September 2009 arXiv papers — page 17

C. Barcelo, S. Liberati, S. Sonego, M. Visser

The existence of extremely dark and compact astronomical bodies is by now a well established observational fact. On the other hand, classical General Relativity predicts the existence of black holes which fit very well with the observations, but do lead to important conceptual problems. In this contribution we ask ourselves the straightforward question: Are

Franziska Piontek, Matthias Steinmetz

We conduct a systematic study of the angular momentum problem in numerical simulations of disk galaxy formation. We investigate the role of numerical resolution using a semi-cosmological setup which combines an efficient use of the number of particles in an isolated halo while preserving the hierarchical build-up of the disk through the merging of clumps. We

Francesco Malaspina

Here we define the concept of $L$-regularity for coherent sheaves on the Grassmannian G(1,4) as a generalization of Castelnuovo-Mumford regularity on ${\bf{P}^n}$. In this setting we prove analogs of some classical properties. We use our notion of $L$-regularity in order to prove a splitting criterion for rank 2 vector bundles with only a finite number of va

Mariano de Souza, Daniel Hofmann, Pascale Foury-Leylekian, Alec Moradpour

We report results of high-resolution measurements of the \emph{c$^*$}-axis expansivity ($α_{c^{*}}$) at the charge-ordering (CO) transition for the quasi-1D (TMTTF)$_{2}$X compounds with X = SbF$_6$ and Br and make a comparison with previous results for the X = PF$_6$ and AsF$_6$ salts. For X = SbF$_6$, due to the screening of the long-range Coulomb forces,

B. Meirose

In this paper we discuss briefly the correlation between fake missing transverse energy and jets pointing to crack regions in the ATLAS calorimeters.

Josep M. Pons

In field theory, as well as in mechanics, the substitution of some fields in terms of other fields at the level of the action raises an issue of consistency with respect to the equations of motion. We discuss this issue and give an expression which neatly displays the difference between doing the substitution at the level of the Lagrangian or at the level of

Donato Bini, Andrea Geralico, Orlando Luongo, Hernando Quevedo

An exact solution of Einstein's field equations in empty space first found in 1985 by Quevedo and Mashhoon is analyzed in detail. This solution generalizes Kerr spacetime to include the case of matter with arbitrary mass quadrupole moment and is specified by three parameters, the mass $M$, the angular momentum per unit mass $a$ and the quadrupole parameter $

David S Score, Marzook Alshammari, Qi Feng, Harry J Blythe

Multilayer films of ZnO with Co were deposited on glass substrates then annealed in a vacuum. The magnetisation of the films increased with annealing but not the magnitude of the magneto-optical signals. The dielectric functions for the films were calculated using the MCD spectra. A Maxwell Garnett theory of a metallic Co/ZnO mixture is presented. The extent

D. C. Rapaport

Results from molecular dynamics simulations of simple, structured particles capable of self-assembling into polyhedral shells are described. The analysis focuses on the growth histories of individual shells in the presence of an explicit solvent and the nature of the events along their growth pathways; the results provide further evidence of the importance o

Daniel R. Terno

The gravity-scalar field system in spherical symmetry provides a natural setting for exploring gravitational collapse and its aftermath in quantum gravity. In a canonical approach, we give constructions of the constraint and Hamiltonian operators. Matter-gravity entanglement is an inherent feature of physical states, whether or not there is a black hole. Mat

Jakub Onufry Wojtaszczyk

Negative association for a family of random variables $(X_i)$ means that for any coordinate--wise increasing functions $f,g$ we have $$\E f(X_{i_1},...,X_{i_k}) g(X_{j_1},...,X_{j_l}) \leq \E f(X_{i_1},...,X_{i_k}) \E g(X_{j_1},...,X_{j_l})$$ for any disjoint sets of indices $(i_m)$, $(j_n)$. It is a way to indicate the negative correlation in a family of ra

Wei Wang, Yue-Long Shen, Cai-Dian Lu

The existence of a glueball has been a tough work for many years study. Utilizing the well developed QCD theory for $B$ meson decays, we propose a new way to identify whether a scalar glueball existed or not. In the presence of mixing between glueballs and ordinary scalar mesons, we explore the possibility to extract the mixing parameters from semileptonic B

