June 2013 arXiv papers — page 42

Vadym Kliuchnikov

We describe a new method for approximating an arbitrary $n$ qubit unitary with precision $\varepsilon$ using a Clifford and T circuit with $O(4^{n}n(\log(1/\varepsilon)+n))$ gates. The method is based on rounding off a unitary to a unitary over the ring $\mathbb{Z}[i,1/\sqrt{2}]$ and employing exact synthesis. We also show that any $n$ qubit unitary over the

Florian Rabe

The MMT language has been developed as a scalable representation and interchange language for formal mathematical knowledge. It permits natural representations of the syntax and semantics of virtually all declarative languages while making MMT-based MKM services easy to implement. It is foundationally unconstrained and can be instantiated with specific forma

Michael Kohlhase, Felix Mance, Florian Rabe

Broadly speaking, there are two kinds of semantics-aware assistant systems for mathematics: proof assistants express the semantic in logic and emphasize deduction, and computer algebra systems express the semantics in programming languages and emphasize computation. Combining the complementary strengths of both approaches while mending their complementary we

A. Mironov, A. Morozov, An. Morozov

We consider braids with repeating patterns inside arbitrary knots which provides a multi-parametric family of knots, depending on the "evolution" parameter, which controls the number of repetitions. The dependence of knot (super)polynomials on such evolution parameters is very easy to find. We apply this evolution method to study of the families of k

Klaas Pieter Hart, Leon Luo, Jan van Mill

We show that every space that is the union of a `small' family consisting of special P-sets that are F-spaces, is an F-space. We also comment on the sharpness of our results.

B. Barrios, E. Colorado, R. Servadei, F. Soria

In this work we study the following fractional critical problem $$ (P_λ)=\left\{\begin{array}{ll} (-Δ)^s u=λu^{q} + u^{2^*_{s}-1}, \quad u{>}0 & \mbox{in} Ω\\ u=0 & \mbox{in} \RR^n\setminus Ω\,, \end{array}\right. $$ where $Ω\subset \mathbb{R}^n$ is a regular bounded domain, $λ>0$, $0<s<1$ and $n>2s$. Here $(-Δ)^s$ denotes the fractional Laplace operator def

Hao Guo, Yan He, Chih-Chun Chien, K. Levin

We present a theoretical study of the compressibility, $κ$, in a Fermi gas with attractive contact interactions, providing predictions for the strongly-attractive regime and the superfluid phase. Our work emphasizes the compressibility sum rule and gauge invariance as constraints on $κ$ and we show how within a particular $t$-matrix approach, these can be sa

Janusz Grabowski, Alberto Ibort, Marek Kuś, Giuseppe Marmo

We give a general solution to the question when the convex hulls of orbits of quantum states on a finite-dimensional Hilbert space under unitary actions of a compact group have a non-empty interior in the surrounding space of all density states. The same approach can be applied to study convex combinations of quantum channels. The importance of both problems

H. E. S. S. Collaboration, A. Abramowski, F. Acero, F. Aharonian

A deep observation campaign carried out by the High Energy Stereoscopic System (H.E.S.S.) on Centaurus A enabled the discovery of gamma rays from the blazar 1ES 1312-423, two degrees away from the radio galaxy. With a differential flux at 1 TeV of (1.9 +/-0.6(stat) +/-0.4(sys)) x 10^{-13} /cm^2 /s /TeV corresponding to 0.5% of the Crab nebula differential fl

Frederik J. Simons, Alain Plattner

It is a well-known fact that mathematical functions that are timelimited (or spacelimited) cannot be simultaneously bandlimited (in frequency). Yet the finite precision of measurement and computation unavoidably bandlimits our observation and modeling scientific data, and we often only have access to, or are only interested in, a study area that is temporall

V. N. Chernega, O. V. Man&#39;ko, V. I. Man&#39;ko

New inequalities for tomographic probability distributions and density matrices of qutrit states are obtained by means of generalization of qubit portrait method. The approach based on the qudit portrait method to get new entropic inequalities is proposed. It can be applied to the case of arbutrary nonnegative hermitian matrices including the density matrice

Yixin Cao

We study the \emph{interval completion} problem, which asks for the insertion of a set of at most $k$ edges to make a graph of $n$ vertices into an interval graph. We focus on chordal graphs with no small obstructions, where every remaining obstruction is known to have a shallow property. From such a shallow obstruction we single out a subset 6 or 7 vertices

Aschwanden, M. J., Wuelser, J. P.

