Skip to main content
Internet Archive's 25th Anniversary Logo

4,278
UPLOADS


More right-solid

Show sorted alphabetically

More right-solid

Show sorted alphabetically

More right-solid

More right-solid
SHOW DETAILS
eye
Title
Date Archived
Creator
Arxiv.org
by Stephen Serjeant
texts

eye 62

favorite 0

comment 0

Bright submm-selected galaxies have been found to be a rich source of strong gravitational lenses. However, strong gravitational lensing of extended sources leads inevitably to differential magnification. In this paper I quantify the effect of differential magnification on simulated far-infrared and submm surveys of strong gravitational lenses, using a foreground population of Navarro-Frenk-White plus de Vaucouleurs' density profiles, with a model source resembling the Cosmic Eyelash and QSO...
Source: http://arxiv.org/abs/1203.2647v2
Arxiv.org
by Franco Buccella; Domenico Falcone; Chee Sheng Fong; Enrico Nardi; Giulia Ricciardi
texts

eye 83

favorite 0

comment 0

We consider the see-saw mechanism within a non-supersymmetric SO(10) model. By assuming the SO(10) quark-lepton symmetry, and after imposing suitable conditions that ensure that the right-handed (RH) neutrino masses are at most mildly hierarchical (compact RH spectrum) we obtain a surprisingly predictive scenario. The absolute neutrino mass scale, the Dirac and the two Majorana phases of the neutrino mixing matrix remain determined in terms of the set of already measured low energy observables,...
Source: http://arxiv.org/abs/1203.0829v2
Arxiv.org
texts

eye 59

favorite 0

comment 0

We propose a modified procedure for extracting the numerical value for the strong coupling constant $\alpha_s$ from the $\tau$ lepton hadronic decay rate into non-strange particles in the vector channel. We employ the concept of the quark-hadron duality specifically, introducing a boundary energy squared $s_{\rm p}>0$, the onset of the perturbative QCD continuum in Minkowski space \cite{BLR,Rafa,PPR}. To approximate the hadronic spectral function in the region $s>s_{\rm p}$, we use...
Source: http://arxiv.org/abs/1005.2674v3
Arxiv.org
texts

eye 71

favorite 0

comment 0

Random coding, along with various standard techniques such as coded time-sharing, rate-splitting, superposition coding, and binning, are traditionally used in obtaining achievable rate regions for multi-terminal networks. The error analysis of such an achievable scheme relies heavily on the properties of strongly joint typical sequences and on bounds of the cardinality of typical sets. In this work, we obtain an achievable rate region for a general (i.e. an arbitrary set of messages shared...
Source: http://arxiv.org/abs/1107.4705v2
Arxiv.org
by Per Berglund; Jishnu Bhattacharyya; David Mattingly
texts

eye 32

favorite 0

comment 0

We study electromagnetically charged dilatonic black brane solutions in arbitrary dimensions with flat transverse spaces, that are asymptotically AdS. This class of solutions includes spacetimes which possess a bulk region where the metric is approximately invariant under Lifshitz scalings. Given fixed asymptotic boundary conditions, we analyze how the behavior of the bulk up to the horizon varies with the charges and derive the extremality conditions for these spacetimes.
Source: http://arxiv.org/abs/1107.3096v2
Arxiv.org
texts

eye 52

favorite 0

comment 0

A nonlinear electromagnetic scattering problem is studied in the presence of bound states in the radiation continuum. It is shown that the solution is not analytic in the nonlinear susceptibility and the conventional perturbation theory fails. A non-perturbative approach is proposed and applied to the system of two parallel periodic arrays of dielectric cylinders with a second order nonlinear susceptibility. This scattering system is known to have bound states in the radiation continuum. In...
Source: http://arxiv.org/abs/1107.0468v2
Arxiv.org
by R. Parthasarathy
texts

eye 95

favorite 0

comment 0

The apparent violation of causality in the brane Universe can be avoided by taking the bulk spacetime modelled by a 5-dimensional Kaluza theory with factorizable ansatz for the 5-dimensional metric whose components do not depend on the fifth coordinate and with $G_{55}$ not a constant. The geodesic in the bulk does not correspond to a free particle. The Kaluza scalar makes it non-inertial. The implication on the neutrino experiment is that there is no superluminal propagation even after...
Source: http://arxiv.org/abs/1203.6192v1
Arxiv.org
by Friedrich Götze; Andrei Yu. Zaitsev
texts

eye 66

favorite 0

comment 0

The aim of this paper is to investigate, which infinite dimensional consequences follow from the main results of recently published paper of the authors (2009) (see Theorems 2 and 3). We show that the finite dimensional Theorem 3 implies meaningful estimates for the rate of strong Gaussian approximation of sums of i.i.d. Hilbert space valued random vectors $\xi_j$ with finite moments $E |\xi_j|^\gamma$, $\gamma>2$. We show that the rate of approximation depends substantially on the rate of...
Source: http://arxiv.org/abs/1203.5695v1
Arxiv.org
by Gil R. Cavalcanti
texts

eye 52

favorite 0

comment 0

We use the procedure of reduction of Courant algebroids to reduce strong KT, hyper KT and generalized Kaehler structures on Courant algebroids. This allows us to recover results from the literature as well as explain from a different angle some of the features observed there in. As an example, we prove that the moduli space of instantons of a bundle over a SKT/HKT/generalized K\"ahler manifold is endowed with the same type of structure as the original manifold.
Source: http://arxiv.org/abs/1203.0497v1
Arxiv.org
by Subhamoy Ghatak; Atindra Nath Pal; Arindam Ghosh
texts

eye 258

favorite 0

comment 0

We present low temperature electrical transport experiments in five field effect transistor devices consisting of monolayer, bilayer and trilayer MoS2 films, mechanically exfoliated onto Si/SiO2 substrate. Our experiments reveal that the electronic states in all films are localized well up to the room temperature over the experimentally accessible range of gate voltage. This manifests in two dimensional (2D) variable range hopping (VRH) at high temperatures, while below \sim 30 K the...
Source: http://arxiv.org/abs/1203.5656v1
Arxiv.org
by B. Parise; F. Du; F. -C. Liu; A. Belloche; H. Wiesemeyer; R. Güsten; K. M. Menten; H. W. Hübers; B. Klein
texts

eye 49

favorite 0

comment 0

Although water is an essential and widespread molecule in star-forming regions, its chemical formation pathways are still not very well constrained. Observing the level of deuterium fractionation of OH, a radical involved in the water chemical network, is a promising way to infer its chemical origin. We aim at understanding the formation mechanisms of water by investigating the origin of its deuterium fractionation. This can be achieved by observing the abundance of OD towards the low-mass...
Source: http://arxiv.org/abs/1203.2825v1
Arxiv.org
by Andreas Andresen; Peter Imkeller; Nicolas Perkowski
texts

eye 69

favorite 0

comment 0

Ciesielski's isomorphism between the space of alpha-H\"older continuous functions and the space of bounded sequences is used to give an alternative proof of the large deviation principle for Wiener processes with values in Hilbert space.
Source: http://arxiv.org/abs/1203.4596v1
Arxiv.org
by S. H. P. Alencar; J. Bouvier; F. M. Walter; C. Dougados; J. -F. Donati; R. Kurosawa; M. Romanova; X. Bonfils; G. H. R. A. Lima; S. Massaro; M. Ibrahimov; E. Poretti
texts

