lack of free objects. Using a &#34;normed set&#34; and associated categories, I describe constructions of normed objects, which build from a set to a vector space to an algebra, and thus parallel the natural progression found in algeb

Jing Chen, Andrew Drucker

BellQMA protocols are a subclass of multi-prover quantum Merlin-Arthur protocols in which the verifier is restricted to perform nonadaptive,unentangled measurements on the quantum states received from each Merlin. In this paper, we prove that m-clause 3-SAT instances have BellQMA proofs of satisfiability with constant soundness gap, in which O(sqrt(m)polylog

Raphael Bousso, Ben Freivogel, Stefan Leichenauer, Vladimir Rosenhaus

Without assuming necessary conditions for observers such as galaxies or entropy production, we show that the causal patch measure predicts the coincidence of vacuum energy and present matter density. Their common scale, and thus the enormous size of the visible universe, has its origin in the number of metastable vacua in the landscape.

Chen Lizhu, Pan Xue, Xiong Fengbo, Li Lin

With the help of transport and statistical models, we find that the ratios of higher net-proton cumulants measured at RHIC are dominated by the statistical fluctuations. Future measurements should focus on the dynamical fluctuations, which are relevant to the underlying mechanisms of particle production, the critical phenomena in particular. We also demonstr

Rina Anno, Timothy Logvinenko

We introduce a relative version of the spherical objects of Seidel and Thomas. Define an object E in the derived category D(Z x X) to be spherical over Z if the corresponding functor from D(Z) to D(X) gives rise to autoequivalences of D(Z) and D(X) in a certain natural way. Most known examples come from subschemes of X fibred over Z. This categorifies to the

Jesse Johnson, Darryl McCullough

For a Heegaard surface F in a closed orientable 3-manifold M, H(M,F) = Diff(M)/Diff(M,F) is the space of Heegaard surfaces equivalent to the Heegaard splitting (M,F). Its path components are the isotopy classes of Heegaard splittings equivalent to (M,F). We describe H(M,F) in terms of Diff(M) and the Goeritz group of (M,F). In particular, for hyperbolic M ea

W. Patrick Hooper

We study the symmetries and geodesics of an infinite translation surface which arises as a limit of translation surfaces built from regular polygons, studied by Veech. We find the affine symmetry group of this infinite translation surface, and we show that this surface admits a deformation into other surfaces with topologically equivalent affine symmetries.

X. F. Qian, J. H. Eberly

We formulate the classical polarization theory for light by using entanglement analysis. We demonstrate a route to a systematic and consistent measure of ordinary light polarization that extends automatically to a new understanding of the degree of polarization at a point, when a distinct beam direction is absent. We have drawn on recent work [Qian and Eberl

A. Pathak, A. C. Pradhan, N. V. Sujatha, Jayant Murthy

We present a survey of interstellar O VI absorption in the Large Magellanic Cloud (LMC) towards 70 lines of sight based on Far Ultraviolet Spectroscopic Explorer (FUSE) observations. The survey covers O VI absorption in a large number of objects in different environmental conditions of the LMC. Overall, a high abundance of O VI is present in active and inact

Arie Israel

For a finite $E \subset \R^2$, $f:E \rightarrow \R$, and $p>2$, we produce a continuous $F:\R^2 \rightarrow \R$ depending linearly on $f$, taking the same values as $f$ on $E$, and with $L^{2,p}(\R^2)$ semi-norm minimal up to a factor $C=C(p)$. This solves the Whitney extension problem for the Sobolev space $L^{2,p}(\R^2)$. A standard method for solving exte

Krishnendu Chatterjee, Thomas A. Henzinger, Vinayak S. Prabhu

We consider two-player games played in real time on game structures with clocks where the objectives of players are described using parity conditions. The games are \emph{concurrent} in that at each turn, both players independently propose a time delay and an action, and the action with the shorter delay is chosen. To prevent a player from winning by blockin

Stephane Ross, Geoffrey J. Gordon, J. Andrew Bagnell

Sequential prediction problems such as imitation learning, where future observations depend on previous predictions (actions), violate the common i.i.d. assumptions made in statistical learning. This leads to poor performance in theory and often in practice. Some recent approaches provide stronger guarantees in this setting, but remain somewhat unsatisfactor