We generated an event catalog with an automated detection algorithm based on the entire EUVI image database observed with the two Solar Terrestrial Relations Observatory STEREO-A and -B spacecraft over the first six years of the mission (2006\,--\,2012). The event catalog includes the heliographic positions of some 20\,000 EUV events, transformed from spacec

Vasilios A. Siris, Dimitrios Kalyvas

We present procedures that exploit mobility prediction and prefetching to enhance offloading of traffic from mobile networks to WiFi hotspots, for both delay tolerant and delay sensitive traffic. We evaluate the procedures in terms of the percentage of offloaded traffic, the data transfer delay, and the cache size used for prefetching. The evaluation conside

A. Shemyakin, L. R. Prost

The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters a

Luiz G. A. Alves, Haroldo V. Ribeiro, Ervin K. Lenzi, Renio S. Mendes

We report on a quantitative analysis of relationships between the number of homicides, population size and other ten urban metrics. By using data from Brazilian cities, we show that well defined average scaling laws with the population size emerge when investigating the relations between population and number of homicides as well as population and urban metr

Tiancheng Li, Shudong Sun, Tariq Pervez Sattar

This letter provides an adaptive resampling method. It determines the number of particles to resample so that the Kullback-Leibler distance (KLD) between distribution of particles before resampling and after resampling does not exceed a pre-specified error bound. The basis of the method is the same as Fox&#39;s KLD-sampling but implemented differently. The K

José L. Estévez

This note is about the geometry of the pants graph P(S), a natural simplicial graph associated to a finite type topological surface S where vertices represents pants decompositions. The main result in this note ascserts that for a multicurve Q whose complement is a number of subsurfaces of complexity at most 1. We prove that the corresponding subgraph P(Q) i

Thomas Engl, Julien Dujardin, Arturo Argüelles, Peter Schlagheck

We predict a generic manifestation of quantum interference in many-body bosonic systems resulting in a coherent enhancement of the average return probability in Fock space. This enhancement is both robust with respect to variations of external parameters and genuinely quantum insofar as it cannot be described within mean-field approaches. As a direct manifes

Carlos E. Fiore, Mário J. de Oliveira

It has been proposed (Phys. Rev. E {\bf 71}, 026121 (2005)) that unlike the short range contact process, a long-range counterpart may lead to the existence a discontinuous phase transition in one dimension. Aiming at exploring such link, here we investigate thoroughly a family of long-range contact processes. They are introduced through the transition rate $

Christopher Griffin, George Kesidis, Panayotis Antoniadis, Serge Fdida

Despite its existing incentives for leecher cooperation, BitTorrent file sharing fundamentally relies on the presence of seeder peers. Seeder peers essentially operate outside the BitTorrent incentives, with two caveats: slow downlinks lead to increased numbers of &#34;temporary&#34; seeders (who left their console, but will terminate their seeder role when

Claude E. Mack, Jian Ge, Rohit Deshpande, John P. Wisniewski

We report the discovery of a highly eccentric, double-lined spectroscopic binary star system (TYC 3010-1494-1), comprising two solar-type stars that we had initially identified as a single star with a brown dwarf companion. At the moderate resolving power of the MARVELS spectrograph and the spectrographs used for subsequent radial-velocity (RV) measurements

Aleksi Suutarinen, Lauri K. Haikala, Jorma Harju, Mika Juvela

(abridged) We correlated near-infrared stellar H-Ks colour excesses of background stars from NTT/SOFI with the far-IR optical depth map, tauFIR, derived from Herschel 160, 250, 350, and 500 um data. The Herschel maps were also used to construct a model for the cloud to examine the effect of temperature gradients on the estimated optical depths and dust absor

A. Ozpineci, C. W. Xiao, E. Oset

Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty and obtain several new states. Both I=0 and I=1 states are analyzed and it is shown that in the I=1 sector, the interactions are too weak to create any bound states within

M. M. Voronov, A. B. Pevtsov, S. A. Yakovlev, D. A. Kurdyukov

The results of spectroscopic studies of the diffraction anomalies (the so-called resonant Wood anomalies) in spatially-periodic hybrid structures based on halcogenide (GST225)-coated opal films of various thickness are presented. A theoretical analysis of spectral-angular dependencies of the Wood anomalies has been made by means of a phenomenological approac

Christie S. Nelson, Leonard N. Bezmaternykh, Irina A. Gudim

We report the low-temperature coexistence in NdFe3(BO3)4 of an incommensurate magnetic phase with a strained commensurate magnetic phase that is primarily at the surface of the crystal. Increasing the temperature or magnetic field decreases the incommensurability and stabilizes the commensurate magnetic phase above Tic ~14 K or Hic = 0.9 T. A comparison to p