eye 59

favorite 0

comment 0

We analyze the photometric and spectroscopic variability of the classical T Tauri star V2129 Oph over several rotational cycles to test the dynamical predictions of magnetospheric accretion models. The photometric variability and the radial velocity variations in the photospheric lines can be explained by rotational modulation due to cold spots, while the radial velocity variations of the He I (5876 \AA) line and the veiling variability are due to hot spot rotational modulation. The hot and...
Source: http://arxiv.org/abs/1203.6331v1
Arxiv.org
by Yi Huang
texts

eye 64

favorite 0

comment 0

We prove a McShane-type identity - a series, expressed in terms of geodesic lengths, that sums to 2\pi for any closed hyperbolic surface with one distinguished point. To do so, we prove a generalized Birman-Series theorem showing that the set of complete geodesics on a hyperbolic surface with large cone angles is sparse.
Source: http://arxiv.org/abs/1203.3860v4
Arxiv.org
by C. S. Lopez-Monsalvo; F. Nettel; A. Sanchez
texts

eye 126

favorite 0

comment 0

We comment on the conclusions found by Larra\~naga and Mojica regarding the consistency of the Geoemtrothermodynamics programme to describe the critical behaviour of a Gibbons-Maeda-Garfinkle-Horowitz-Strominger charged black hole. We argue that making the appropriate choice of metric for the thermodynamic phase space and, most importantly, considering the homogeneity of the thermodynamic potential we obtain consistent results for such a black hole.
Source: http://arxiv.org/abs/1203.6444v1
Arxiv.org
texts

eye 35

favorite 0

comment 0

Fermion production in an external Coulomb field on de Sitter expanding universe is studied. The amplitude and probability of pair production in an external Coulomb field are computed and the cases of large/small values of the expansion factor comparatively with the particle mass are studied. We obtain from our calculations that the modulus of the momentum is no longer a conserved quantity. We find that in the de Sitter space there are probabilities for production processes where the helicity is...
Source: http://arxiv.org/abs/1203.0151v1
Arxiv.org
texts

eye 39

favorite 0

comment 0

We investigate femtoscopic $\pi \pi$ correlations using the UrQMD approach combined with a correlation afterburner. The dependence of $\pi \pi$ correlations on the charged particle multiplicity and formation time in p+p collisions at $\sqrt{s_{NN}}$= 7 TeV is explored and compared to present ALICE data. The data allows to constrain the formation time in the string fragmentation to $\tau_f \leq 0.8$ fm/c.
Source: http://arxiv.org/abs/1203.4421v1
Arxiv.org
by Weiyu Xu; Alex Dimakis; Babak Hassibi
texts

eye 49

favorite 0

comment 0

In this paper, we study the mixing time of Markov Chain Monte Carlo (MCMC) for integer least-square (LS) optimization problems. It is found that the mixing time of MCMC for integer LS problems depends on the structure of the underlying lattice. More specifically, the mixing time of MCMC is closely related to whether there is a local minimum in the lattice structure. For some lattices, the mixing time of the Markov chain is independent of the signal-to-noise ($SNR$) ratio and grows polynomially...
Source: http://arxiv.org/abs/1203.2213v1
Arxiv.org
texts

eye 39

favorite 0

comment 0

The secondary-to-primary B/C ratio is widely used to study the cosmic ray (CR) propagation processes in the Galaxy. It is usually assumed that secondary nuclei such as Li-Be-B are entirely generated by collisions of heavier CR nuclei with the interstellar medium (ISM). We study the CR propagation under a scenario where secondary nuclei can also be produced or accelerated from galactic sources. We consider the processes of hadronic interactions inside supernova remnants (SNRs) and...
Source: http://arxiv.org/abs/1203.6094v2
Internet Archive Presents
by Internet Archive
movies

eye 636

favorite 0

comment 0

12 Hours Dark: Internet Archive vs. Censorship From hackersandfounders.com : Silicon Valley PIPA/SOPA Protest Wednesday, January 18, 2012, 12:00 PM Civic Center Plaza Fulton and Larkin, San Francisco, CA (map) Global PIPA / SOPA protests are a go. Websites all over the globe are going Dark to protest radical copyright legislation. Tech meetup groups around the country are joining forces to rally against PIPA. Join us for a rally in San Francisco on Wednesday starting at 12:00pm Speaking:...
Topic: SOPA, PIPA, Internet Censorship, Internet Archive, Brewster Kahle
Arxiv.org
by Richard J. Szabo; Miguel Tierz
texts

eye 49

favorite 0

comment 0

We show that the partition functions which enumerate Donaldson-Thomas invariants of local toric Calabi-Yau threefolds without compact divisors can be expressed in terms of specializations of the Schur measure. We also discuss the relevance of the Hall-Littlewood and Jack measures in the context of BPS state counting and study the partition functions at arbitrary points of the Kaehler moduli space. This rewriting in terms of symmetric functions leads to a unitary one-matrix model representation...
Source: http://arxiv.org/abs/1005.5643v3
Arxiv.org
by Josep Diaz; Alberto Marchetti-Spaccamela; Dieter Mitsche; Paolo Santi; Julinda Stefa
texts

eye 90

favorite 0

comment 0

Several social-aware forwarding strategies have been recently introduced in opportunistic networks, and proved effective in considerably in- creasing routing performance through extensive simulation studies based on real-world data. However, this performance improvement comes at the expense of storing a considerable amount of state information (e.g, history of past encounters) at the nodes. Hence, whether the benefits on routing performance comes directly from the social-aware forwarding...
Source: http://arxiv.org/abs/1007.5240v2
Arxiv.org
by Kenji Iohara; Olivier Mathieu
texts

eye 42

favorite 0

comment 0

Let $\Lambda$ be a lattice of rank $n$. A Lie algebra on the lattice $\Lambda$ is a Lie algebra ${\cal L}=\oplus_{\lambda\in\Lambda}\,{\cal L}_{\lambda}$ such that $\dim\,{\cal L}_\lambda=1$ for all $\lambda$. In this article, we classify all simple graded Lie algebras on a lattice.
Source: http://arxiv.org/abs/1107.2082v2
Arxiv.org
by G. Agakishiev; for the STAR Collaboration
texts

eye 94

favorite 0

comment 0

Vector mesons may be photoproduced in relativistic heavy-ion collisions when a virtual photon emitted by one nucleus scatters from the other nucleus, emerging as a vector meson. The STAR Collaboration has previously presented measurements of coherent $\rho^0$ photoproduction at center of mass energies of 130 GeV and 200 GeV in AuAu collisions. Here, we present a measurement of the cross section at 62.4 GeV; we find that the cross section for coherent $\rho^0$ photoproduction with nuclear...
Source: http://arxiv.org/abs/1107.4630v2
Arxiv.org
texts

eye 44

favorite 0

comment 0

This paper shows that a finitely presented monoid with linear Dehn function need not have a regular cross-section, strengthening the previously-known result that such a monoid need not be presented by a finite complete string rewriting system, and contrasting the fact that finitely presented groups with linear Dehn function always have regular cross-sections.
Source: http://arxiv.org/abs/1203.0473v1
Arxiv.org
by Lidia Angeleri Hügel; David Pospisil; Jan Stovicek; Jan Trlifaj
texts