A. Boselli, G. Gavazzi

Pre-processing within small groups has been proposed to explain several of the properties of galaxies inhabiting rich clusters. The aim of the present work is to see whether pre-processing is acting in the nearby universe, where the structures that are merging to form rich clusters are rather large and massive. We study the HI gas properties of a large sampl

A. Dantan, M. Albert, J. P. Marler, P. F. Herskind

We present an investigation of the coherent coupling of various transverse field modes of an optical cavity to ion Coulomb crystals. The obtained experimental results, which include the demonstration of identical collective coupling rates for different transverse modes of a cavity field to ions in the same large Coulomb crystal, are in excellent agreement wi

Arnold O. Benz, Christian Monstein, Michael Beverland, Hansueli Meyer

A new multichannel spectrometer, Phoenix-3, is in operation having capabilities to observe solar flare radio emissions in the 0.1 - 5 GHz range at an unprecedented spectral resolution of 61.0 kHz with high sensitivity. The present setup for routine observations allows measuring circular polarization, but requires a data compression to 4096 frequency channels

L. de Francesco Albasini, N. Sabadini, R. F. C. Walters

We develop further the algebra of cospans and spans of graphs introduced by Katis, Sabadini and Walters for the sequential and parallel composition of processes, adding here data types.

Tsuguo Mogami

The gauge field theories are usually quantized by fixing gauge. In this paper, we propose a new formalism that quantizes gauge fields without gauge fixing but naturally follows canonical formalism. New physical implications will follow.

Alvaro Liendo

A T-variety is an algebraic variety X with an effective regular action of an algebraic torus T. Altmann and Hausen gave a combinatorial description of an affine T-variety X by means of polyhedral divisors. In this paper we compute the higher direct images of the structure sheaf of a desingularization of X in terms of this combinatorial data. As a consequence

Selma Yildirim Yolcu

In this article we improve a lower bound for $\sum_{j=1}^kβ_j$ (a Berezin-Li-Yau type inequality) in [E. M. Harrell II and S. Yildirim Yolcu, Eigenvalue inequalities for Klein-Gordon Operators, J. Funct. Analysis, 256(12) (2009) 3977-3995]. Here $β_j$ denotes the $j$th eigenvalue of the Klein Gordon Hamiltonian $H_{0,Ω}=|p|$ when restricted to a bounded set

Hansheng Diao, Cesar E. Silva

In this paper, we construct a digraph structure on $p$-adic dynamical systems defined by rational functions. We study the conditions under which the functions are measure-preserving, invertible and isometric, ergodic, and minimal on invariant subsets, by means of graph theoretic properties.

Yaming Yu

The bivariate distribution with exponential conditionals (BEC) is introduced by Arnold and Strauss [Bivariate distributions with exponential conditionals, J. Amer. Statist. Assoc. 83 (1988) 522--527]. This work presents a simple and fast algorithm for simulating random variates from this density.

Yaming Yu

We present an entropy comparison result concerning weighted sums of independent and identically distributed random variables.

Shun-Qing Shen

We study the quantum Hall effect in the surface states of topological insulator in the presence of a perpendicular magnetic field in the framework of edge states. Motion of Dirac fermions will form descrete Landau levels, among which a fully saturated zero mode will have different behaviors near the boundary according to the sign of the effective mass for Di

John M. Carpenter, Eric E. Mamajek, Lynne A. Hillenbrand, Michael R. Meyer

We present MIPS 24um and 70um photometry for 205 members of the Upper Scorpius OB Association. These data are combined with published MIPS photometry for 15 additional association members to assess the frequency of circumstellar disks around 5 Myr old stars with spectral types between B0 and M5. Twelve stars have a detectable 70um excess, each of which also

T. Laskar, A. C. Fabian, K. M. Blundell, M. C. Erlund

We report XMM-Newton observations of three FR II radio galaxies at redshifts between 0.85 and 1.34, which show extended diffuse X-ray emission within the radio lobes, likely due to inverse-Compton up-scattering of the cosmic microwave background. Under this assumption, through spectrum-fitting together with archival VLA radio observations, we derive an indep

Tiago M. D. Pereira, Martin Asplund, Dan Kiselman

We present results from a series of observational tests to 3D and 1D solar models. In particular, emphasis is given to the line formation of atomic oxygen lines, used to derive the much debated solar oxygen photospheric abundance. Using high-quality observations obtained with the Swedish Solar Telescope (SST) we study the centre-to-limb variation of the O I