Nguyen Trung Thành, Larisa Beilina, Michael V. Klibanov, Michael A. Fiddy

The problem to be studied in this work is within the context of coefficient identification problems for the wave equation. More precisely, we consider the problem of reconstruction of the refractive index (or equivalently, the dielectric constant) of an inhomogeneous medium using one backscattering boundary measurement. The goal of this paper is to analyze t

S. Jeyakumar, D. Anish Roshi

We model Carbon Recombination Line (CRL) emission from the Photo Dissociation Region (PDR) surrounding the Ultra-Compact (UC) HII region W48A. Our modelling shows that the inner regions ($A_V \sim 1$) of the CII layer in the PDR contribute significantly to the CRL emission. The dependence of line ratios of CRL emission with the density of the PDR and the far

Ivan Cherednik, Evgeny Feigin

Given a reduced irreducible root system, the corresponding nil-DAHA is used to calculate the extremal coefficients of nonsymmetric Macdonald polynomials, also called E-polynomails, in the limit t=infinity and for antidominant weights, which is an important ingredient of the new theory of nonsymmetric q-Whittaker function. These coefficients are pure q-powers

Eric Akkermans, Thierry Bodineau, Bernard Derrida, Ohad Shpielberg

We show, using the macroscopic fluctuation theory of Bertini, De Sole, Gabrielli, Jona-Lasinio, and Landim, that the statistics of the current of the symmetric simple exclusion process (SSEP) connected to two reservoirs are the same on an arbitrary large finite domain in dimension $d$ as in the one dimensional case. Numerical results on squares support this

Guram Bezhanishvili, Vincenzo Marra, Patrick J. Morandi, Bruce Olberding

A Boolean power S of a commutative ring R has the structure of a commutative R-algebra, and with respect to this structure, each element of S can be written uniquely as an R-linear combination of orthogonal idempotents so that the sum of the idempotents is 1 and their coefficients are distinct. In order to formalize this decomposition property, we introduce

C. R. Allton, P. W. M. Evans, J. -I. Skullerud

The charmonium states at non-zero temperature are studied on anisotropic lattices with 2 dynamical quark flavours. Non-local operators are used to determine the Nambu-Bethe-Salpeter (NBS) wavefunctions via both conventional fitting methods and the Maximum Entropy Method. The interquark potential is determined from the solution of the Schrodinger equation, gi

V. Krasnenko, M. G. Brik

The structural, electronic, and elastic properties of three mixed transition metal carbonitrides TiNxC1-x, ZrNxC1-x, and HfNxC1-x (0<x<1) with the rock-salt structure were calculated at ambient and elevated up to 50 GPa hydrostatic pressures in the framework of the density functional theory methods. The lattice constants, densities, and bulk moduli of the co

Wolfgang von Glasow, Martin Krause, Jesper Sommer-Larsen, Andreas Burkert

We perform hydrodynamical simulations of a young galactic disc embedded in a hot gaseous halo using parameters typical for Lyman break galaxies (LBGs). We take into account the (static) gravitational potentials due to a dark matter halo, a stellar bulge and a disc of stars and gas. Star formation is treated by a local Kennicutt-Schmidt law. We simplify the s

Sanjay Prabhakar, Roderick Melnik, Luis L. Bonilla

In symmetric quantum dots (QDs), it is well known that the spin-hot spot (i.e., the cusp-like structure due to the presence of degeneracy near the level or anticrossing point) is present for the pure Rashba case but is absent for the pure Dresselhaus case [Phys. Rev. Lett. 95, 076805 (2005)]. Since the Dresselhaus spin-orbit coupling dominates over the Rashb

Paul S. Hardersen, K. S. Balasubramaniam, Svetlana Shkolyar

This work utilizes Improved Solar Observing Optical Network (ISOON: Neidig et al. 2003) continuum (630.2 nm) and Hα (656.2 nm) data to: 1) detect and measure intrinsic sunspot rotations occurring in the photosphere and chromosphere, 2) identify and measure chromospheric filament mass motions, and 3) assess any large-scale photospheric and chromospheric mass

Benjamin Scharf

A rather tricky question is the construction of wavelet bases on domains for suitable function spaces (Sobolev, Besov, Triebel-Lizorkin type). In his monograph from 2008, Triebel presented an approach how to construct wavelet (Riesz) bases in function spaces of Besov and Triebel-Lizorkin type on cellular domains, in particular on the cube. However, he had to