eye 52

favorite 0

comment 0

We classify all tilting and cotilting classes over commutative noetherian rings in terms of descending sequences of specialization closed subsets of the Zariski spectrum. Consequently, all resolving subcategories of finitely generated modules of bounded projective dimension are classified. We also relate our results to Hochster's conjecture on the existence of finitely generated maximal Cohen-Macaulay modules.
Source: http://arxiv.org/abs/1203.0907v3
This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W...
Source: http://arxiv.org/abs/1203.2165v2
Arxiv.org
by Oscar F. Hernandez; Robert H. Brandenberger
texts

eye 53

favorite 0

comment 0

The analysis of the 21 cm signature of cosmic string wakes is extended in several ways. First we consider the constraints on $G\mu$ from the absorption signal of shock heated wakes laid down much later than matter radiation equality. Secondly we analyze the signal of diffuse wake, that is those wakes in which there is a baryon overdensity but which have not shock heated. Finally we compare the size of these signals compared to the expected thermal noise per pixel which dominates over the...
Source: http://arxiv.org/abs/1203.2307v3
Arxiv.org
by F. Arias de Saavedra; F. Mazzanti; J. Boronat; A. Polls
texts

eye 119

favorite 0

comment 0

We use microscopic many-body theory to analyze the problem of itinerant ferromagnetism in a repulsive atomic Fermi gas of Hard Spheres. Using simple arguments, we show that the available theoretical predictions for the onset of the ferromagnetic transition predict a transition point at a density ($k_F a \sim 1$) that is too large to be compatible with the universal low-density expansion of the energy. We present new variational calculations for the hard-sphere Fermi gas, in the framework of...
Source: http://arxiv.org/abs/1203.2521v1
Arxiv.org
texts

eye 38

favorite 0

comment 0

We investigate the large time behavior of an axisymmetric model for the 3D Euler equations. In \cite{HL09}, Hou and Lei proposed a 3D model for the axisymmetric incompressible Euler and Navier-Stokes equations with swirl. This model shares many properties of the 3D incompressible Euler and Navier-Stokes equations. The main difference between the 3D model of Hou and Lei and the reformulated 3D Euler and Navier-Stokes equations is that the convection term is neglected in the 3D model. In...
Source: http://arxiv.org/abs/1203.2980v1
Arxiv.org
by Hiroyuki Hirashita; Takaya Nozawa
texts

eye 131

favorite 0

comment 0

We examine a synthetic way of constructing the grain size distribution in the interstellar medium (ISM). First we formulate a synthetic grain size distribution composed of three grain size distributions processed with the following mechanisms that govern the grain size distribution in the Milky Way: (i) grain growth by accretion and coagulation in dense clouds, (ii) supernova shock destruction by sputtering in diffuse ISM, and (iii) shattering driven by turbulence in diffuse ISM. Then, we...
Source: http://arxiv.org/abs/1203.4298v1
Arxiv.org
by Jost Neigenfind; Sergio Grimbs; Zoran Nikoloski
texts

eye 42

favorite 0

comment 0

Robustness of biochemical systems has become one of the central questions in systems biology although it is notoriously difficult to formally capture its multifaceted nature. Maintenance of normal system function depends not only on the stoichiometry of the underlying interrelated components, but also on a multitude of kinetic parameters. Invariant flux ratios, obtained within flux coupling analysis, as well as invariant complex ratios, derived within chemical reaction network theory, can...
Source: http://arxiv.org/abs/1203.5932v1
Arxiv.org
by Bhubanjyoti Bhattacharya; Jonathan L. Rosner
texts

eye 42

favorite 0

comment 0

The processes $D^0\to K^0 K^-\pi^+$ and $D^0\to\ok K^+\pi^-$ involve intermediate vector resonances whose amplitudes and phases are related to each other via flavor-SU(3) symmetry. Dalitz plots for these two processes can shed light on the usefulness of this symmetry in studying charm decays. Until this year the only available data on this process came from a conference report in 2002 by the BaBar Collaboration, but now an independent data sample of higher statistics has become available from...
Source: http://arxiv.org/abs/1203.6014v3
Arxiv.org
by Hongmei Wang; Yajiang Hao; Yunbo Zhang
texts

eye 140

favorite 0

comment 0

We present a density-functional theory for the one dimensional harmonically trapped Bose-Fermi mixture with repulsive contact interactions. The ground state density distribution of each component is obtained by solving the Kohn-Sham equations numerically based on the Local Density Approximation and the exact solution for the homogeneous system given by Bethe ansatz method. It is shown that for strong enough interaction, a considerable amount of fermions are repelled out of the central region of...
Source: http://arxiv.org/abs/1203.6211v1
Arxiv.org
by H. F. Chau; C. -K. Li; Y. -T. Poon; N. -S. Sze
texts

eye 47

favorite 0

comment 0

Recently, Chau [Quant. Inform. & Comp. 11, 721 (2011)] showed that one can define certain metrics and pseudo-metrics on U(n), the group of all $n\times n$ unitary matrices, based on the arguments of the eigenvalues of the unitary matrices. More importantly, these metrics and pseudo-metrics have quantum information theoretical meanings. So it is instructive to study this kind of metrics and pseudo-metrics on U(n). Here we show that any symmetric norm on ${\mathbb R}^n$ induces a metric on...
Source: http://arxiv.org/abs/1107.1047v2
Arxiv.org
texts

eye 91

favorite 0

comment 0

In this paper we obtain new properties of a signal generated by the Riemann zeta-function on the critical line. At the same time we obtain an asymptotic formula for a new class of transcendental integrals connected with the Riemann zeta-function.
Source: http://arxiv.org/abs/1203.0159v1
Arxiv.org
by Alexandre Lung-Yut-Fong; Céline Lévy-Leduc; Olivier Cappé
texts

eye 46

favorite 0

comment 0

Detecting and locating changes in highly multivariate data is a major concern in several current statistical applications. In this context, the first contribution of the paper is a novel non-parametric two-sample homogeneity test for multivariate data based on the well-known Wilcoxon rank statistic. The proposed two-sample homogeneity test statistic can be extended to deal with ordinal or censored data as well as to test for the homogeneity of more than two samples. The second contribution of...
Source: http://arxiv.org/abs/1107.1971v3
Arxiv.org
by H. Bruntt; S. Basu; B. Smalley; W. J. Chaplin; G. A. Verner; T. R. Bedding; C. Catala; J. -C. Gazzano; J. Molenda-Zakowicz; A. O. Thygesen; K. Uytterhoeven; S. Hekker; D. Huber; C. Karoff; S. Mathur; B. Mosser; T. Appourchaux; T. L. Campante; Y. Elsworth; R. A. Garcia; R. Handberg; T. S. Metcalfe; P. -O. Quirion; C. Regulo; I. W. Roxburgh; D. Stello; J. Christensen-Dalsgaard; S. D. Kawaler; H. Kjeldsen; R. L. Morris; E. V. Quintana; D. T. Sanderfer
texts

