June 2011 arXiv papers

Bernard Leikind

Dr. William Bruno asserts the well-known fact that cell phones radiate microwaves in the classical regime. This, he says, means that the photon energy is not relevant to assessing safety. Citing optical tweezers as an example of biologically relevant non-thermal effects of electromagnetic radiation, Bruno concludes that all other reports of non-thermal effec

Patrick L. Combettes, Jean-Christophe Pesquet

We propose a primal-dual splitting algorithm for solving monotone inclusions involving a mixture of sums, linear compositions, and parallel sums of set-valued and Lipschitzian operators. An important feature of the algorithm is that the Lipschitzian operators present in the formulation can be processed individually via explicit steps, while the set-valued op

Feng Jiang, A. Lee Swindlehurst

In this paper we consider a collection of single-antenna ground nodes communicating with a multi-antenna unmanned aerial vehicle (UAV) over a multiple-access ground-to-air wireless communications link. The UAV uses beamforming to mitigate the inter-user interference and achieve spatial division multiple access (SDMA). First, we consider a simple scenario wit

Jean-Philippe Mandallena

Relaxation theorems for multiple integrals on W^{1,p}(Ω;\RR^m), where p\in]1,\infty[, are proved under general conditions on the integrand L:\MM\to[0,\infty] which is Borel measurable and not necessarily finite. We involve a localization principle that we previously used to prove a general lower semicontinuity result. We apply these general results to the re

R. Dascaliuc, Z. Grujić

Existence of 2D enstrophy cascade in a suitable mathematical setting, and under suitable conditions compatible with 2D turbulence phenomenology, is known both in the Fourier and in the physical scales. The goal of this paper is to show that the same geometric condition preventing the formation of singularities - 1/2-Hölder coherence of the vorticity directio

Victor Campos, Cláudia Linhares-Sales, Ana Karolinna Maia, Nicolas Martins

In this paper, we obtain polynomial time algorithms to determine the acyclic chromatic number, the star chromatic number, the Thue chromatic number, the harmonious chromatic number and the clique chromatic number of $P_4$-tidy graphs and $(q,q-4)$-graphs, for every fixed $q$. These classes include cographs, $P_4$-sparse and $P_4$-lite graphs. All these color

N. Roy, G. Gordon, S. Thrun

Standard value function approaches to finding policies for Partially Observable Markov Decision Processes (POMDPs) are generally considered to be intractable for large models. The intractability of these algorithms is to a large extent a consequence of computing an exact, optimal policy over the entire belief space. However, in real-world POMDP problems, com

Omer Friedland, Yosef Yomdin

The main observation of this note is that the Lebesgue measure $μ$ in the Turán-Nazarov inequality for exponential polynomials can be replaced with a certain geometric invariant $ω\ge μ$, which can be effectively estimated in terms of the metric entropy of a set, and may be nonzero for discrete and even finite sets. While the frequencies (the imaginary parts

Guenther Hoermann, Michael Kunzinger, Roland Steinbauer

We consider wave equations on Lorentzian manifolds in case of low regularity. We first extend the classical solution theory to prove global unique solvability of the Cauchy problem for distributional data and right hand side on smooth globally hyperbolic space-times. Then we turn to the case where the metric is non-smooth and present a local as well as a glo

Sam R. Dolan, Barry Wardell, Leor Barack

This is the second in a series of papers aimed at developing a practical time-domain method for self-force calculations in Kerr spacetime. The key elements of the method are (i) removal of a singular part of the perturbation field with a suitable analytic "puncture" based on the Detweiler--Whiting decomposition, (ii) decomposition of the perturbation

Shantanu Dave, Guenther Hoermann, Michael Kunzinger

We investigate regularizations of distributional sections of vector bundles by means of nets of smooth sections that preserve the main regularity properties of the original distributions (singular support, wavefront set, Sobolev regularity). The underlying regularization mechanism is based on functional calculus of elliptic operators with finite speed of pro

Olaf Hohm, Seung Ki Kwak, Barton Zwiebach

We use double field theory to give a unified description of the low energy limits of type IIA and type IIB superstrings. The Ramond-Ramond potentials fit into spinor representations of the duality group O(D,D) and field-strengths are obtained by acting with the Dirac operator on the potentials. The action, supplemented by a Spin^+(D,D)-covariant self-duality