R. P. Malik

We derive the off-shell nilpotent Becchi-Rouet-Stora-Tyutin (BRST), anti-BRST, (anti-)co-BRST, a bosonic and the ghost-scale symmetry transformations for a couple of equivalent Lagrangian densities of the two (1 + 1)-dimensional (2D) Stueckelberg-modified version of Proca theory which also incorporates a pseudo-scalar field. We also discuss algebraically sui

Karsten Buesser

The International Linear Collider (ILC) is a proposed electron-positron collider for the centre-of-mass energy range of 200 to 500 GeV and with upgrade options towards 1 TeV. The ILC would be the ideal tool to explore with high precision the properties of the new Higgs-like particle that has recently been discovered at the LHC with a mass of around 125 GeV.

M. A. L. Capri, D. Dudal, M. S. Guimaraes, I. F. Justo

An all orders algebraic proof of the multiplicative renormalizability of the novel formulation of the Gribov-Zwanziger action proposed in Phys. Rev. D 86, 045005 (2012) [arXiv:1205.3934], and allowing for an exact but spontaneously broken BRST symmetry, is provided.

Newton da Costa, Christian de Ronde

Physical superpositions exist both in classical and in quantum physics. However, what is exactly meant by &#39;superposition&#39; in each case is extremely different. In this paper we discuss some of the multiple interpretations which exist in the literature regarding superpositions in quantum mechanics. We argue that all these interpretations have something

Peter Hellekalek

The starting point of this paper is the interplay between the construction principle of a sequence and the characters of the compact abelian group that underlies the construction. In case of the Halton sequence in base $\mathbf b=(b_1, \ldots, b_s)$ in the $s$-dimensional unit cube $[0,1)^s$, which is an important type of a digital sequence, this kind of dua

Samuel Fiorini, Kanstantsin Pashkovich

An extended formulation of a polytope is a linear description of this polytope using extra variables besides the variables in which the polytope is defined. The interest of extended formulations is due to the fact that many interesting polytopes have extended formulations with a lot fewer inequalities than any linear description in the original space. This m

Marc Green, Justin Hess, Tom Lacroix, Jordan Marchetto

In this paper we put forward a proposal to use Near Earth Objects as radiation shield for deep space exploration. In principle these objects can provide also a spacious habitat for the astronauts and their supplies on their journeys. We undertake also a detailed assessment of this proposal for a mission from Earth to Mars.

Chris Wymant

This doctoral thesis addresses aspects of Supersymmetry (Susy) phenomenology. In addition to previously published work, it contains introductions to the following topics: from classical mechanics to quantum field theory for the more casual reader, electroweak naturalness, the Higgs as a pseudo-Nambu-Goldstone boson, the MSSM and NMSSM, simple and less simple

Baolin Tan

A peculiar microwave quasi-periodic pulsation with zigzag pattern (Z-QPP) is observed first by the Chinese Solar Broadband Spectrometer in Huairou (SBRS/Huairou) at 1.10-1.34 GHz in a solar flare on 2005-01-15. The Z-QPP occurred just in the early rising phase of the flare with weakly right-handed circular polarization. Its period is only several decades mil

Chloé Guennou, Frédéric Auchère, James A. Klimchuk, Karine Bocchialini

In this paper, the ability of the Hinode/EIS instrument to detect radiative signatures of coronal heating is investigated. Recent observational studies of AR cores suggest that both the low and high frequency heating mechanisms are consistent with observations. Distinguishing between these possibilities is important for identifying the physical mechanism(s)

J. Mendil, P. C. Nieves, O. Chubykalo-Fesenko, J. Walowski

Magnetization manipulation is becoming an indispensable tool for both basic and applied research. Theory predicts two types of ultrafast demagnetization dynamics classified as type I and type II. In type II materials, a second slower process takes place after the initial fast drop of magnetization. In this letter we investigate this behavior for FePt recordi

John Jasper, Dustin G. Mixon, Matthew Fickus

An equiangular tight frame (ETF) is a set of unit vectors in a Euclidean space whose coherence is as small as possible, equaling the Welch bound. Also known as Welch-bound-equality sequences, such frames arise in various applications, such as waveform design and compressed sensing. At the moment, there are only two known flexible methods for constructing ETF