eye 160

favorite 0

comment 0

We present a detailed spectroscopic study of 93 solar-type stars that are targets of the NASA/Kepler mission and provide detailed chemical composition of each target. We find that the overall metallicity is well-represented by Fe lines. Relative abundances of light elements (CNO) and alpha-elements are generally higher for low-metallicity stars. Our spectroscopic analysis benefits from the accurately measured surface gravity from the asteroseismic analysis of the Kepler light curves. The log g...
Source: http://arxiv.org/abs/1203.0611v1
Arxiv.org
by Mugurel Ţolea; Bogdan Ostahie; Marian Niţă; Felicia Ţolea; Alexandru Aldea
texts

eye 43

favorite 0

comment 0

The phase of the electronic wave function is not directly measurable but, quite remarkably, it becomes accessible in pairs of isospectral shapes, as recently proposed in the experiment of Christopher R. Moon {\it et al.}, Science {\bf 319}, 782 (2008). The method is based on a special property, called transplantation, which relates the eigenfunctions of the isospectral pairs, and allows to extract the phase distributions, if the amplitude distributions are known. We numerically simulate such a...
Source: http://arxiv.org/abs/1203.0717v1
Arxiv.org
by Sebastian Casalaina-Martin; Radu Laza
texts

eye 43

favorite 0

comment 0

A key tool in the study of algebraic surfaces and their moduli is Brieskorn's simultaneous resolution for families of algebraic surfaces with simple (du Val or ADE) singularities. In this paper we show that a similar statement holds for families of curves with at worst simple (ADE) singularities. For a family $\mathscr X\to B$ of ADE curves, we give an explicit and natural resolution of the rational map $B\to \bar M_g$. Moreover, we discuss a lifting of this map to the moduli stack $ \bar...
Source: http://arxiv.org/abs/1007.0265v2
Arxiv.org
by M. F. Cornelio; O. Jiménez Farías; F. F. Fanchini; I. Frerot; G. H. Aguilar; M. O. Hor-Meyll; M. C. de Oliveira; S. P. Walborn; A. O. Caldeira; P. H. Souto Ribeiro
texts

eye 75

favorite 0

comment 0

We use the classical correlation between a quantum system being measured and its measurement apparatus to analyze the amount of information being retrieved in a quantum measurement process. Accounting for decoherence of the apparatus, we show that these correlations may have a sudden transition from a decay regime to a constant level. This transition characterizes a non-asymptotic emergence of the pointer basis, while the system-apparatus can still be quantum correlated. We provide a...
Source: http://arxiv.org/abs/1203.5068v2
Arxiv.org
by A. Fête; S. Gariglio; A. D. Caviglia; J. -M. Triscone; M. Gabay
texts

eye 67

favorite 0

comment 0

We report measurements of the normal state in-plane magnetoconductance in gated LaAlO$_3$-SrTiO$_3$ samples. As the orientation of the magnetic field changes within the plane of the interface, the signal displays periodic oscillations with respect to the angle between the field and the direction of the current. We show that in the underdoped to optimally doped range, a Fermi surface reconstruction takes place due to the Rashba spin-orbit term and that the oscillations are due to a magnetic...
Source: http://arxiv.org/abs/1203.5239v2
Arxiv.org
by Michele Cicoli; Anshuman Maharana; F. Quevedo; C. P. Burgess
texts

eye 38

favorite 0

comment 0

We consider a novel scenario for modulus stabilisation in IIB string compactifications in which the Kahler moduli are stabilised by a general set-up with two kinds of non-perturbative effects: (i) standard Kahler moduli-dependent non-perturbative effects from gaugino condensation on D7-branes or E3-instantons wrapping four-cycles in the geometric regime; (ii) dilaton-dependent non-perturbative effects from gaugino condensation on space-time filling D3-branes or E(-1)-instantons at...
Source: http://arxiv.org/abs/1203.1750v2
Arxiv.org
texts

eye 54

favorite 0

comment 0

In this paper, we prove that the inverse problems for 2D elasticity and for the thin plate with boundary data (finite or full measurements) are equivalent. Having proved this equivalence, we can solve inverse problems for the plate equation with boundary data by solving the corresponding inverse problems for 2D elasticity, and vice versa. For example, we can derive bounds on the volume fraction of the two-phase thin plate from the knowledge of one pair of boundary measurements using the known...
Source: http://arxiv.org/abs/1203.3833v1
Arxiv.org
texts

eye 63

favorite 0

comment 0

In this note we review the construction of topologically gauged M2 branes with 6 supersymmetries and discuss some of its properties. This is done using the 3-algebra formulation thereby covering all possible gauge groups. We will elaborate upon 1) the fundamental identity and its solutions noting, provided these gauged theories describe stacks of branes, the case of a single brane, 2) the chiral point solution to the field equations (occuring even for a single brane) that breaks the...
Source: http://arxiv.org/abs/1203.5090v1
Arxiv.org
by K. Arisaka; P. Beltrame; C. W. Lam; P. F. Smith; C. Ghag; D. B. Cline; K. Lung; Y. Meng; E. Pantic; P. R. Scovell; A. Teymourian; H. Wang
texts

eye 187

favorite 0

comment 0

We study a three stage dark matter and neutrino observatory based on multi-ton two-phase liquid Xe and Ar detectors with sufficiently low backgrounds to be sensitive to WIMP dark matter interaction cross sections down to 10E-47 cm^2, and to provide both identification and two independent measurements of the WIMP mass through the use of the two target elements in a 5:1 mass ratio, giving an expected similarity of event numbers. The same detection systems will also allow measurement of the pp...
Source: http://arxiv.org/abs/1107.1295v3
Arxiv.org
by Ralf Aurich; Sven Lustig
texts

eye 47

favorite 0

comment 0

The cosmic microwave background (CMB) anisotropy possesses the remarkable property that its power is strongly suppressed on large angular scales. This observational fact can naturally be explained by cosmological models with a non-trivial topology. The paper focuses on lens spaces L(p,q) which are realised by a tessellation of the spherical 3-space S^3 by cyclic deck groups of order p = 60^\circ suppressed by a factor of two compared to the simply connected S^3 space. The analysis is based on...
Source: http://arxiv.org/abs/1203.4086v2
Arxiv.org
by M. Arrayás; M. A. Fontelos; U. Kindelán
texts

eye 93

favorite 0

comment 0

We present the first analytical and numerical studies of the initial stage of the branching process based on an interface dynamics streamer model in the fully 3-D case. This model follows from fundamental considerations on charge production by impact ionization and balance laws, and leads to an equation for the evolution of the interface between ionized and non-ionized regions. We compare some experimental patterns with the numerically simulated ones, and give an explicit expression for the...
Source: http://arxiv.org/abs/1203.6790v1
Arxiv.org
by Kevin Heng; Pushkar Kopparla
texts

eye 94

favorite 0

comment 0

We investigate the stability of super Earth atmospheres around M stars using a 7-parameter, analytical framework. We construct stability diagrams in the parameter space of exoplanetary radius versus semi-major axis and elucidate the regions in which the atmospheres are stable against the condensation of their major constituents, out of the gas phase, on their permanent nightside hemispheres. We find that super Earth atmospheres which are nitrogen-dominated ("Earth-like") occupy a...
Source: http://arxiv.org/abs/1203.1922v3
Arxiv.org
by J. W. Maluf; F. F. Faria
texts