Guy Ramon, Xuedong Hu

The effects of a nearby two-level charge fluctuator on a double-dot two-spin qubit are studied theoretically. Assuming no direct tunneling between the charge fluctuator and the qubit quantum dots, the Coulomb couplings between the qubit orbital states and the fluctuator are calculated within the Hund-Mulliken framework to quadrupole-quadrupole order in a mul

Minnie Y. Mao, Ray P. Norris, Rob Sharp, Jim E. J. Lovell

The Australia Telescope Large Area Survey (ATLAS), which is the widest deep field radio survey so far attempted, aims to probe the evolution of radio galaxies out to the edge of the Universe. Using AAOmega on the Anglo-Australian Telescope we have successfully obtained spectroscopic redshifts for 395 of the ATLAS radio galaxies. Coupled with 169 redshifts fr

S. Alexander, R. Bishop, R. Ghrist

We show how circumradius and asymptotic behavior of curves in CAT(0) and CAT(K) spaces(K>0) are controlled by growth rates of total curvature. We apply our results to pursuit and evasion games of capture type with simple pursuit motion, generalizing results that are known for convex Euclidean domains, and obtaining results that are new for convex Euclidean d

L. Grunenfelder

A recent result of ours [GM] shows that all Hopf algebra liftings of a given diagram in the sense of Andruskiewitsch and Schneider are cocycle deformations of each other. Here we develop a "non-abelian" cohomology theory, which gives a method for an explicit description of cocycles relevant to the lifting process.

Francesco Shankar, Gregory R. Sivakoff, Marianne Vestergaard, Xinyu Dai

We cross-correlate the SDSS DR3 quasar sample with FIRST and the Vestergaard et al. black hole (BH) mass sample to compare the mean accretion histories of optical and radio quasars. We find significant statistical evidence that radio quasars have a higher mean Eddington ratio Lambda at z > 2 with respect to optical quasars, while the situation is clearly rev

Thomas S. Levi, Joris Raeymaekers, Dieter Van den Bleeken, Walter Van Herck

We show that M-theory admits a supersymmetric compactification to the Godel universe of the form Godel3 x S2 x CY3. We interpret this geometry as coming from the backreaction of M2-branes wrapping the S2 in an AdS3 x S2 x CY3 flux compactification. In the black hole deconstruction proposal similar states give rise to the entropy of a D4-D0 black hole. The sy

R. J. Bouwens, G. D. Illingworth, M. Franx, R-R. Chary

We provide a systematic measurement of the rest-frame UV continuum slope beta over a wide range in redshift (z~2-6) and rest-frame UV luminosity (0.1-2L*) to improve estimates of the SFR density at high redshift. We utilize the deep optical and infrared data (ACS/NICMOS) over the CDF-S and HDF-N GOODS fields, as well as the UDF for our primary UBVi "drop

A. G. Ramm

Sufficient conditions are given for a hard implicit function theorem to hold. The result is established by an application of the Dynamical Systems Method (DSM). It allows one to solve a class of nonlinear operator equations in the case when the Fréchet derivative of the nonlinear operator is a smoothing operator, so that its inverse is an unbounded operator.

J. Mendez-Abreu, J. A. L. Aguerri, S. Zarattini, R. Sanchez-Janssen

Galaxy mergers and interactions are mechanisms which could drive the formation of bars. Therefore, we could expect that the fraction of barred galaxies increases with the local density. Here we show the first results of an extensive search for barred galaxies in different environments. We conclude that the bar fraction on bright (L>L*) field, Virgo, and Coma

Jean-Philippe Lessard

An old conjecture in delay equations states that Wright's equation \[ y'(t)= - αy(t-1) [ 1+y(t)], α\in \mathbb{R} \] has a unique slowly oscillating periodic solution (SOPS) for every parameter value $α>π/2$. We reformulate this conjecture and we use a method called validated continuation to rigorously compute a global continuous branch of SOPS of Wr