Antti Käenmäki, Tapio Rajala, Ville Suomala

Working on doubling metric spaces, we construct generalised dyadic cubes adapting ultrametric structure. If the space is complete, then the existence of such cubes and the mass distribution principle lead into a simple proof for the existence of doubling measures. As an application, we show that for each $ε>0$ there is a doubling measure having full measure

L. A. Harland-Lang, V. A. Khoze, M. G. Ryskin, W. J. Stirling

We study the Central Exclusive Production (CEP) of chi_cJ and eta_c mesons at RHIC in proton-proton collisions. We consider the chi_cJ --> J/psi + gamma decay channels and, recalling that the J_z=0 suppression of the J=1,2 states can be compensated by their larger branchings to J/psi + gamma, present predictions of rates and distributions for chi_c(0,1,2) pr

Eric Opdam, Maarten Solleveld

Let $π, π&#39;$ be tempered representations of an affine Hecke algebra with positive parameters. We study their Euler--Poincaré pairing $EP (π,π&#39;)$, the alternating sum of the dimensions of the Ext-groups. We show that $EP (π,π&#39;)$ can be expressed in a simple formula involving an analytic R-group, analogous to a formula of Arthur in the setting of re

Ahmad Sheykhi, Seyed Hossein Hendi

A possible source of black hole entropy could be the entanglement of quantum fields in and out the horizon. The entanglement entropy of the ground state obeys the area law. However, a correction term proportional to a fractional power of area results when the field is in a superposition of ground and excited states. Inspired by the power-law corrections to e

Vicenç Gómez, Hilbert J. Kappen, Andreas Kaltenbrunner

We analyze the structure and evolution of discussion cascades in four popular websites: Slashdot, Barrapunto, Meneame and Wikipedia. Despite the big heterogeneities between these sites, a preferential attachment (PA) model with bias to the root can capture the temporal evolution of the observed trees and many of their statistical properties, namely, probabil

Yuri Lima, Carlos Gustavo Moreira

We propose a counting dimension for subsets of Z and prove that, under certain conditions on two such subsets E and F, for Lebesgue almost every real \lambda\ the counting dimension of E+[\lambda F] is at least the minimum between 1 and the sum of the counting dimensions of E and F. Furthermore, if the sum of the counting dimensions of E and F is larger than

Robert Rosenbaum, Jianfu Ma, Fabien Marpeau, Aditya Barua

We consider a pair of stochastic integrate and fire neurons receiving correlated stochastic inputs. The evolution of this system can be described by the corresponding Fokker-Planck equation with non-trivial boundary conditions resulting from the refractory period and firing threshold. We propose a finite volume method that is orders of magnitude faster than

Massimiliano Rinaldi

Several alternative ways to quantize gravitational interactions seem to indicate that gravity at short distances is effectively two-dimensional. If this were true, and the energy scale at which the dimensional transition occurs is of the order of the inflationary one, it is reasonable to investigate eventual signatures in the primordial perturbation spectra.

Roc Alabern, Joan Mateu, Joan Verdera

In this paper we present a new characterization of Sobolev spaces on Euclidian spaces ($\mathbb{R}^n$). Our characterizing condition is obtained via a quadratic multiscale expression which exploits the particular symmetry properties of Euclidean space. An interesting feature of our condition is that depends only on the metric of $\mathbb{R}^n$ and the Lebesg

H. B. Benaoum

Global fits to neutrino oscillation data are compatible with tri-bimaximal mixing pattern, which predicts $θ_{23} = \fracπ{4}, θ_{12} = \sin^{-1} (\frac{1}{\sqrt{3}})$ and $θ_{13} = 0$. We propose here to parametrize the tri-bimaximal mixing matrix $V_{TBM}$ by its hermitian generator $H_{TBM}$ using the exponential map. Then we use the exponential map to ex

L. L. Jenkovszky, O. E. Kuprash, J. W. Lamsa, V. K. Magas

A dual-Regge model with a nonlinear proton Regge trajectory in the missing mass channel, describing the experimental data on low-mass single diffraction dissociation, is constructed. Predictions for the LHC energies are given.