eye 69

favorite 0

comment 0

In this work a tetrad theory of gravity, invariant under conformal transformations, is investigated. The action of the theory is similar to the action of Maxwell's electromagnetism. The role of the electromagnetic gauge potential is played by the trace of the torsion tensor of the Weitzenb\"ock spacetime. It is shown that all static, spherically symmetric space-times, are solutions of the vacuum field equations. However, by fixing the gauge in the linearized form of the vacuum field...
Source: http://arxiv.org/abs/1203.0040v2
Arxiv.org
by L. D. Anderson; A. Zavagno; L. Deharveng; A. Abergel; F. Motte; Ph. Andre; J. -P. Bernard; S. Bontemps; M. Hennemann; T. Hill; J. A. Rodon; H. Roussel; D. Russeil
texts

eye 39

favorite 0

comment 0

Because of their relatively simple morphology, "bubble" HII regions have been instrumental to our understanding of star formation triggered by HII regions. With the far-infrared (FIR) spectral coverage of the Herschel satellite, we can access the wavelengths where these regions emit the majority of their energy through their dust emission. At Herschel wavelengths 70 micron to 500 micron, the emission associated with HII regions is dominated by the cool dust in their photodissociation...
Source: http://arxiv.org/abs/1203.5721v1
Arxiv.org
by A. Maleknejad; M. M. Sheikh-Jabbari
texts

eye 44

favorite 0

comment 0

In this work we revisit Wald's cosmic no-hair theorem in the context of accelerating Bianchi cosmologies for a generic cosmic fluid with non-vanishing anisotropic stress tensor and when the fluid energy momentum tensor is of the form of a cosmological constant term plus a piece which does not respect strong or dominant energy conditions. Such a fluid is the one appearing in inflationary models. We show that for such a system anisotropy may grow, in contrast to the cosmic no-hair conjecture. In...
Source: http://arxiv.org/abs/1203.0219v2
Arxiv.org
by J. de la Cruz Rodríguez; H. Socas-Navarro; M. Carlsson; J. Leenaarts
texts

eye 45

favorite 0

comment 0

The magnetic field of the quiet-Sun chromosphere remains a mystery for solar physicists. The reduced number of chromospheric lines are intrinsically hard to model and only a few of them are magnetically sensitive. In this work, we use a 3D numerical simulation of the outer layers of the solar atmosphere, to asses the reliability of non-LTE inversions, in this case applied to the Ca II 8542 \AA\ line. We show that NLTE inversions provide realistic estimates of physical quantities from synthetic...
Source: http://arxiv.org/abs/1203.4577v1
Arxiv.org
by Riku Klén; Ville Suomala
texts

eye 41

favorite 0

comment 0

We consider metrics on Euclidean domains $\Omega\subset\R^n$ that are induced by continuous densities $\rho\colon\Omega\rightarrow(0,\infty)$ and study the Hausdorff and packing dimensions of the boundary of $\Omega$ with respect to these metrics.
Source: http://arxiv.org/abs/1005.1808v3
Arxiv.org
texts

eye 55

favorite 0

comment 0

We show that for every mixing orthogonal representation $\pi : \Z \to \mathcal O(H_\R)$, the abelian subalgebra $\LL(\Z)$ is maximal amenable in the crossed product ${\rm II}_1$ factor $\Gamma(H_\R)\dpr \rtimes_\pi \Z$ associated with the free Bogoljubov action of the representation $\pi$. This provides uncountably many non-isomorphic $A$-$A$-bimodules which are disjoint from the coarse $A$-$A$-bimodule and of the form $\LL^2(M \ominus A)$ where $A \subset M$ is a maximal amenable masa in a...
Source: http://arxiv.org/abs/1203.6743v1
Arxiv.org
by J. D. Watson; S. Mondal; G. Gardner; G. A. Csáthy; M. J. Manfra
texts

eye 43

favorite 0

comment 0

We report on the growth and electrical characterization of a series of two-dimensional hole systems (2DHSs) used to study the density dependence of low temperature mobility in 20 nm GaAs/AlGaAs quantum wells. The hole density was controlled by changing the Al mole fraction and the setback of the delta-doping layer. We varied the density over a range from 1.8 $\times$ 10$^{10}$ cm$^{-2}$ to 1.9 $\times$ 10$^{11}$ cm$^{-2}$ finding a nonmonotonic dependence of mobility on density at T = 0.3 K....
Source: http://arxiv.org/abs/1203.4312v1
Arxiv.org
texts

eye 32

favorite 0

comment 0

Learning how proteins fold will hardly have any impact in the way conventional -- active site centered -- drugs are designed. On the other hand, this knowledge is proving instrumental in defining a new paradigm for the identification of drugs against any target protein: folding inhibition. Targeting folding renders drugs less prone to elicit spontaneous genetic mutations which in many cases, notably in connection with viruses like the Human Immunodeficiency Virus (HIV), can block therapeutic...
Source: http://arxiv.org/abs/1203.3315v1
Arxiv.org
texts

eye 149

favorite 0

comment 0

We show that the distribution of luminosities of Brightest Cluster Galaxies in an SDSS-based group catalog suggests that BCG luminosities are just the statistical extremes of the group galaxy luminosity function. This latter happens to be very well approximated by the all-galaxy luminosity function (restricted to Mr
Source: http://arxiv.org/abs/1107.3652v2
Arxiv.org
texts

eye 46

favorite 0

comment 0

We consider the zero dissipation limit of the full compressible Navier-Stokes equations with Riemann initial data in the case of superposition of two rarefaction waves and a contact discontinuity. It is proved that for any suitably small viscosity $\varepsilon$ and heat conductivity $\kappa$ satisfying the relation \eqref{viscosity}, there exists a unique global piecewise smooth solution to the compressible Navier-Stokes equations. Moreover, as the viscosity $\varepsilon$ tends to zero, the...
Source: http://arxiv.org/abs/1203.1230v1
Arxiv.org
by Raffaella Schneider; Kazuyuki Omukai; Marco Limongi; Andrea Ferrara; Ruben Salvaterra; Alessandro Chieffi; Simone Bianchi
texts

eye 93

favorite 0

comment 0

The relative importance of metals and dust grains in the formation of the first low-mass stars has been a subject of debate. The recently discovered Galactic halo star SDSS J102915+172927 (Caffau et al. 2011) has a mass less than 0.8 Msun and a metallicity of Z = 4.5 10^{-5} Zsun. We investigate the origin and properties of this star by reconstructing the physical conditions in its birth cloud. We show that the observed elemental abundance trend of SDSS J102915+172927 can be well fitted by the...
Source: http://arxiv.org/abs/1203.4234v1
Arxiv.org
by Rajeev K. Shakya; Yatindra Nath Singh; Nishchal K. Verma
texts

eye 33

favorite 0

comment 0

We study the problem of medium access control in domain of event-driven wireless sensor networks (WSNs). In this kind of WSN, sensor nodes send data to sink node only when an event occurs in the monitoring area. The nodes in this kind of WSNs encounter correlated traffic as a subset of nodes start sending data by sensing a common event simultaneously. We wish to rethink of medium access control (MAC) for this type of traffic characteristics. For WSNs, many existing MAC protocols utilize the...
Source: http://arxiv.org/abs/1203.5874v2
Arxiv.org
by Mrinal Kanti Roychowdhury
texts