M. A. Zubkov

The lattice Weinberg - Salam model without fermions is investigated numerically for the realistic choice of bare coupling constants correspondent to the value of the Weinberg angle $θ_W \sim 30^o$, and the fine structure constant $α\sim {1/100}$. On the phase diagram there exists the vicinity of the phase transition between the physical Higgs phase and the u

David Estrada, Sumit Dutta, Albert Liao, Eric Pop

We describe a pulsed measurement technique to suppress hysteresis for carbon nanotube (CNT) device measurements in air, vacuum, and over a wide temperature range (80-453 K). Varying the gate pulse width and duty cycle probes the relaxation times associated with charge trapping near the CNT, found to be up to the 0.1-10 s range. Longer off times between volta

Behnaz Bozorgui, Maya Sen, William L. Miller, Josep C. Pamies

We report molecular dynamics simulations of a system of repulsive, polymer-tethered colloidal particles. We use an explicit polymer model to explore how the length and the behavior of the polymer (ideal or self-avoiding) affect the ability of the particles to organize into ordered structures when the system is compressed to moderate volume fractions. We find

Stephen Bigelow, Scott Morrison, Emily Peters, Noah Snyder

We construct a new subfactor planar algebra, and as a corollary a new subfactor, with the `extended Haagerup' principal graph pair. This completes the classification of irreducible amenable subfactors with index in the range $(4,3+\sqrt{3})$, which was initiated by Haagerup in 1993. We prove that the subfactor planar algebra with these principal graphs i

Z. Zhu, A. Aharony, O. Entin-Wohlman, P. C. E. Stamp

We study the dynamics of pure phase decoherence for a particle hopping around an N-site ring, coupled both to a spin bath and to an Aharonov-Bohm flux which threads the ring. Analytic results are found for the dynamics of the influence functional and of the reduced density matrix of the particle, both for initial single wave-packet states, and for states spl

Amish J. Patel, David Chandler

We use molecular dynamics simulations of the SPC-E model of liquid water to derive probability distributions for water density fluctuations in probe volumes of different shapes and sizes, both in the bulk as well as near hydrophobic and hydrophilic surfaces. To obtain our results, we introduce a biased sampling of coarse-grained densities, which in turn bias

M. Cencelj, J. Dydak, A. Vavpetic

It is well-known that a paracompact space X is of covering dimension n if and only if any map f from X to a simplicial complex K can be pushed into its n-skeleton. We use the same idea to define dimension in the coarse category. It turns out the analog of maps f from X to K is related to asymptotically Lipschitz maps, the analog of paracompact spaces are spa

Adrian Dumitrescu, Csaba D. Tóth

We revisit several maximization problems for geometric networks design under the non-crossing constraint, first studied by Alon, Rajagopalan and Suri (ACM Symposium on Computational Geometry, 1993). Given a set of $n$ points in the plane in general position (no three points collinear), compute a longest non-crossing configuration composed of straight line se

Ryan Barnett, Edward Chen, Gil Refael

In this work we consider vortex lattices in rotating Bose-Einstein Condensates composed of two species of bosons having different masses. Previously [1] it was claimed that the vortices of the two species form bound pairs and the two vortex lattices lock. Remarkably, the two condensates and the external drive all rotate at different speeds due to the dispari

I. V. Anikin, D. Yu. Ivanov, B. Pire, L. Szymanowski

We describe a consistent approach to factorization of scattering amplitudes for exclusive processes beyond the leading twist approximation. The method involves the Taylor expansion of the scattering amplitude in the momentum space around the dominant light-cone direction and thus naturally introduces an appropriate set of non-perturbative correlators which e

Yoichi Tanaka, Norio Kawakami, Akira Oguri

We study Andreev transport through double quantum dots connected in series normal and superconducting (SC) leads, using the numerical renormalization group. The ground state of this system shows a crossover between a local Cooper-pairing singlet state and a Kondo singlet state, which is caused by the competition between the Coulomb interaction and the SC pro

Romeel Davé, Kristian Finlator, Benjamin D. Oppenheimer, Mark Fardal

We study the nature of rapidly star-forming galaxies at z=2 in cosmological hydrodynamic simulations, and compare their properties to observations of sub-millimetre galaxies (SMGs). We identify simulated SMGs as the most rapidly star-forming systems that match the observed number density of SMGs. In our models, SMGs are massive galaxies sitting at the centre