Rémy Chicheportiche, Jean-Philippe Bouchaud

Many problems in finance are related to first passage times. Among all of them, we chose three on which we contributed personally. Our first example relates Kolmogorov-Smirnov like goodness-of-fit tests, modified in such a way that tail events and core events contribute equally to the test (in the standard Kolmogorov-Smirnov, the tails contribute very little

A. Lindmaa, R. Lizárraga, E. Holmström, I. A. Abrikosov

We present a first principles supercell methodology for the calculation of exchange interactions of magnetic materials with arbitrary degrees of structural and chemical disorder in their high temperature paramagnetic state. It is based on a projection of the total magnetic energy of the system onto local pair clusters, allowing the interactions to vary indep

Xiaofeng Luo

We present various order moments (Variance ($σ^2$), Skewness($S$), Kurtosis($κ$)) of net-proton multiplicity distributions in Au+Au collisions from the first phase of RHIC beam energy scan ({\sNN}=7.7$-$200 GeV). The measurements are carried out by the STAR detector at mid-rapidity ($|y|<0.5$) and within transverse momentum range $0.4<p_{T}<0.8$ {\gevc}. The

R. Kale, T. Venturi, S. Giacintucci, D. Dallacasa

A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo Survey (GRHS, Venturi et al. 2007, 2008). It is a systematic radio survey of galaxy clusters selected from the REFLEX and eBCS X

J. M. F. Donnert

We review models for giant radio halos in clusters of galaxies, with a focus on numerical and theoretical work. After summarising the most important observations of these objects, we present an introduction to the theoretical aspects of hadronic models. We compare these models with observations using simulations and find severe problems for hadronic models.

Kodai Yamamoto, Taro Matsuo, Hiroshi Shibai, Yoichi Itoh

We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the $H$ and $K_{S}$ bands using HiCIAO combined with the adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the $H$ band around 9 stars. Five of these 13 were confirmed to be background stars by mea

S. Bautista, C. A. Morales

We prove that every sectional-Anosov flow of a compact 3-manifold $M$ exhibits a finite collection of hyperbolic attractors and singularities whose basins form a dense subset of $M$. Applications to the dynamics of sectional-Anosov flows on compact 3-manifolds include a characterization of essential hyperbolicity, sensitivity to the initial conditions (impro

Silvestre Abruzzo, Hermann Kampermann, Dagmar Bruß

We generalize measurement-device-independent quantum key distribution [ H.-K. Lo, M. Curty, and B. Qi, Phys. Rev. Lett. 108, 130503 (2012) ] to the scenario where the Bell-state measurement station contains also heralded quantum memories. We find analytical formulas, in terms of device imperfections, for all quantities entering in the secret key rates, i.e.,

V. M. Kolomietz, A. I. Sanzhur

We redefine the surface tension coefficient and the symmetry energy for an asymmetric nuclear Fermi-liquid drop with a finite diffuse layer. Considering two-component charged Fermi-liquid drop and following Gibbs-Tolman concept, we introduce the equimolar radius $R_{e}$ of sharp surface droplet at which the surface tension is applied and the radius of tensio

A. F. Garcia, M. B. Pinto

The surface tension of quark matter plays a crucial role for the possibility of quark matter nucleation during the formation of compact stellar objects and also for the existence of a mixed phase within hybrid stars. However, despite its importance, this quantity does not have a well established numerical value. Some early estimates have predicted that, at z

Tsunenori Inakura, Takashi Nakatsukasa, Kazuhiro Yabana

Correlations between low-lying electric dipole (E1) strength and neutron skin thickness are systematically investigated with the fully self-consistent random-phase approximation using the Skyrme energy functionals. The presence of strong correlation among these quantities is currently under dispute. We find that the strong correlation is present in properly

Jonas Hägglund, Klas Markstrøm

In this paper we show that many snarks have shortest cycle covers of length $\frac{4}{3}m+c$ for a constant $c$, where $m$ is the number of edges in the graph, in agreement with the conjecture that all snarks have shortest cycle covers of length $\frac{4}{3}m+o(m)$. In particular we prove that graphs with perfect matching index at most 4 have cycle covers of

Montserrat Casals-Ruiz, Andrew Duncan, Ilya Kazachkov

In this note we give two examples of partially commutative subgroups of partially commutative groups. Our examples are counterexamples to the Extension Graph Conjecture and to the Weakly Chordal Conjecture of Kim and Koberda, \cite{KK}. On the other hand we extend the class of partially commutative groups for which it is known that the Extension Graph Conjec