Jun Wen, Mehdi Kargarian, Abolhassan Vaezi, Gregory A. Fiete

We study the Kane-Mele-Hubbard model both at half-filling and away from half-filling using a slave-boson mean-field approach at zero temperature. We obtain a phase diagram at half-filling and discuss its connection to recent results from quantum Monte Carlo, slave-rotor, and $Z_2$ mean-field studies. In particular, we find a small window in parameter space w

Nobuhiro Okabe, Herve Bourdin, Pasquale Mazzotta, Sophie Maurogordato

We present a weak-lensing analysis of the merging cluster A2163 using Subaru/Suprime-Cam and CFHT/Mega-Cam data and discuss the dynamics of this cluster merger, based on complementary weak-lensing, X-ray, and optical spectroscopic datasets. From two dimensional multi-component weak-lensing analysis, we reveal that the cluster mass distribution is well descri

Dimitrie Culcer, A. L. Saraiva, Belita Koiller, Xuedong Hu

We devise a platform for noise-resistant quantum computing using the valley degree of freedom of Si quantum dots. The qubit is encoded in two polarized (1,1) spin-triplet states with different valley compositions in a double quantum dot, with a Zeeman field enabling unambiguous initialization. A top gate gives a difference in the valley splitting between the

Michele Redi, Andreas Weiler

The flavor protection in composite Higgs models with partial compositeness is known to be insufficient. We explore the possibility to alleviate the tension with CP odd observables by assuming that flavor or CP are symmetries of the composite sector, broken by the coupling to Standard Model fields. One realization is that the composite sector has a flavor sym

Bryan W. Lynn

B.W.Lee/K.Symanzik proved that Ward-Takahashi identities and tadpole renormalization force all ultra-violet quadratic divergences (UV-QD) to be absorbed into the physical renormalized pseudo-scalar pion mass in O(4)LSM (linear sigma models) across the Higgs-VEV vs. Pion-Mass-Squared half-plane. We show that all UV-QD vanish identically in the "Goldstone

Sanil Unnikrishnan, Shruti Thakur, T. R. Seshadri

This paper has been withdrawn by the author due to an error in equation 13.

I. C. Fulga, F. Hassler, A. R. Akhmerov

The topological invariant of a topological insulator (or superconductor) is given by the number of symmetry-protected edge states present at the Fermi level. Despite this fact, established expressions for the topological invariant require knowledge of all states below the Fermi energy. Here, we propose a way to calculate the topological invariant employing s

Pradeep Sarvepalli, Pawel Wocjan

Infrastructures are group-like objects that make their appearance in arithmetic geometry in the study of computational problems related to number fields and function fields over finite fields. The most prominent computational tasks of infrastructures are the computation of the circumference of the infrastructure and the generalized discrete logarithms. Both

Joseph Polchinski

A recent paper by Gambini, Rastgoo and Pullin [arXiv:1106.1417 investigates the important issue of constraints from Lorentz invariance on Planck scale physics, arguing that the classic analysis of Collins, Perez, Sudarsky, Urrutia and Vucetich \cite{cpsuv} is not generally valid. We argue that the new work is based on models that do not capture the relevant

Gennady Gorelik

The cultural infrastructure that let Galileo invent the modern physics is discussed. The key new element of modern physics was firm belief in its fundamental structure, which could be expressed in the double postulate: 1) There are fundamental axioms that all the physical laws could be deduced from; those axioms are not evident, as invisible as the undergrou

Ronen Lerner, Oleg Kupervasser, Ehud Rivlin

An algorithm for pose and motion estimation using corresponding features in omnidirectional images and a digital terrain map is proposed. In previous paper, such algorithm for regular camera was considered. Using a Digital Terrain (or Digital Elevation) Map (DTM/DEM) as a global reference enables recovering the absolute position and orientation of the camera

Cecilia Bejarano, Ernesto F. Eiroa

In this article, we construct spherical thin-shell wormholes with charge in dilaton gravity. The exotic matter required for the construction is provided by a generalized Chaplygin gas. We study the stability under perturbations preserving the symmetry. We find that the increase of the coupling between the dilaton and the electromagnetic fields reduces the ra

J. P. Clancy, B. D. Gaulin, A. S. Sefat

We have performed high resolution x-ray scattering measurements on single crystal samples of Ba(Fe(1-x)Cr(x))2As2 (x = 0 to 0.335). These measurements examine the effect of Cr-doping on the high temperature tetragonal (I4/mmm) to low temperature orthorhombic (Fmmm) structural phase transition of the parent compound BaFe2As2. Increasing Cr concentration is fo

