November 2007 arXiv papers — page 28
Showing 2,701–2,800 of 5,016 papers
Alexander Zaitsev
There is a close interrelation between Searching for Extraterrestrial Intelligence (SETI) and Messaging to Extraterrestrial Intelligence (METI). For example, the answers to the questions "Where to search" and "Where to send" are equivalent, in that both require an identical selection from the same target star lists. Similar considerations lea
Slavko Bogdanov, Jonathan E. Grindlay
In recent years, X-ray observations with Chandra and XMM-Newton have significantly increased our understanding of rotation-powered (radio) millisecond pulsars (MSPs). Deep Chandra studies of several globular clusters have detected X-ray counterparts to a host of MSPs, including 19 in 47 Tuc alone. These surveys have revealed that most MSPs exhibit thermal em
Guanghan Li, Isabel Salavessa
In this paper, we consider the mean curvature flow of convex hypersurfaces in Euclidean spaces with a general forcing term. We show that the flow may shrink to a point in finite time if the forcing term is small, or exist for all times and expand to infinity if the forcing term is large enough. The flow can also converge to a round sphere for some special fo
O. Stahl, S. Casassus, T. L. Wilson
The 12C/13C isotope ratio in the interstellar medium (ISM), and its evolution with time, is an important tracer of stellar yields. Spatial variations of this ratio can be used to study mixing in the ISM. We want to determine this ratio and its spatial variations in the local ISM from CH+ absorption lines in the optical towards early-type stars. The aim is to
Gajendra Pandey, David L. Lambert, N. Kameswara Rao
Neutral fluorine (F I) lines are identified in the optical spectra of several R Coronae Borealis stars (RCBs) at maximum light. These lines provide the first measurement of the fluorine abundance in these stars. Fluorine is enriched in some RCBs by factors of 800 to 8000 relative to its likely initial abundance. The overabundances of fluorine are evidence fo
R. G. Nazmitdinov, J. Kvasil, A. Tsvetkov
A shape evolution of 162,164Yb in yrast states is traced using the self-consistent Skyrme Hartree-Fock calculations. We found that nonaxial octupole deformations (in particular, Y_{31} term) become favorable at large rotational frequencies (> 0.4 MeV) in 162Yb, while in 164Yb a nonaxial quadrupole shape is dominant at fast rotation. The cranked Nilsson model
J. Vijande, A. Valcarce, F. Fernandez
We study the $B$ meson spectroscopy allowing the mixture of conventional $P$ wave quark-antiquark states and four-quark components. A similar picture was used to describe the new $D_J$ and $D_{sJ}$ open charm mesons. The four-quark components shift the masses of some positive parity $B_{sJ}$ states below their corresponding isospin preserving two-meson thres
J. L. Lebowitz, A. Lytova, L. Pastur
Earlier two of us (J.L. and L.P.) considered a matrix model for a two-level system interacting with a $n\times n$ reservoir and assuming that the interaction is modelled by a random matrix. We presented there a formula for the reduced density matrix in the limit $n\to \infty $ as well as several its properties and asymptotic forms in various regimes. In this
S. Karaali, S. Bilir, E. Yaz, E. Hamzaoglu
We estimated 34 sets of Galactic model parameters for three intermediate latitude fields with Galactic longitudes l=60, l=90, and l=180, and we discussed their dependence on the volume. Also, we confirmed the variation of these parameters with absolute magnitude and Galactic longitude. The star samples in two fields are restricted with bright and unit absolu
Lars Diening, Peter Hästö, Svetlana Roudenko
In this article we introduce Triebel--Lizorkin spaces with variable smoothness and integrability. Our new scale covers spaces with variable exponent as well as spaces of variable smoothness that have been studied in recent years. Vector-valued maximal inequalities do not work in the generality which we pursue, and an alternate approach is thus developed. App
K. A. P. Singh, R. Erdelyi, B. N. Dwivedi
Aims. Taking account of steady flow in solar prominences, we study its effects on spatial damping of small-amplitude non-adiabatic magnetoacoustic waves in a homogeneous, isothermal, and unbounded prominence plasma. Methods. We model the typical feature of observed damped oscillatory motion in prominences, removing the adiabaticity assumption through thermal
Carey Lisse, Mark Sykes, David Trilling, Josh Emery
The overarching goal of planetary astronomy is to deduce how the present collection of objects found in our Solar System were formed from the original material present in the proto-solar nebula. As over two hundred exo-planetary systems are now known, and multitudes more are expected, the Solar System represents the closest and best system which we can study
Dan Butnariu, Gabor Kassay
In this paper we study the convergence of an iterative algorithm for finding zeros with constraints for not necessarily monotone set-valued operators in a reflexive Banach space. This algorithm, which we call the proximal-projection method is, essentially, a fixed point procedure and our convergence results are based on new generalizations of Lemma Opial. We
Joel Hass, Tahl Nowik
We present a sequence of diagrams of the unknot for which the minimum number of Reidemeister moves required to pass to the trivial diagram is quadratic with respect to the number of crossings. These bounds apply both in $S^2$ and in $\R^2$.