Jorge Hernandez, Beatriz Marcotegui

Dans cet article, nous présentons une méthode pour la détection et la classification d&#39;artefacts au niveau du sol, comme phase de filtrage préalable à la modélisation d&#39;environnements urbains. La méthode de détection est réalisée sur l&#39;image profondeur, une projection de nuage de points sur un plan image où la valeur du pixel correspond à la dist

Mélanie Noyel, Philippe Thomas, Patrick Charpentier, André Thomas

Product quality level is become a key factor for companies&#39; competitiveness. A lot of time and money are required to ensure and guaranty it. Besides, motivated by the need of traceability, collecting production data is now commonplace in most companies. Our paper aims to show that we can ensure the required quality thanks to an &#34;on-line quality appro

Mahan Mj, Caroline Series

We show that for a strongly convergent sequence of purely loxodromic finitely generated Kleinian groups with incompressible ends, Cannon-Thurston maps, viewed as maps from a fixed base limit set to the Riemann sphere, converge uniformly. For algebraically convergent sequences we show that there exist examples where even pointwise convergence of Cannon-Thurst

Emmanuel Frenod, Sever Adrian Hirstoaga, Eric Sonnendrücker

In the framework of a Particle-In-Cell scheme for some 1D Vlasov-Poisson system depending on a small parameter, we propose a time-stepping method which is numerically uniformly accurate when the parameter goes to zero. Based on an exponential time differencing approach, the scheme is able to use large time steps with respect to the typical size of the fast o

Linjie Xiong, Tao Wang, Lusheng Wang

The Cauchy problem to the Fokker-Planck-Boltzmann equation under Grad&#39;s angular cut-off assumption is investigated. When the initial data is a small perturbation of an equilibrium state, global existence and optimal temporal decay estimates of classical solutions are established. Our analysis is based on the coercivity of the Fokker-Planck operator and a

Heiko Füser, Mark Bieler

We demonstrate optical coherent control of the emission direction of THz radiation. Femtosecond laser pulses are used to excite different types of ultrafast photocurrents along different directions in a bulk GaAs sample. The overall emission pattern can be modified by changing the phase of the optical excitation. With this method, THz beam steering of about

Andreas Doering

We discuss some conceptual issues that any approach to quantum gravity has to confront. In particular, it is argued that one has to find a theory that can be interpreted in a realist manner, because theories with an instrumentalist interpretation are problematic for several well-known reasons. Since the Hilbert space formalism almost inevitably forces an ins

Gert Aarts, Pietro Giudice, Erhard Seiler

Complex Langevin dynamics can solve the sign problem appearing in numerical simulations of theories with a complex action. In order to justify the procedure, it is important to understand the properties of the real and positive distribution, which is effectively sampled during the stochastic process. In the context of a simple model, we study this distributi

Thomas-Paul Hack

In the standard model of cosmology, the universe is described by a Robertson-Walker spacetime, while its matter/energy content is modeled by a perfect fluid with three components corresponding to matter/dust, radiation and a cosmological constant. On the other hand, in particle physics matter and radiation are described in terms of quantum field theory on Mi

Michal Stanislaw Wojcik

The main result of this paper states that for a function $f:\R^2\to Y$ with a closed, connected and locally connected graph, where $Y$ is a locally compact, second-countable metrisable space, the graph over discontinuity points remains locally connected.

Walter H. Aschbacher

Using the framework of rigorous algebraic quantum statistical mechanics, we construct the unique nonequilibrium steady state in the isotropic XY chain in which a sample of arbitrary finite size is coupled by a bond coupling perturbation of arbitrary strength to two infinitely extended thermal reservoirs, and we prove that this state is thermodynamically nont

Robert Ekblom, Dennis Hasselquist, Stein Are S{\Ae}Ther, Peder Fiske

1. In recent years many studies have investigated the relationships between different aspects of the immune system and ecology in various organisms. Yet, it remains unclear why individuals differ in their ability to mount an immune response against various antigens (often referred to as &#39;immunocompetence&#39;). Different kinds of trade-offs may be involv

Matthew England

Cylindrical algebraic decomposition (CAD) is an important tool for the investigation of semi-algebraic sets, with applications within algebraic geometry and beyond. We recently reported on a new implementation of CAD in Maple which implemented the original algorithm of Collins and the subsequent improvement to projection by McCallum. Our implementation was i

Gašper Tkačik, Olivier Marre, Dario Amodei, Elad Schneidman

Maximum entropy models are the least structured probability distributions that exactly reproduce a chosen set of statistics measured in an interacting network. Here we use this principle to construct probabilistic models which describe the correlated spiking activity of populations of up to 120 neurons in the salamander retina as it responds to natural movie