Dmitry Karlovets

We reanalyze the problem of radiative polarization of electrons brought into collision with a circularly polarized strong plane wave. We present an independent analytical verification of formulae for the cross section given by D.\,Yu. Ivanov et al [Eur.\ Phys.\ J. C \textbf{36}, 127 (2004)]. By choosing the exact electron's helicity as the spin quantum n

Victor Parkinson, L. H. Ford

A localized charged particle oscillating near a reflecting boundary is considered as a model for non-cancellation of vacuum fluctuations. Although the mean velocity of the particle is sinusoidal, the velocity variance produced by vacuum fluctuation can either grow or decrease linearly in time, depending upon the product of the oscillation frequency and the d

Kostas Glampedakis, Nils Andersson, Samuel K. Lander

Traditionally, the subject of hydromagnetic equilibrium in neutron stars has been addressed in the context of standard magnetohydrodynamics, with matter obeying a barotropic equation of state. In this paper we take a step towards a more realistic treatment of the problem by considering neutron stars with interior superfluid components. In this multifluid mod

Alexander Yu. Cherny, Jean-Sebastien Caux, Joachim Brand

The one-dimensional Bose gas is an unusual superfluid. In contrast to higher spatial dimensions, the existence of non-classical rotational inertia is not directly linked to the dissipationless motion of infinitesimal impurities. Recently, experimental tests with ultracold atoms have begun and quantitative predictions for the drag force experienced by moving

Jeong-woo Cho, Jean-Yves Le Boudec, Yuming Jiang

Performance evaluation of the 802.11 MAC protocol is classically based on the decoupling assumption, which hypothesizes that the backoff processes at different nodes are independent. This decoupling assumption results from mean field convergence and is generally true in transient regime in the asymptotic sense (when the number of wireless nodes tends to infi

Thomas-Paul Hack, Mathias Makedonski

It is well-known that coupling a spin $\frac32$-field to a gravitational or electromagnetic background leads to potential problems both in the classical and in the quantum theory. Various solutions to these problems have been proposed so far, which are all restricted to a limited class of backgrounds. On the other hand, negative results for general gravitati

Amine Benhenni, Jean-Loic Kneur, Gilbert Moultaka, Sean Bailly

We consider no-scale inspired supergravity scenarios, where the gravitino mass and related soft supersymmetry-breaking parameters are determined dynamically by radiative corrections to an essentially flat tree-level potential in the supersymmetry breaking hidden sector. We examine the theoretical and phenomenological viability of such a mechanism, when inclu

S. K. Lander, N. Andersson, K. Glampedakis

We construct two-fluid equilibrium configurations for neutron stars with magnetic fields, using a self-consistent and nonlinear numerical approach. The two-fluid approach - likely to be valid for large regions of all but the youngest NSs - provides us with a straightforward way to introduce stratification and allows for more realistic models than the ubiquit

Violeta Petkova

We study the spectrum of multipliers (bounded operators commuting with the shift operator S) on Banach spaces of sequences on Z and the spectrum of operators commuting with the shift on Banach spaces of sequences on Z^+.We generalize the results for multipliers on Banach spaces of sequences on Z^k.

Letizia Brunetti

A condition of Osserman type, called $ϕ$-null Osserman condition, is introduced and studied in the context of Lorentz globally framed $f$-manifolds. An explicit example shows the naturalness of this condition in the setting of Lorentz $\mathcal{S}$-manifolds. We prove that a Lorentz $\mathcal{S}$-manifold with constant $ϕ$-sectional curvature is $ϕ$-null Oss

Moritz Gerlach, Robin Nittka

We prove that every bounded, positive, irreducible, stochastically continuous semigroup on the space of bounded, measurable functions which is strong Feller, consists of kernel operators and possesses an invariant measure converges pointwise. This differs from Doob's theorem in that we do not require the semigroup to be Markovian and request a fairly wea

Ali Akbar Abolhasani, Hassan Firouzjahi, Misao Sasaki

We investigate the parameter spaces of hybrid inflation model with special attention paid to the dynamics of waterfall field and curvature perturbations induced from its quantum fluctuations. Depending on the inflaton field value at the time of phase transition and the sharpness of the phase transition inflation can have multiple extended stages. We find tha