eye 109

favorite 0

comment 0

The cookie-cutter-like set is defined as the limit set of a sequence of classical cookie-cutter mappings. For this cookie-cutter-like set first we have determined the topological pressure function, and then by Banach limit we have determined a unique Borel probability measure $\mu_h$ with the support the cookie-cutter-like set $E$. With the topological pressure and the measure $\mu_h$, we have shown that the fractal dimensions such as the Hausdorff dimension, the packing dimension and the...
Source: http://arxiv.org/abs/1203.2724v3
Arxiv.org
texts

eye 104

favorite 0

comment 0

The game of chess as always been viewed as an iconic representation of intellectual prowess. Since the very beginning of computer science, the challenge of being able to program a computer capable of playing chess and beating humans has been alive and used both as a mark to measure hardware/software progresses and as an ongoing programming challenge leading to numerous discoveries. In the early days of computer science it was a topic for specialists. But as computers were democratized, and the...
Source: http://arxiv.org/abs/1203.3434v1
Arxiv.org
texts

eye 53

favorite 0

comment 0

The maximally extended Reissner--Nordstr\"om (RN) manifold with $e^2 < m^2$ begs for attaching a material source to it that would preserve the infinite chain of asymptotically flat regions and evolve through the wormhole between the RN singularities. So far, the attempts were discouraging. Here we try one more possible source -- a solution found by Ruban in 1972 that is a charged generalisation of an inhomogeneous Kantowski--Sachs-type dust solution. It can be matched to the RN...
Source: http://arxiv.org/abs/1107.4897v3
Arxiv.org
by Octavio A. González-Estrada; Sundararajan Natarajan; Juan José Ródenas; Hung Nguyen-Xuan; Stéphane P. A. Bordas
texts

eye 42

favorite 0

comment 0

An error control technique aimed to assess the quality of smoothed finite element approximations is presented in this paper. Finite element techniques based on strain smoothing appeared in 2007 were shown to provide significant advantages compared to conventional finite element approximations. In particular, a widely cited strength of such methods is improved accuracy for the same computational cost. Yet, few attempts have been made to directly assess the quality of the results obtained during...
Source: http://arxiv.org/abs/1203.1278v1
Arxiv.org
by T. J. Davidge; A. W. McConnachie; M. A. Fardal; J. Fliri; D. Valls-Gabaud; S. C. Chapman; G. F. Lewis; R. M. Rich
texts

eye 60

favorite 0

comment 0

We examine the star-forming history (SFH) of the M31 disk during the past few hundred Myr. The luminosity functions (LFs) of main sequence stars at distances R_GC > 21 kpc (i.e. > 4 disk scale lengths) are matched by models that assume a constant star formation rate (SFR). However, at smaller R_GC the LFs suggest that during the past ~10 Myr the SFR was 2 - 3 times higher than during the preceding ~100 Myr. The rings of cool gas that harbor a significant fraction of the current...
Source: http://arxiv.org/abs/1203.6081v1
Arxiv.org
texts

eye 80

favorite 0

comment 0

We have investigated the six most tightly bound states of each of the atoms, helium and lithium, in intense magnetic fields. In this regard, we report new data for two new states of lithium that have not been studied thus far in the literature. The energy levels of these first few low-lying states are calculated in this study employing a pseudospectral method as the computational tool. The methodology involves computing the eigenvalues and eigenvectors of the generalized two-dimensional...
Source: http://arxiv.org/abs/1203.3437v1
Arxiv.org
by A. Müller; S. Schippers; R. A. Phaneu; S. W. J. Scully; A. Aguilar; C. Cisneros; M. F. Gharaibeh; A. S. Schlachter; B. M. McLaughlin
texts

eye 46

favorite 0

comment 0

Absolute cross sections for the K-shell photoionization of ground-state Li-like boron [B$^{2+}$(1s$^2$2s $^2$S)] ions were measured by employing the ion-photon merged-beams technique at the Advanced Light Source synchrotron radiation facility. The energy ranges 197.5--200.5 eV, 201.9--202.1 eV of the [1s(2s\,2p)$^3$P]$^2$P${\rm ^o}$ and [1s(2s\,2p)$^1$P] $^2$P${\rm ^o}$ resonances, respectively, were investigated using resolving powers of up to 17\,600. The energy range of the experiments was...
Source: http://arxiv.org/abs/1203.5375v1
Arxiv.org
texts

eye 85

favorite 0

comment 0

The autocorrelation function of the Langevin force in the model introduced in the cited paper is calculated and verified to be correct.
Source: http://arxiv.org/abs/1203.4512v1
Arxiv.org
texts

eye 30

favorite 0

comment 0

A unit evolution step of discrete-time quantum walks is determined by both a coin-flip operator and a position-shift operator. The behavior of quantum walkers after many steps delicately depends on the coin-flip operator and an initial condition of the walk. To get the behavior, a lot of long-time limit distributions for the quantum walks starting with a localized initial state have been derived. In the present paper, we compute limit distributions of a 2-state quantum walk with a non-localized...
Source: http://arxiv.org/abs/1203.5396v3
Arxiv.org
by Kee-Hoon Kim; Hyun-Bae Jeon; Jong-Seon No; Dong-Joon Shin
texts

eye 66

favorite 0

comment 0

In this paper, a new peak-to-average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) is proposed based on the selected mapping (SLM) scheme. The proposed SLM scheme generates alternative OFDM signal sequences by cyclically shifting the connections in each subblock at an intermediate stage of inverse fast Fourier transform (IFFT). Compared with the conventional SLM scheme, the proposed SLM scheme achieves similar PAPR reduction performance with much...
Source: http://arxiv.org/abs/1203.5156v1
Arxiv.org
by Mancho Manev; Miroslava Ivanova
texts

eye 40

favorite 0

comment 0

The canonical-type connection on the almost contact manifolds with B-metric is constructed. It is proved that its torsion is invariant with respect to a subgroup of the general conformal transformations of the almost contact B-metric structure. The basic classes of the considered manifolds are characterized in terms of the torsion of the canonical-type connection.
Source: http://arxiv.org/abs/1203.0137v3
Consider the following forest-fire process on a connected graph. Each site of the graph can be either occupied or vacant. A vacant site becomes occupied with rate 1. A site is ignited with rate lambda, and its whole occupied cluster burns instantaneously. The purpose of this paper is to show the existence of a stationary distribution for forest-fire processes on Z^d, for d >= 2. We define a distribution as a limit of a sequence of invariant distributions of finite volume forest-fire...
Source: http://arxiv.org/abs/1203.5533v1
Arxiv.org
by Curtis Menton
texts

eye 29

favorite 0

comment 0

We study the behavior of Range Voting and Normalized Range Voting with respect to electoral control. Electoral control encompasses attempts from an election chair to alter the structure of an election in order to change the outcome. We show that a voting system resists a case of control by proving that performing that case of control is computationally infeasible. Range Voting is a natural extension of approval voting, and Normalized Range Voting is a simple variant which alters each vote to...
Source: http://arxiv.org/abs/1005.5698v3
Arxiv.org
texts