Sébastien Paris, Yann Doh, Hervé Glotin, Xanadu Halkias

This paper presents a spermwhale&#39; localization architecture using jointly a bag-of-features (BoF) approach and machine learning framework. BoF methods are known, especially in computer vision, to produce from a collection of local features a global representation invariant to principal signal transformations. Our idea is to regress supervisely from these

D. S. Gonçalves, M. A. Gomes-Ruggiero, C. Lavor

In this paper we present an inexact stepsize selection for the Diluted RρR algorithm, used to obtain the maximum likelihood estimate to the density matrix in quantum state tomography. We give a new interpretation for the diluted RρR iterations that allows us to prove the global convergence under weaker assumptions. Thus, we propose a new algorithm which is g

Haichang Gao, Xiuling Chang, Zhongjie Ren, Uwe Aickelin

Graphical passwords have been proposed as an alternative to alphanumeric passwords with their advantages in usability and security. However, they still tend to follow predictable patterns that are easier for attackers to exploit, probably due to users&#39; memory limitations. Various literatures show that baroque music has positive effects on human learning

Haichang Gao, Zhongjie Ren, Xiuling Chang, Xiyang Liu

Graphical passwords have been demonstrated to be the possible alternatives to traditional alphanumeric passwords. However, they still tend to follow predictable patterns that are easier to attack. The crux of the problem is users&#39; memory limitations. Users are the weakest link in password authentication mechanism. It shows that baroque music has positive

Laurent Battisti, Karl Oeljeklaus

In this paper we extend results due to Vogt on line bundles over Cousin groups to the case of domains stable by the maximal compact subgroup. This is used in the sequel to show that the algebraic dimension of OT-manifolds is zero. In the last part we establish that certain Cousin groups, in particular those arising from the construction of OT-manifolds, have

Jun Pei, Chengming Bai, Li Guo

This paper establishes a uniform procedure to split the operations in any algebraic operad, generalizing previous known notions of splitting algebraic structures from the dendriform algebra of Loday that splits the associative operation to the successors that split any binary operad. Examples are provided for various $n$-associative algebras, $n$-Lie algebra

Gregory Faye, Arnd Scheel

We establish Fredholm properties for a class of nonlocal differential operators. Using mild convergence and localization conditions on the nonlocal terms, we also show how to compute Fredholm indices via a generalized spectral flow, using crossing numbers of generalized spatial eigenvalues. We illustrate possible applications of the results in a nonlinear an

E. V. Pitjeva, N. P. Pitjev

The high precision of the latest version of the planetary ephemeris EPM2011 enables one to explore more accurately a variety of small effects in the solar system. The processing of about 678 thousand of position observations of planets and spacecrafts for 1913--2011 with the predominance of modern radar measurements resulted in improving the PPN parameters,

J. A. Galvis, H. Suderow, S. Vieira, S. L. Bud&#39;ko

We present very low temperature (0.15 K) scanning tunneling microscopy and spectroscopy experiments in the layered superconductor LaSb$_2$. We obtain topographic microscopy images with surfaces showing hexagonal and square atomic size patterns, and observe in the tunneling conductance a superconducting gap. We find well defined quasiparticle peaks located at

M. I. Belishev, M. N. Demchenko

We deal with two dynamical systems associated with a Riemannian manifold with boundary. The first one is a system governed by the scalar wave equation, the second is governed by the Maxwell equations. Both of the systems are controlled from the boundary. The inverse problem is to recover the manifold via the relevant measurements at the boundary (inverse dat

David Aldous

Persi Diaconis was born in New York on January 31, 1945. Upon receiving a Ph.D. from Harvard in 1974 he was appointed Assistant Professor at Stanford. Following periods as Professor at Harvard (1987-1997) and Cornell (1996-1998), he has been Professor in the Departments of Mathematics and Statistics at Stanford since 1998. He is a member of the National Acad

Reza Torabi, Zahra Rezaei

We study acoustic vortex in media with screw dislocation using the Katanaev-Volovich theory of defects. It is shown that the screw dislocation affects the beam&#39;s orbital angular momentum and changes the acoustic vortex strength. This change is a manifestation of topological Dirac phase and is robust against fluctuations in the system.