D. D. Chinellato

The production of charged multi-strange particles is studied with the ALICE experiment at the CERN LHC. Measurements of the central rapidity yields of $Ξ^-$ and $Ω^-$ baryons, as well as their antiparticles, are presented as a function of transverse momentum ($p_\mathrm{t}$) for inelastic pp collisions at $\sqrt{s}=7$ TeV and compared to existing measurement

Jonathan R. Gair, Nicolas Yunes

Extreme-mass-ratio inspirals, in which a stellar-mass compact object spirals into a supermassive black hole, are prime candidates for detection with space-borne milliHertz gravitational wave detectors, similar to the Laser Interferometer Space Antenna. The gravitational waves generated during such inspirals encode information about the background in which th

Jean-Louis Colliot-Thélène, Alexei N. Skorobogatov

For a smooth and projective variety X over a field k of characteristic zero we prove the finiteness of the cokernel of the natural map from the Brauer group of X to the Galois-invariant subgroup of the Brauer group of the same variety over an algebraic closure of k. Under further conditions on k, e.g. over number fields, we give estimates for the order of th

Daniel G. Barci, Paulo S. A. Bonfim

We study the competition between a Pomeranchuk instability in the spin channel with angular momentum $\ell=1$ and an attractive interaction, favoring Cooper-pair formation. We found that the superconducting gap strongly suppresses the phase space for the Pomeranchuk instability. We computed a mean-field phase diagram displaying a first order transition betwe

Guillaume Dreyer

Given a Hitchin representation $ρ\colon π_1(S) \to \PSL_n(\mathbb{R})$, we construct $n$ continuous functions $\ell_i^ρ\colon \mathcal \CH(S) \to \mathbb{R}$ defined on the space of Hölder geodesic currents $\CH(S)$ such that, for a closed, oriented curve $γ$ in $S$, the $i$--th eigenvalue of the matrix $ρ(γ)\in \PSL_n(\mathbb{R})$ is of the form $\pm \mathr

E. Kermarrec, P. Mendels, F. Bert, R. H. Colman

We report muSR experiments on Mg{x}Cu{4-x}(OH)6Cl2 with x \sim 1, a new material isostructural to Herbertsmithite exhibiting regular kagome planes of spin 1/2 (Cu^{2+}), and therefore a candidate for a spin liquid ground state. We evidence the absence of any magnetic ordering down to 20 mK (\sim J/10^4). We investigate in detail the spin dynamics on well cha

Gabi Ben Simon, Tobias Hartnick

We show that a group admits a non-zero homogeneous quasimorphism if and only if it admits a certain type of action on a poset. Our proof is based on a construction of quasimorphisms which generalizes Poincaré--Ghys' construction of the classical translation number quasimorphism. We then develop a correspondence between quasimorphisms and actions on poset

Luis F. Lafuerza, Raul Toral

We study a stochastic model of protein dynamics that explicitly includes delay in the degradation. We rigorously derive the master equation for the processes and solve it exactly. We show that the equations for the mean values obtained differ from others intuitively proposed and that oscillatory behavior is not possible in this system. We discuss the calcula

Tao Li

We construct a counterexample to the Rank versus Genus Conjecture, i.e. a closed orientable hyperbolic 3-manifold with rank of its fundamental group smaller than its Heegaard genus. Moreover, we show that the discrepancy between rank and Heegaard genus can be arbitrarily large for hyperbolic 3-manifolds. We also construct toroidal such examples containing hy

E. Müller, H. -Th. Janka, A. Wongwathanarat

Time-dependent and direction-dependent neutrino and gravitational-wave (GW) signatures are presented for a set of 3D hydrodynamic models of parametrized, neutrino-driven supernova explosions of non-rotating 15 and 20 solar mass stars. We employ an approximate treatment of neutrino transport. Due to the excision of the high-density core of the proto-neutron s

Ian Ruchlin, Richard W. Schnee

Calculating the expected number of misclassified outcomes is a standard problem of particular interest for rare-event searches. The Clopper-Pearson method allows calculation of classical confidence intervals on the amount of misclassification if data are all drawn from the same binomial probability distribution. However, data is often better described by bre

Simone Marzani, Andrea Banfi, Mrinal Dasgupta, Lee Tomlinson

We report on the computation of the angle-between-leptons distribution in Drell-Yan processes. More precisely we study the recently introduced variable phi*, which provides us with a more accurate probe of the low Q_T domain of Z boson production at hadron colliders. Our theoretical prediction is obtained by matching a next-to-next-to leading logarithmic (NN