Jianhui Wang, H. A. Fertig, Ganpathy Murthy

We demonstrate that in the presence of Coulomb interactions, electrons in graphene behave like a critical system, supporting power law correlations with interaction-dependent exponents. An asymptotic analysis shows that the origin of this behavior lies in particle-hole scattering, for which the Coulomb interaction induces anomalously close approaches. With i

Rieuwert J. Blok

Let Gamma be the K-shadow space of a spherical building Delta. An embedding V of Gamma is called polarized if it affords all "singular" hyperplanes of Gamma. Suppose that Delta is associated to a Chevalley group G. Then Gamma can be embedded into what we call the Weyl module for G of highest weight lambda_K. It is proved that this module is polarized

Nathaniel Johnston, David W. Kribs

We consider a family of vector and operator norms defined by the Schmidt decomposition theorem for quantum states. We use these norms to tackle two fundamental problems in quantum information theory: the classification problem for k-positive linear maps and entanglement witnesses, and the existence problem for non-positive partial transpose bound entangled s

George Savvidy

We present a brief review of the non-Abelian tensor gauge field theory and analyze its free field equations for lower rank gauge fields when the interaction coupling constant tends to zero. The free field equations are written in terms of the first order derivatives of extended field strength tensors similar to the electrodynamics and non-Abelian gauge theor

Gunter Malle, Jean Michel

We investigate the representations and the structure of Hecke algebras associated to certain finite complex reflection groups. We first describe computational methods for the construction of irreducible representations of these algebras, including a generalization of the concept of $W$-graph to the situation of complex reflection groups. We then use these te

Frank Pollmann, Erez Berg, Ari M. Turner, Masaki Oshikawa

We discuss the characterization and stability of the Haldane phase in integer spin chains on the basis of simple, physical arguments. We find that an odd-$S$ Haldane phase is a topologically non-trivial phase which is protected by any one of the following three global symmetries: (i) the dihedral group of $π$-rotations about $x,y$ and $z$ axes; (ii) time-rev

O. W. Greenberg, A. K. Mishra

We study the vacuum matrix elements of products of parafields using graphical and combinatorial methods.

Antoine Douai, Etienne Mann

We first describe a canonical mirror partner (B-model) of the small quantum orbifold cohomology of weighted projective spaces (A-model) in the framework of differential equations: we attach to the A-model (resp. B-model) a D-module on the torus and we show that these two D-modules are isomorphic. This makes the A and B-models mirror partners and yields, in t

A. Cannas da Silva, V. Guillemin, A. R. Pires

An origami manifold is a manifold equipped with a closed 2-form which is symplectic except on a hypersurface where it is like the pullback of a symplectic form by a folding map and its kernel fibrates with oriented circle fibers over a compact base. We can move back and forth between origami and symplectic manifolds using cutting (unfolding) and radial blow-

Cesar A. Valenzuela-Toledo, Yeinzon Rodriguez, David H. Lyth

We study the spectrum P_\zeta and bispectrum B_\zeta of the primordial curvature perturbation \zeta when the latter is generated by scalar and vector field perturbations. The tree-level and one-loop contributions from vector field perturbations are worked out considering the possibility that the one-loop contributions may be dominant over the tree level term

Markus Ahlers, Philipp Mertsch, Subir Sarkar

We discuss recent observations of high energy cosmic ray positrons and electrons in the context of hadronic interactions in supernova remnants, the suspected accelerators of galactic cosmic rays. Diffusive shock acceleration can harden the energy spectrum of secondary positrons relative to that of the primary protons (and electrons) and thus explain the rise

Javier von Stecher

We study the behavior of weakly bound clusters and their relation to the well-known three-body Efimov states. We adopt a model to describe universal behavior of strongly interacting bosonic systems, and we test its validity by reproducing predictions of three- and four-body universal states. Then, we extend our study to larger systems and identify a series o

Dominic D. P. Johnson, James H. Fowler

Confidence is an essential ingredient of success in a wide range of domains ranging from job performance and mental health, to sports, business, and combat. Some authors have suggested that not just confidence but overconfidence-believing you are better than you are in reality-is advantageous because it serves to increase ambition, morale, resolve, persisten

S. Wallon

We review the descriptions of hard exclusive processes based on QCD factorization.