Saeed Afshar, Gregory Cohen, Runchun Wang, Andre van Schaik

In this paper we present the biologically inspired Ripple Pond Network (RPN), a simply connected spiking neural network that, operating together with recently proposed PolyChronous Networks (PCN), enables rapid, unsupervised, scale and rotation invariant object recognition using efficient spatio-temporal spike coding. The RPN has been developed as a hardware

P. Paykari, S. Pires, J. -L. Starck, A. H. Jaffe

The next generation of galaxy surveys, aiming to observe millions of galaxies, are expensive both in time and cost. This raises questions regarding the optimal investment of this time and money for future surveys. In a previous work, it was shown that a sparse sampling strategy could be a powerful substitute for the contiguous observations. However, in this

Deepjyoti Goswami

In this article, we discuss a couple of nonlinear Galerkin methods (NLGM) in finite element set up for time dependent incompressible Navier-Sotkes equations. We show the crucial role played by the non-linear term in determining the rate of convergence of the methods. We have obtained improved error estimate in $\bL^2$ norm, which is optimal in nature, for li

Minh-Ngoc Tran, Paolo Giordani, Xiuyan Mun, Robert Kohn

Copulas are popular as models for multivariate dependence because they allow the marginal densities and the joint dependence to be modeled separately. However, they usually require that the transformation from uniform marginals to the marginals of the joint dependence structure is known. This can only be done for a restricted set of copulas, e.g. a normal co

Kazutaka Kurihara, Masakazu Takasu, Kazuhiro Sasao, Hal Seki

This paper demonstrates that face-like structures are everywhere, and can be de-tected automatically even with computers. Huge amount of satellite images of the Earth, the Moon, the Mars are explored and many interesting face-like structure are detected. Throughout this fact, we believe that science and technologies can alert people not to easily become an o

Y. Morino, Y. Nakatsugawa, M. Yosoi, M. Niiyama

We report the measurement of differential cross sections for $ω$ and $η&#39;$ photoproduction from protons at backward angles ($-1.0<\cosΘ_{C.M}^{X}<-0.8$) using linearly polarized photons at $E_γ=$$1.5-3.0$ GeV. Differential cross sections for $ω$ mesons are larger than the predicted $u$-channel contribution in the energy range $2.0\leq\sqrt{s}\leq2.4$ GeV.

P. Garg, D. K. Mishra, P. K. Netrakanti, A. K. Mohanty

An unfolding method, based on Bayes theorem is presented to obtain true event-by-event net-charge multiplicity distribution from a corresponding measured distribution, which is subjected to detector artifacts. The unfolding is demonstrated to work for widely varying particle production mechanism, beam energy and collision centrality. Further the necessity of

Jia-An Lu, Chao-Guang Huang

We construct Kaluza--Klein-type models with a de Sitter or Minkowski bundle in the de Sitter or Poincaré gauge theory of gravity, respectively. A manifestly gauge-invariant formalism has been given. The gravitational dynamics is constructed by the geometry of the de Sitter or Minkowski bundle and a global section which plays an important role in the gauge-in

Fabio Bresolin

The oxygen abundance of the outer disk of the nearby S0 galaxy NGC 404, a prototypical early-type galaxy with extended star formation, has been derived from the analysis of HII region spectra. The high mean value found, 12+log(O/H)=8.6 \pm 0.1, equivalent to approximately 80% of the solar value, argues against both the previously proposed cold accretion and

Ákos Magyar, Tatchai Titichetrakun

Let $\PP^d$ be the $d$-fold direct product of the set of primes. We prove that if $A$ is a subset of $\PP^d$ of positive relative upper density then $A$ contains infinitely many &#34;corners&#34;, that is sets of the form $\{x,x+te_1,...,x+te_d\}$ where x is an integer point and e_1,...,e_d are the standard basis vectors of the d-dimensional Euclidean space.

Kui Jin, Richard Suchoski, Sean Fackler, Yi Zhang

We have fabricated Fe-B thin film composition spreads in search of possible superconducting phases following a theoretical prediction by Kolmogorov et al.^1 Co-sputtering was used to deposit spreads covering a large compositional region of the Fe-B binary phase diagram. A trace of superconducting phase was found in the nanocrystalline part of the spread, whe

P. -H. Dupont, C. Couteau, D. J. Rogers, F. Hosseini Téhérani

Zinc Oxide thin films were grown on c-sapphire substrates using pulsed laser deposition. Pump power dependence of surface emission spectra, acquired using a quadrupled 266 nm laser, revealed room temperature stimulated emission (threshold of 900 kW/cm2). Time dependent spectral analysis plus gain measurements of single-shot, side-emission, spectra pumped wit