Ella Gale, David Pearson, Stephen Kitson, Andrew Adamatzky

Flexible solution processed memristors show different behaviour dependent on the choice of electrode material. Use of gold for both electrodes leads to switchable WORM (Write Once Read Many times) resistive devices. Use of aluminium for both electrodes increases the richness of behaviour allowing both curved and triangular memristive switching resistance mem

Michael B. Schulz

The SU(2) WZW model at large level N can be interpreted semiclassically as string theory on S^3 with N units of Neveu-Schwarz H-flux. While globally geometric, the model nevertheless exhibits an interesting doubled geometry possessing features in common with nongeometric string theory compactifications, for example, nonzero Q-flux. Therefore, it can serve as

Adan J. Corcho, Mahendra Panthee

We prove the sharp global well-posedness results for the initial value problems (IVPs) associated to the modified Korteweg-de Vries (mKdV) equation and a system modeled by the coupled modified Korteweg-de Vries equations (mKdV-system). To obtain our results we use the second generation of the modified energy and almost conserved quantities, more precisely, t

J. Mosqueira, R. I. Rey, A. Wahl, F. Vidal

The magnetization vector \vec M was measured in the reversible region of the mixed state of a high quality Tl2Ba2Ca2Cu3O10 single crystal as a function of temperature and for different magnetic field amplitudes and orientations. These measurements allowed to study the \vec M components perpendicular and parallel to the CuO2 layers (Mperp and Mpara, respectiv

Raimond Snellings

The ALICE detector at the LHC recorded first Pb-Pb collisions at 2.76 TeV in November and December of 2010. We report on the measurements of anisotropic flow for charged and identified particles. From the comparison with measurements at lower energies and with model predictions we find that the system created at these collision energies is described well by

Jaime Alvarez-Muñiz, Andrés Romero-Wolf, Enrique Zas

An in-depth characterization of coherent radio Cherenkov pulses from particle showers in dense dielectric media, referred to as the Askaryan effect, is presented. The time-domain calculation developed in this article is based on a form factor to account for the lateral dimensions of the shower. It is computationally efficient and able to reproduce the result

T. M. Godden, J. H. Quilter, A. J. Ramsay, Yanwen Wu

We demonstrate coherent optical control of a single hole spin confined to an InAs/GaAs quantum dot. A superposition of hole spin states is created by fast (10-100 ps) dissociation of a spin-polarized electron-hole pair. Full control of the hole-spin is achieved by combining coherent rotations about two axes: Larmor precession of the hole-spin about an extern

Chris Barnes, Sarah Filippi, Michael P. H. Stumpf, Thomas Thorne

For nearly any challenging scientific problem evaluation of the likelihood is problematic if not impossible. Approximate Bayesian computation (ABC) allows us to employ the whole Bayesian formalism to problems where we can use simulations from a model, but cannot evaluate the likelihood directly. When summary statistics of real and simulated data are compared

Sarah Filippi, Chris Barnes, Julien Cornebise, Michael P. H. Stumpf

Approximate Bayesian computation (ABC) has gained popularity over the past few years for the analysis of complex models arising in population genetic, epidemiology and system biology. Sequential Monte Carlo (SMC) approaches have become work horses in ABC. Here we discuss how to construct the perturbation kernels that are required in ABC SMC approaches, in or

Eric A. Bergshoeff, Sjoerd de Haan, Wout Merbis, Jan Rosseel

We study a fourth-order derivative scalar field configuration in a fixed Lifshitz background. Using an auxiliary field we rewrite the equations of motion as two coupled second order equations. We specialize to the limit that the mass of the scalar field degenerates with that of the auxiliary field and show that logarithmic modes appear. Using non-relativisti

Bernd Hezel, Michael Mayle, Peter Schmelcher

We discuss a candidate solution for the controlled trapping and manipulation of two individual Rydberg atoms by means of a magnetic Ioffe-Pritchard trap that is superimposed by a constant electric field. In such a trap Rydberg atoms experience a permanent electric dipole moment that can be of the order of several hundred Debye. The interplay of electric dipo

Eric Cockayne

The structure of finite-area topological defects in graphene is described in terms of both the direct honeycomb lattice and its dual triangular lattice. Such defects are equivalent to cutting out a patch of graphene and replacing it with a different patch with the same number of dangling bonds. An important subset of these defects, bound by a closed loop of