Debaprasad Maity, Swarnendu Sarkar, B. Sathiapalan, R. Shankar

We study properties of strongly coupled CFT's with non-zero background electric charge in 1+1 dimensions by studying the dual gravity theory - which is a charged BTZ black hole. Correlators of operators dual to scalars, gauge fields and fermions are studied at both T=0 and $T\neq 0$. In the $T=0$ case we are also able to compare with analytical results b

Rachel Bean

We consider evidence for deviations from General Relativity (GR) in the growth of large scale structure, using two parameters, $γ$ and $η$, to quantify the modification. We consider the Integrated Sachs-Wolfe effect (ISW) in the WMAP Cosmic Microwave Background data, the cross-correlation between the ISW and galaxy distributions from 2MASS and SDSS surveys,

Arturo Wong, Francisco Mireles

The spin Hall and longitudinal conductivity of a 2D heavy-hole gas with {\it k}-cubic Rashba and Dresselhaus spin-orbit interaction is studied in the ac frequency domain. Using Kubo linear-response theory and a recently proposed definition for the (conserved) spin current operator suitable for spin-3/2 holes, it is shown that the spin conductivity tensor exh

Christian G. Boehmer, Francisco S. N. Lobo

Recently, Horava proposed a power counting renormalizable theory for (3+1)-dimensional quantum gravity, which reduces to Einstein gravity with a non-vanishing cosmological constant in IR, but possesses improved UV behaviors. In this work, we analyze the stability of the Einstein static universe by considering linear homogeneous perturbations in the context o

I. V. Anikin, D. Yu. Ivanov, B. Pire, L. Szymanowski

Exclusive processes in hard electroproduction is one of the best place for understanding the factorization properties of QCD. The HERA experiment recently provided precise data for rho electroproduction, including all spin density matrix elements. From QCD, it is expected that such a process should factorize between a hard (calculable) coefficient function,

Emma Y. Jin, Christian M. Reidys

In this paper we study random induced subgraphs of Cayley graphs of the symmetric group induced by an arbitrary minimal generating set of transpositions. A random induced subgraph of this Cayley graph is obtained by selecting permutations with independent probability, $λ_n$. Our main result is that for any minimal generating set of transpositions, for probab

Govind Menon, Ravi Srinivasan

We study shock statistics in the scalar conservation law $\partial_t u + \partial_x f(u)=0$, $x \in \R$, $t>0$, with a convex flux $f$ and spatially random initial data. We show that the Markov property (in $x$) is preserved for a large class of random initial data (Markov processes with downward jumps and derivatives of Lévy processes with downward jumps).

D. I. Jones

In this paper we investigate the effect of a pinned superfluid component on the gravitational wave emission of a steadily rotating deformed neutron star. We show that the superfluid pinning allows the possibility for there to be gravitational wave emission at both the stellar spin frequency $Ω$ and its first harmonic, $2Ω$. This contrasts with the convention

A. Marino, E. Iodice, R. Tantalo, L. Piovan

Systems of shells and polar rings in early-type galaxies are considered "bona fide" tracers of mass accretion and/or mergers. Their high frequency in low density environments suggests that such episodes could drive the evolution of at least a fraction of the early-type galaxy population. Their UV emission is crucial to test whether these galaxies hos

Giulio Bonelli, Alessandro Tanzini

We propose some arguments supporting an M-theory derivation of the duality recently discovered by Alday, Gaiotto and Tachikawa between two-dimensional conformal field theories and N=2 superconformal gauge theories in four dimensions. We find that A_{N-1} Toda field theory is the simplest two-dimensional conformal field theory quantizing the moduli of N M5-br

Marius Beceanu

This paper establishes new estimates for linear Schroedinger equations in R^3 with time-dependent potentials. Some of the results are new even in the time-independent case and all are shown to hold for potentials in scaling-critical, translation-invariant spaces. The proof of the time-independent results uses a novel method based on an abstract version of Wi

S. J. Gates, S. M. Kuzenko, G. Tartaglino-Mazzucchelli

The superform construction of supergravity actions, christened the "ectoplasm method," is based on the use of a closed super d-form in the case of d space-time dimensions. In known examples, such superforms are obtained by iteratively solving nontrivial cohomological problems. The latter usually makes this scheme no less laborious than the normal coo