eye 70

favorite 0

comment 0

In this paper, a study of random times on filtered probability spaces is undertaken. The main message is that, as long as distributional properties of optional processes up to the random time are involved, there is no loss of generality in assuming that the random time is actually a randomized stopping time. This perspective has advantages in both the theoretical and practical study of optional processes up to random times. Applications are given to the stochastic behavior of processes up to...
Source: http://arxiv.org/abs/1007.1124v3
Arxiv.org
by Alan H. Guth; Yasunori Nomura
texts

eye 52

favorite 0

comment 0

The eternally inflating multiverse provides a consistent framework to understand coincidences and fine-tuning in the universe. As such, it provides the possibility of finding another coincidence: if the amount of slow-roll inflation was only slightly more than the anthropic threshold, then spatial curvature might be measurable. We study this issue in detail, particularly focusing on the question: "If future observations reveal nonzero curvature, what can we conclude?" We find that...
Source: http://arxiv.org/abs/1203.6876v2
Arxiv.org
texts

eye 58

favorite 0

comment 0

Suppose M is a non-compact connected n-manifold without boundary, DD(M) is the group of C^\infty-diffeomorphisms of M endowed with the Whitney C^\infty-topology and DD_0(M) is the identity connected component of DD(M), which is an open subgroup in the group DD_c(M) \subset DD(M) of compactly supported diffeomorphisms of M. It is shown that DD_0(M) is homeomorphic to N \times IR^\infty for an l_2-manifold N whose topological type is uniquely determined by the homotopy type of DD_0(M). For...
Source: http://arxiv.org/abs/1005.1789v2
Arxiv.org
texts

eye 56

favorite 0

comment 0

Differential rotation induced by the r-mode instability can generate very strong toroidal fields in the core of accreting, millisecond spinning neutron stars. We introduce explicitly the magnetic damping term in the evolution equations of the r-modes and solve them numerically in the Newtonian limit, to follow the development and growth of the internal magnetic field. We show that the strength of the latter can reach large values, $B \sim 10^{14} $ G, in the core of the fastest accreting...
Source: http://arxiv.org/abs/1203.0891v2
Arxiv.org
by J. Cacoq; B. de la Calle Ysern. G. López Lagomasino
texts

eye 36

favorite 0

comment 0

We give necessary and sufficient conditions for the convergence with geometric rate of the common denominators of simultaneous rational interpolants with a bounded number of poles. The conditions are expressed in terms of intrinsic properties of the system of functions used to build the approximants. Exact rates of convergence for these denominators and the simultaneous rational approximants are provided.
Source: http://arxiv.org/abs/1203.4947v1
Arxiv.org
texts

eye 48

favorite 0

comment 0

High transmission plateaus exist widely in the logarithmic transmission spectra of localized systems. Their physical origins are short chains of coupled-localized-states embedded inside the localized system, which are dubbed as "short necklace states". In this work, we define the essential quantities and then, based on these quantities, we investigate the short necklace states' properties statistically and quantitatively. Two different approaches are utilized and the results from them...
Source: http://arxiv.org/abs/1203.1713v1
Arxiv.org
texts

eye 49

favorite 0

comment 0

This article announces joint work with Frank Connolly and Jim Davis. We generalize our classification of pseudo-free involutions on the n-torus, by studying the action of the associated infinite group with torsion in the universal cover. Included is a non-Riemannian example obtained from the restriction of the action of a Coxeter group on a CAT(0) manifold.
Source: http://arxiv.org/abs/1203.4650v2
Arxiv.org
texts

eye 98

favorite 0

comment 0

Among all restricted integer compositions with at most $m$ parts, each of which has size at most $l$, choose one uniformly at random. Which integer does this composition represent? In the current note, we show that underlying distribution is, for large $m$ and $l$, approximately normal with mean value $\frac{ml}{2}$.
Source: http://arxiv.org/abs/1203.0690v1
We present the results of a search for pair production of scalar bottom quarks ($\tilde b_1$) and scalar third-generation leptoquarks ($LQ_3$) in a data sample of 5.2 $fb^{-1}$ collected by the D0 experiment at the Tevatron, the $p\bar{p}$ collider at Fermilab. We assume that sbottoms decay to a neutralino ($\tilde \chi^0_1$) and a b quark, and we set 95% C.L. lower limits on their production in the ($m_{\tilde b_1}$, $m_{\tilde \chi^0_1}$) mass plane such that $m_{\tilde b_1} > 247$ GeV for...
Source: http://arxiv.org/abs/1203.6800v1
Arxiv.org
by Maxim Perelstein; Bibhushan Shakya
texts

eye 35

favorite 0

comment 0

We study theoretical implications of direct dark matter searches in the minimal supersymmetric standard model (MSSM). We assume that no accidental cancellations occur in the spin-independent elastic neutralino-quark scattering cross section, but do not impose any relations among the weak-scale MSSM parameters. We show that direct detection cross section below 10^-44 cm^2 requires the lightest supersymmetric particle (LSP) neutralino to be close to either a pure gaugino or pure Higgsino limit,...
Source: http://arxiv.org/abs/1107.5048v4
Arxiv.org
by Lars Grüne; Jürgen Pannek; Karl Worthmann
texts

eye 52

favorite 0

comment 0

For networked systems, the control law is typically subject to network flaws such as delays and packet dropouts. Hence, the time in between updates of the control law varies unexpectedly. Here, we present a stability theorem for nonlinear model predictive control with varying control horizon in a continuous time setting without stabilizing terminal constraints or costs. It turns out that stability can be concluded under the same conditions as for a (short) fixed control horizon.
Source: http://arxiv.org/abs/1203.6785v2
Arxiv.org
by Jay Gopalakrishnan; Weifeng Qiu
texts

eye 81

favorite 0

comment 0

In this work we give a complete error analysis of the Discontinuous Petrov Galerkin (DPG) method, accounting for all the approximations made in its practical implementation. Specifically, we consider the DPG method that uses a trial space consisting of polynomials of degree $p$ on each mesh element. Earlier works showed that there is a "trial-to-test" operator $T$, which when applied to the trial space, defines a test space that guarantees stability. In DPG formulations, this operator...
Source: http://arxiv.org/abs/1107.4293v2
Arxiv.org
texts

eye 39

favorite 0

comment 0

By separating the gluon field into physical and pure-gauge components, the usual Poincar\'e subalgebra for an interacting system can be reconciled with gauge-invariance when decomposing the total rotation and translation generators of QCD into quark and gluon parts. The gauge-invariant quark/gluon parts act as the generators for the gauge-invariant physical component of the quark/gluon field, not the full quark/gluon field which also contains the gauge degrees of freedom. We clarify that the...
Source: http://arxiv.org/abs/1203.1288v1
Arxiv.org
by Lauren Anderson; Eric Aubourg; Stephen Bailey; Dmitry Bizyaev; Michael Blanton; Adam S. Bolton; J. Brinkmann; Joel R. Brownstein; Angela Burden; Antonio J. Cuesta; Luiz N. A. da Costa; Kyle S. Dawson; Roland de Putter; Daniel J. Eisenstein; James E. Gunn; Hong Guo; Jean-Christophe Hamilton; Paul Harding; Shirley Ho; Klaus Honscheid; Eyal Kazin; D. Kirkby; Jean-Paul Kneib; Antione Labatie; Craig Loomis; Robert H. Lupton; Elena Malanushenko; Viktor Malanushenko; Rachel Mandelbaum; Marc Manera;...
texts