Yaacov E. Kraus, Ady Stern

Vortices of several condensed matter systems are predicted to have zero-energy core excitations which are Majorana fermions. These exotic quasi-particles are neutral, massless, and expected to have non-Abelian statistics. Furthermore, they make the ground state of the system highly degenerate. For a large density of vortices, an Abrikosov lattice is formed,

Chris R. Laumann, Andreas W. W. Ludwig, David A. Huse, Simon Trebst

We demonstrate that a thermal metal of Majorana fermions forms in a two-dimensional system of interacting non-Abelian (Ising) anyons in the presence of moderate disorder. This bulk metallic phase arises in the $ν=5/2$ quantum Hall state when disorder pins the anyonic quasiparticles. More generally, it naturally occurs for various proposed systems supporting

Brian P. Dolan

The mass of a black hole is interpreted, in terms of thermodynamic potentials, as being the enthalpy, with the pressure given by the cosmological constant. The volume is then defined as being the Legendre transform of the pressure and the resulting relation between volume and pressure is explored in the case of positive pressure. A virial expansion is develo

Zakria Hussain, John Shawe-Taylor, Mario Marchand

In this paper, we correct an upper bound, presented in~\cite{hs-11}, on the generalisation error of classifiers learned through multiple kernel learning. The bound in~\cite{hs-11} uses Rademacher complexity and has an\emph{additive} dependence on the logarithm of the number of kernels and the margin achieved by the classifier. However, there are some errors

Menelaos I. Karavelas, Eleni Tzanaki

We derive tight expressions for the maximum number of $k$-faces, $0\le{}k\le{}d-1$, of the Minkowski sum, $P_1\oplus{}P_2$, of two $d$-dimensional convex polytopes $P_1$ and $P_2$, as a function of the number of vertices of the polytopes. For even dimensions $d\ge{}2$, the maximum values are attained when $P_1$ and $P_2$ are cyclic $d$-polytopes with disjoin

I. A. Gospodarev, V. I. Grishaev, O. V. Kotlyar, K. V. Kravchenko

Phonon spectra of solid substitutional solutions with finite concentrations of impurities were analyzed on the microscopic level. The local phonon densities of impurity atoms were calculated, in particular the formation of quasilocal vibrations and their evolution with increasing of the concentration of impurities were investigated. Modification of the local

Mauricio A. Alvarez, Lorenzo Rosasco, Neil D. Lawrence

Kernel methods are among the most popular techniques in machine learning. From a frequentist/discriminative perspective they play a central role in regularization theory as they provide a natural choice for the hypotheses space and the regularization functional through the notion of reproducing kernel Hilbert spaces. From a Bayesian/generative perspective th

Michal Adamaszek

We use two cofibre sequences to identify some combinatorial situations when the independence complex of a graph splits into a wedge sum of smaller independence complexes. Our main application is to give a recursive relation for the homotopy types of the independence complexes of powers of cycles, which answers an open question of D. Kozlov.

Daniel Boyanovsky

For neutrino oscillations to take place the entangled quantum state of a neutrino and a charged lepton produced via charged current interactions must be disentangled. Implementing a non-perturbative Wigner-Weisskopf method we obtain the correct \emph{entangled} quantum state of neutrinos and charged leptons from the (two-body) decay of a parent particle. The

S. N. Stelmastchuk

The subject of this work is to study martingales in a reductive homogeneous space with respect to a symmetric connection. Our basic idea is to view homogenous spaces as principal fiber bundles and, thus, to study martingales on homogeneous space with aid of horizontal martingales on Lie group. Furthermore, using the stochastic logarithm we give a characteriz

Thomas Hackman, Maarit J. Mantere, Marjaana Lindborg, Ilya Ilyin

Aims. We study the spot activity of II Peg during the years 2004-2010 to determine long- and short-term changes in the magnetic activity. In a previous study, we detected a persistent active longitude, as well as major changes in the spot configuration occurring on a timescale of shorter than a year. The main objective of this study is to determine whether t

Valentin Féray, Victor Reiner

We compare a traditional and non-traditional view on the subject of P-partitions, leading to formulas counting linear extensions of certain posets.