Robert Brijder, Hendrik Jan Hoogeboom

We study the interplay between principal pivot transform (pivot) and loop complementation for graphs. This is done by generalizing loop complementation (in addition to pivot) to set systems. We show that the operations together, when restricted to single vertices, form the permutation group S_3. This leads, e.g., to a normal form for sequences of pivots and

R. C. Drumond, L. A. M. Souza, M. Terra Cunha

We investigate theoretically an open dynamics for two modes of electromagnetic field inside a microwave cavity. The dynamics is Markovian and determined by two types of reservoirs: the "natural" reservoirs due to dissipation and temperature of the cavity, and an engineered one, provided by a stream of atoms passing trough the cavity, as devised in [P

Scott B. Guthery

An elementary method for computing various prime sequences using the sequence of Farey sequences is described.

J. A. J. Matthews, R. Mesler, B. R. Becker, M. S. Gold

Cosmic ray (CR) air showers, detected via the air fluorescence technique, are reconstructed in part using functions that parameterize the longitudinal profile of each shower. The profile parameterization yields the position of shower maximum, X_max, which is sensitive to the incident CR particle type: e.g. p, C/N/O, Fe or photons. The integral of the profile

O. E. Fernandez, T. Mestdag, A. M. Bloch

In this paper we study Chaplygin's Reducibility Theorem and extend its applicability to nonholonomic systems with symmetry described by the Hamilton-Poincare-d'Alembert equations in arbitrary degrees of freedom. As special cases we extract the extension of the Theorem to nonholonomic Chaplygin systems with nonabelian symmetry groups as well as Euler-

David Monniaux

We propose a method for automatically generating abstract transformers for static analysis by abstract interpretation. The method focuses on linear constraints on programs operating on rational, real or floating-point variables and containing linear assignments and tests. In addition to loop-free code, the same method also applies for obtaining least fixed p

The MINOS Collaboration

The temperature of the upper atmosphere affects the height of primary cosmic ray interactions and the production of high-energy cosmic ray muons which can be detected deep underground. The MINOS far detector at Soudan MN, USA, has collected over 67 million cosmic ray induced muons. The underground muon rate measured over a period of five years exhibits a 4%

Jing Wang, Ren-Bao Liu, B. -F. Zhu, L. J. Sham

In coherent control, electromagnetic vacuum fluctuations usually cause coherence loss through irreversible spontaneous emission. However, since the dissipation via emission is essentially due to correlation of the fluctuations, when emission ends in a superposition of multiple final states, correlation between different pathways may build up if the "whic

Katsiaryna Krupchyk, Matti Lassas

A uniqueness result in the inverse problem for an inhomogeneous hyperbolic system on a real vector bundle over a smooth compact manifold, based on energy measurements for improperly known sources, is established.

T. Shi, Yue Yu, C. P. Sun

We study supersymmetric (SUSY) responses to a photoassociation process in a mixture of Bose molecules $b$ and Fermi atoms $f$ which turn to mutual superpartners for a set of proper parameters. We consider the molecule $b$ to be a bound state of the atom $f$ and another Fermi atom $F$ with different species. The $b$-$f$ mixture and a free $F$ atom gas are loa

Chas A. Egan, Charles H. Lineweaver

Using recent measurements of the supermassive black hole (SMBH) mass function, we find that SMBHs are the largest contributor to the entropy of the observable universe, contributing at least an order of magnitude more entropy than previously estimated. The total entropy of the observable universe is correspondingly higher, and is S_obs = 3.1+3.0-1.7x10^104 k

Jan Kretzschmar

A new measurement of the inclusive DIS ep cross section using H1 data from the year 2000 is performed and combined with published results using 1996/97 data. The new data covers the region of Q2 from 12 to 150 GeV2 at HERA with unprecedented accuracy. The structure Function F2 is extracted and studied. A QCD analysis, H1PDF 2009, is performed including the n

W. Zhao, Y. Zhang, M. L. Tong

We review the quantum Yang-Mills condensate (YMC) dark energy models. As the effective Yang-Mills Lagrangian is completely determined by the quantum field theory, there is no adjustable parameter in the model except the energy scale. In this model, the equation-of-state (EOS) of the YMC dark energy, $w_y > -1$ and $w_y < -1$, can both be naturally realized.