eye 101

favorite 0

comment 0

We present measurements of galaxy clustering from the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III (SDSS-III). These use the Data Release 9 (DR9) CMASS sample, which contains 264,283 massive galaxies covering 3275 square degrees with an effective redshift z=0.57 and redshift range 0.43 < z < 0.7. Assuming a concordance Lambda-CDM cosmological model, this sample covers an effective volume of 2.2 Gpc^3, and represents the largest sample...
Source: http://arxiv.org/abs/1203.6594v1
Arxiv.org
texts

eye 42

favorite 0

comment 0

Recent works [Y.D. Chong {\it et al.}, Phys. Rev. Lett. {\bf 105}, 053901 (2010); W. Wan {\it et al.}, Science {\bf 331}, 889 (2011)] have shown that the time-reversed process of lasing at threshold realizes a coherent perfect absorber (CPA). In a CPA, a lossy medium in an optical cavity with a specific degree of dissipation, equal in modulus to the gain of the lasing medium, can perfectly absorb coherent optical waves at discrete frequencies that are the time-reversed counterpart of the lasing...
Source: http://arxiv.org/abs/1203.5033v2
Arxiv.org
by Delio Mugnolo; Robin Nittka; Olaf Post
texts

eye 131

favorite 0

comment 0

Convergence of operators acting on a given Hilbert space is an old and well studied topic in operator theory. The idea of introducing a related notion for operators acting on arying spaces is natural. However, it seems that the first results in this direction have been obtained only recently, to the best of our knowledge. Here we consider sectorial operators on scales of Hilbert spaces. We define a notion of convergence that generalises convergence of the resolvents in operator norm to the case...
Source: http://arxiv.org/abs/1007.3932v2
Arxiv.org
by P. S. Burada; B. Lindner
texts

eye 51

favorite 0

comment 0

We study the dynamics of an active Brownian particle with a nonlinear friction function located in a spatial cubic potential. For strong but finite damping, the escape rate of the particle over the spatial potential barrier shows a nonmonotonic dependence on the noise intensity. We relate this behavior to the fact that the active particle escapes from a limit cycle rather than from a fixed point and that a certain amount of noise can stabilize the sojourn of the particle on this limit cycle.
Source: http://arxiv.org/abs/1203.6814v1
Arxiv.org
texts

eye 120

favorite 0

comment 0

We are considering iterative derivations on the function field L of abelian schemes in positive characteristic p>0, and give conditions when the torsion group schemes of this abelian scheme occur as ID-automorphism groups, i.e. are the ID-Galois groups of L over certain ID-subfields. For an explicit example, we even give a construction of (a family of) such iterative derivations.
Source: http://arxiv.org/abs/1203.6198v1
Arxiv.org
by Toby S. Cubitt; Jens Eisert; Michael M. Wolf
texts

eye 46

favorite 0

comment 0

The behavior of any physical system is governed by its underlying dynamical equations. Much of physics is concerned with discovering these dynamical equations and understanding their consequences. In this work, we show that, remarkably, identifying the underlying dynamical equation from any amount of experimental data, however precise, is a provably computationally hard problem (it is NP-hard), both for classical and quantum mechanical systems. As a by-product of this work, we give...
Source: http://arxiv.org/abs/1005.0005v2
Arxiv.org
texts

eye 44

favorite 0

comment 0

The Hamiltonian analysis for the Euler and Second-Chern classes is performed. We show that, in spite of the fact that the Second-Chern and Euler invariants give rise to the same equations of motion, their corresponding symplectic structures on the phase space are different, therefore, one can expect different quantum formulations. In addition, the symmetries of actions written as a BF-like theory that lead to Yang-Mills equations of motion are studied. A close relationship with the results...
Source: http://arxiv.org/abs/1203.5369v1
Arxiv.org
by Inti Sodemann; D. A. Pesin; A. H. MacDonald
texts

eye 110

favorite 0

comment 0

We estimate the strength of interaction-enhanced coherence between two graphene or topological insulator surface-state layers by solving imaginary-axis gap equations in the random phase approximation. Using a self-consistent treatment of dynamic screening of Coulomb interactions in the gapped phase, we show that the excitonic gap can reach values on the order of the Fermi energy at strong interactions. The gap is discontinuous as a function of interlayer separation and effective fine structure...
Source: http://arxiv.org/abs/1203.3594v1
Arxiv.org
texts

eye 40

favorite 0

comment 0

The wetting properties of solid substrates with macroscopic random roughness are considered as a function of the microscopic contact angle of the wetting liquid and its partial pressure in the surrounding gas phase. It is shown that Wenzel prewetting, which has been recently predicted for a rather wide class of roughness pro?les derived from Gaussian random processes by a general distortion procedure, should in fact be ubiquitous and prevail under even much milder conditions. The well-known...
Source: http://arxiv.org/abs/1203.5215v1
Arxiv.org
texts

eye 39

favorite 0

comment 0

We stabilized the frequencies of two independent Nd:YAG lasers to two adjacent longitudinal modes of a high-finesse Fabry-P\'erot resonator and obtained a beat frequency instability of 6.3 mHz at an integration time of 40 s. Referred to a single laser, this is $1.6\times10^{-17}$ relative to the laser frequency, and $1.3\times10^{-6}$ relative to the full width at half maximum of the cavity resonance. The amplitude spectrum of the beat signal had a FWHM of 7.8 mHz. This stable frequency locking...
Source: http://arxiv.org/abs/1203.6247v1
Arxiv.org
by Laurie Urban; George Rieke; Kate Su; David E. Trilling
texts

eye 57

favorite 0

comment 0

We use Spitzer Space Telescope 24 {\mu}m data to search for debris disks among 122 AFGKM stars from the \sim 670 Myr clusters Hyades, Coma Ber, and Praesepe, utilizing a number of advances in data reduction and determining the intrinsic colors of main sequence stars. For our sample, the 1{\sigma} dispersion about the main sequence V-K, K-[24] locus is approximately 3.1%. We identify seven debris disks at 10% or more (\geq 3{\sigma} confidence level) above the expected K-[24] for purely...
Source: http://arxiv.org/abs/1203.0027v1
Arxiv.org
by Gonzalo A. Alvarez; Alexandre M. Souza; Dieter Suter
texts

eye 58

favorite 0

comment 0

The loss of quantum information due to interaction with external degrees of freedom, which is known as decoherence, remains one of the main obstacles for large-scale implementations of quantum computing. Accordingly, different measures are being explored for reducing its effect. One of them is dynamical decoupling (DD) which offers a practical solution because it only requires the application of control pulses to the system qubits. Starting from basic DD sequences, more sophisticated schemes...
Source: http://arxiv.org/abs/1203.0252v1
Arxiv.org
texts

eye 62

favorite 0

comment 0

A new zerofree region of the Riemann Zeta-function $\zeta$ is identified by using Tur\'an's localization criterion linking zeros of $\zeta$ with uniform local suprema of sets of Dirichlet polynomials expanded over the primes. The proof is based on a randomization argument. An estimate for local extrema for some finite families of shifted Dirichlet polynomials, % associated to linearly independent sequences of reals is established by preliminary considering their local increment properties, by...
Source: http://arxiv.org/abs/1005.3932v2