Debajyoti Choudhury, Debashis Ghoshal, Anjan Ananda Sen

The introduction of a delay in the Friedmann equation of cosmological evolution is shown to result in the very early universe undergoing the necessary accelerated expansion in the usual radiation (or matter) dominated phase. Occurring even without a violation of the strong energy condition, this expansion slows down naturally to go over to the decelerated ph

Björn Herrmann, Michael Klasen, Quentin Le Boulc'h

We discuss the possibility of new sources of flavour violation in the squark sector of supersymmetric models in the context of the dark matter relic density. We show that the corresponding non-minimal flavour violation terms in the squark mass matrices can have an important impact on the thermally averaged (co)annihilation cross section of the neutralino, an

V. Vacca, F. Govoni, M. Murgia, G. Giovannini

The aim of this work is to investigate the possible presence of extended diffuse synchrotron radio emission associated with the intracluster medium of the complex galaxy cluster A1689. The radio continuum emission of A1689 has been investigated by analyzing archival observations at 1.2 and 1.4 GHz obtained with the Very Large Array in different configuration

Marco F. Duarte, Yonina C. Eldar

Compressed sensing (CS) is an emerging field that has attracted considerable research interest over the past few years. Previous review articles in CS limit their scope to standard discrete-to-discrete measurement architectures using matrices of randomized nature and signal models based on standard sparsity. In recent years, CS has worked its way into severa

Ben Xu, M. V. Milošević, Shi-Hsin Lin, F. M. Peeters

The ground state with vorticity larger than one in mesoscopic superconductors in applied magnetic field may manifest as a `giant'-vortex, where all vortices coalesce into a single singularity of the order parameter. Such a multi-quanta vortex may split into individual vortices (and vice versa) as a function of e.g. applied current, magnetic field or temp

Yochay Eshel, Seung J. Lee, Gilad Perez, Yotam Soreq

We study radion phenomenology in the context of flavor shining in warped extra dimension models. In this unique setup, originally proposed by Rattazzi and Zaffaroni, solutions to the gauge hierarchy problem and the new physics flavor problem are unified. A special role is played by the vacuum energy on the branes, that naturally allows for flavon stabilizati

Leonardo Ermann, Alexei D. Chepelianskii, Dima L. Shepelyansky

We study the statistical properties of various directed networks using ranking of their nodes based on the dominant vectors of the Google matrix known as PageRank and CheiRank. On average PageRank orders nodes proportionally to a number of ingoing links, while CheiRank orders nodes proportionally to a number of outgoing links. In this way the ranking of node

Hyo-Sil Kim, Otfried Cheong

We study the motion-planning problem for a car-like robot whose turning radius is bounded from below by one and which is allowed to move in the forward direction only (Dubins car). For two robot configurations $σ, σ'$, let $\ell(σ, σ')$ be the shortest bounded-curvature path from $σ$ to $σ'$. For $d \geq 0$, let $\ell(d)$ be the supremum of $\ell

C. Schill

The investigation of transverse spin and transverse momentum effects in the nucleon is one of the key physics programs of the COMPASS experiment at CERN. COMPASS investigates these effects scattering 160 GeV/c muons off a fixed NH3 or 6LiD target. The azimuthal asymmetries which appear in the cross-section of semi-inclusive deep-inelastic scattering on an un

Francesco Caravenna, Frank den Hollander, Nicolas Pétrélis

These lecture notes are a guided tour through the fascinating world of polymer chains interacting with themselves and/or with their environment. The focus is on the mathematical description of a number of physical and chemical phenomena, with particular emphasis on phase transitions and space-time scaling. The topics covered, though only a selection, are typ

Naokazu Shibata, Chisa Hotta

We investigate the boundary effect of the density matrix renormalization group calculation (DMRG), which is an artifactual induction of symmetry-breaking pseudo-long-range order and takes place when the long-range quantum fluctuation cannot be properly included in the variational wave function due to numerical limitation. The open boundary condition often us

Thomas W. Kephart, Philipp Leser, Heinrich Päs

We propose a third idea for the explanation of the leptonic flavor structure in addition to the prominent approaches based on flavor symmetry and anarchy. Typical flavor patterns can be modeled by using mass spectra obtained from the discrete lengths spectrum of tight knots and links. We assume that a string theory model exists in which this idea can be inco

Jeremy Andrea, Benjamin Fuks, Fabio Maltoni

We explore scenarios where top quarks may be produced singly in association with missing energy, a very distinctive signature, which in analogy with monojets, we dub monotops. We find that monotops can be produced in a variety of modes, typically characterized by baryon number violating or flavor changing neutral interactions. We build a simplified model tha

Guus Regts

We characterize the rank of edge connection matrices of partition functions of real vertex models, as the dimension of the homogeneous components of the algebra of $G$-invariant tensors. Here $G$ is the sub- group of the real orthogonal group that stabilizes the vertex model. This answers a question of Balázs Szegedy from 2007.