Jan Mrazek, Andrea Wulzer

Heavy partners of the top quark are a common prediction of many models in which a new strongly-coupled sector is responsible for the breaking of the EW symmetry. In this paper we investigate their experimental signature at the LHC, focusing on the particularly clean channel of same-sign dileptons. We show that, thank to a strong interaction with the top quar

Temo Vekua

Low temperature dependence of specific heat of one- dimensional multicomponent systems at the commensurate- incommensurate phase transition point is studied. It is found that for canonical systems, with a fixed total number of particles, low temperature specific heat linearly depends on temperature with a diverging prefactor.

G. Bormetti, V. Cazzola, G. Livan, G. Montagna

We introduce the formalism of generalized Fourier transforms in the context of risk management. We develop a general framework to efficiently compute the most popular risk measures, Value-at-Risk and Expected Shortfall (also known as Conditional Value-at-Risk). The only ingredient required by our approach is the knowledge of the characteristic function descr

Vadim R. Madgazin

The paper offers a solution to the centuries-old puzzle - why the major chords are perceived as happy and the minor chords as sad - based on the information theory of emotions. A theory and a formula of musical emotions were created. They define the sign and the amplitude of the utilitarian emotional coloration of separate major and minor chords through rela

Alina Ostafe, Igor E. Shparlinski

We use the Weil bound of multiplicative character sums together with some recent results of N. Boston and R. Jones, to show that the critical orbit of quadratic polynomials over a finite field of $q$ elements is of length $O(q^{3/4})$, improving upon the trivial bound $q$.

Hanno von Bodecker

The f-invariant is a higher version of the e-invariant that takes values in the divided congruences between modular forms; in the situation of a cartesian product of two framed manifolds, the f-invariant can actually be computed from the e-invariants of the factors. The purpose of this note is to determine the f-invariant of all such products.

Zhi Jiang

This paper is devoted to study the birational properties of the Albanese map. I generalize a theorem of Kawamata to tell when the Albanese map is surjective and when it is an algebraic fiber space.

Javier Blasco-Herrera, Kambiz Fathi, John Beckman, Leonel Gutiérrez

We analyse the internal dynamics of star-forming HII regions and their efficiency in interacting with the ISM. We use GHaFaS (Fabry-Perot) data of the nearby spiral galaxy M83 to perform multiple-Gaussian fitting to the integrated Halpha emission line for 136 HII regions, advanced instrumental response subtraction and to study the Luminosity-velocity dispers

P. Kaer, T. R. Nielsen, P. Lodahl, A. -P. Jauho

We investigate the influence of electron-phonon interactions on the dynamical properties of a quantum-dot-cavity QED system. We show that non-Markovian effects in the phonon reservoir lead to strong changes in the dynamics, arising from photon-assisted dephasing processes, not present in Markovian treatments. A pronounced consequence is the emergence of a ph

M. A. Perez-Torres, C. Romero-Canizales, A. Alberdi, A. Polatidis

Context. The central kiloparsec of many local Luminous Infra-red Galaxies are known to host intense bursts of massive star formation, leading to numerous explosions of core-collapse supernovae (CCSNe). However, the dust-enshrouded regions where those supernovae explode hamper their detection at optical and near-infrared wavelengths. Aims. We investigate the

Sergiu I. Vacaru

We prove that the Einstein equations can be solved in a very general form for arbitrary spacetime dimensions and various types of vacuum and non-vacuum cases following a geometric method of anholonomic frame deformations for constructing exact solutions in gravity. The main idea of this method is to introduce on (pseudo) Riemannian manifolds an alternative (

G. A. Mamon, E. Diaz-Gimenez

The nature of compact groups (CGs) of galaxies, apparently so dense that the galaxies often overlap, is still a subject of debate: Are CGs roughly as dense in 3D as they appear in projection? Or are they caused by chance alignments of galaxies along the line-of-sight, within larger virialized groups or even longer filamentary structures? The nature of CGs is

O. Boada, A. Celi, J. I. Latorre

It is shown that a simple modification of the geometry in which Raman lasers are applied to a cold gas in an optical lattice results in transforming the emerging effective electromagnetic field into a pure gauge. This contrived gauge-away effect can be observed experimentally by measuring the Mott-Insulator to Superfluid critical point. The underlying mechan