J. A. Bergstra, C. A. Middelburg

We study several aspects of the behaviours produced by instruction sequences under execution in the setting of the algebraic theory of processes known as ACP. We use ACP to describe the behaviours produced by instruction sequences under execution and to describe two protocols implementing these behaviours in the case where the processing of instructions take

Dominique Lambert, Bertrand Hespel

Our aim is to give some insights about how to approach the formal description of situations where one has to conciliate several contradictory statements, rules, laws or ideas. We show that such a conciliation structure can be naturally defined on a topological space endowed with the set of its closed sets and that this specific structure is a kind of "du

Issa Karambal, Simon J. A Malham

We explore the relationship between the Evans function, transmission coefficient and Fredholm determinant for systems of first order linear differential operators on the real line. The applications we have in mind include linear stability problems associated with travelling wave solutions to nonlinear partial differential equations, for example reaction-diff

F. Palestini, A. Perali, P. Pieri, G. C. Strinati

The dispersions, weights, and widths of the peaks of the single-particle spectral function in the presence of pair correlations, for a Fermi gas with either attractive or repulsive short-range inter-particle interaction, are determined in the normal phase over a wide range of wave vectors, with a twofold purpose. The first one is to determine how these dispe

Gábor Ivanyos, Lajos Rónyai, Josef Schicho

Let K be an algebraic number field of degree d and discriminant D over Q. Let A be an associative algebra over K given by structure constants such that A is isomorphic to the algebra M_n(K) of n by n matrices over K for some positive integer n. Suppose that d, n and D are bounded. Then an isomorphism of A with M_n(K) can be constructed by a polynomial time f

Bernhard Baumgartner

The absolute value of matrices is used in order to give inequalities for the trace of products. An application gives a very short proof of the tracial matrix Hoelder inequality

Jihong Qin, Yu Lan, Shiping Feng

Within the two-leg $t$-J ladder, the spin dynamics of the pressure-induced two-leg ladder cuprate superconductor Sr$_{14-x}$Ca$_{x}$Cu$_{24}$O$_{41}$ is studied based on the kinetic energy driven superconducting mechanism. It is shown that in the pressure-induced superconducting state, the incommensurate spin correlation appears in the underpressure regime,

Antoine Touzé

In this article, we apply some ideas developped by M. Chałupnik to the framework of strict polynomial bifunctors. This allows us to get a new proof of the existence of the `universal classes' originally constructed by the author.

Joseph Manjavidze

It is noted that quantum theory includes the correspondence principle which is independent of the value of quantum corrections. Some consequences of this generalized correspondence principle are considered. For example, it is discussed how the symmetry constraints can be taken into account.

Santiago F. Caballero-Benitez, Rosario Paredes

We study stationary and dynamical properties of the many-body Landau-Zener dynamics of a Bose quantum fluid confined in two coupled one-dimensional chains, using a many-body generalization recently reported [Y.-A. Chen et al.], within the decoupling approximation and the one-level band scheme. The energy spectrum evidences the structure of the avoided level

Oleg S. Ugolnikov, Igor A. Maslov, Stanislav A. Korotkiy

The paper contains the result description of the photometric observations of the Moon surface during the total lunar eclipse of June, 15, 2011 conducted in southern Russia and Ukraine in three narrow spectral bands with effective wavelengths equal to 503, 677, and 867 nm. The photometric maps of umbra are built, the radial dependencies of relative brightness

Florian Hebenstreit, Reinhard Alkofer, Holger Gies

Non-perturbative electron-positron pair creation (Schwinger effect) is studied based on the equal-time Wigner formalism in 1+1 dimensions. An ab initio calculation of the Schwinger effect in the presence of a simple space- and time-dependent electric field pulse is performed for the first time, allowing for the calculation of the time evolution of observable

Jianquan Liu, Meixia Tao, Youyun Xu

Partial decoding has the potential to achieve a larger capacity region than full decoding in two-way relay (TWR) channels. Existing partial decoding realizations are however designed for Gaussian channels and with a static physical layer network coding (PLNC). In this paper, we propose a new solution for joint network coding and channel decoding at the relay