Samuel Mueller, A. H. Welsh
In this paper, we extend to generalized linear models (including logistic and other binary regression models, Poisson regression and gamma regression models) the robust model selection methodology developed by Mueller and Welsh (2005; JASA) for linear regression models. As in Mueller and Welsh (2005), we combine a robust penalized measure of fit to the sampl
Recrystallization of glass: homogeneous vs. heterogeneous nucleation in La(0.5)Ca(0.5)MnO3
cond-mat.str-elA. Banerjee, Kranti Kumar, P. Chaddah
We probe through magnetization and resistivity measurements a kinetically arrested glass-like but long-range ordered magnetic state. The transformation kinetics of the magnetic field-temperature induced broad first-order transition from ferromagnetic-metallic (FMM) to antiferromagnetic-insulating (AFI) state gets hindered at low temperature in a La(0.5)Ca(0.
Anne-Laure Fougères, John P. Nolan, Holger Rootzén
This paper unifies and extends results on a class of multivariate Extreme Value (EV) models studied by Hougaard, Crowder, and Tawn. In these models both unconditional and conditional distributions are EV, and all lower-dimensional marginals and maxima belong to the class. This leads to substantial economies of understanding, analysis and prediction. One inte
Alessandro Morbidelli, Aurelien Crida, Frederic Masset, Richard P. Nelson
A well-known bottleneck for the core-accretion model of giant-planet formation is the loss of the cores into the star by Type-I migration, due to the tidal interactions with the gas disk. It has been shown that a steep surface-density gradient in the disk, such as the one expected at the boundary between an active and a dead zone, acts as a planet trap and p
Nikodem J. Poplawski
We derive conservation laws for energy-momentum (canonical and dynamical) and angular momentum for a general Lorentz connection.
Edge-functionalized and substitutional doped graphene nanoribbons: electronic and spin properties
cond-mat.mtrl-sciF. Cervantes-Sodi, G. Csányi, S. Piscanec, A. C. Ferrari
Graphene nanoribbons are the counterpart of carbon nanotubes in graphene-based nanoelectronics. We investigate the electronic properties of chemically modified ribbons by means of density functional theory. We observe that chemical modifications of zigzag ribbons can break the spin degeneracy. This promotes the onset of a semiconducting-metal transition, or
Sergey V. Golovin
It is noticed, that partially invariant solution (PIS) of differential equations in many cases can be represented as an invariant reduction of some PIS of the higher rank. This introduce a hierarchic structure in the set of all PISs of a given system of differential equations. By using this structure one can significantly decrease an amount of calculations r
Stefan C. Keller, Simon Murphy, Sayuri Prior, Gary DaCosta
We present a search for RR Lyrae variable stars from archival observations of the Southern Edgeworth-Kuiper Belt Object survey. The survey covers 1675 square degrees along the ecliptic to a mean depth of V=19.5, i.e. a heliocentric distance of ~50kpc for RR Lyrae stars. The survey reveals 2016 RR Lyrae candidates. Follow-up photometric monitoring of a subset
Magnetic Field versus Temperature Phase Diagram of the Spin-1/2 Alternating Chain Compound F5PNN
cond-mat.str-elYasuo Yoshida, Tatsuya Kawae, Yuko Hosokoshi, Katsuya Inoue
We have measured the specific heat of the S = 1/2 alternating Heisenberg antiferromagnetic chain compound pentafluorophenyl nitronyl nitroxide in magnetic fields using a single crystal and powder. A sharp peak due to field-induced magnetic ordering (FIMO) is observed in both samples. The H-T phase boundary of the FIMO of the single crystal is symmetric with
Bo-Qiang Ma
It is shown that the observed small value of the integrated spin structure function for protons could be naturally understood within the naive quark model by considering the effect from Melosh rotation. The key to this problem lies in the fact that the deep inelastic process probes the light-cone quarks rather than the instant-form quarks, and that the spin
Titu Andreescu, Zoran Sunic
A solution function for convex transferable utility games encourages the grand coalition if no player prefers (in a precise sense defined in the text) any coalition to the grand coalition. We show that the Shapley value encourages the grand coalition in all convex games and the tau-value encourages the grand coalitions in convex games up to three (but not mo
The Structures of Distant Galaxies I: Galaxy Structures and the Merger Rate to z~3 in the Hubble Ultra-Deep Field
astro-phChristopher J. Conselice, Sheena Rajgor, Robert Myers
This paper begins a series in which we examine the structures of distant galaxies to directly determine the history of their formation modes. We start this series by examining the structures of z_F850LP < 27 galaxies in the Hubble Ultra-Deep field, the deepest high-resolution optical image taken to date. We investigate a few basic features of galaxy structur
Igor V. Mel'nikov, Anton Knigavko, J. Stewart Aitchison, Clark A. Merchant
We demonstrate interesting and previously unforeseen properties of a pair of gap solitons in a resonant photonic crystal which are predicted and explained in a physically transparent form using both analytical and numerical methods. The most important result is the fact that an oscillating gap soliton created by the presence of a localized population inversi
A shape of charged particle lateral distribution in individual EAS events with energy above 10^19 eV arriving from different celestial regions
astro-phA. V. Sabourov, M. I. Pravdin, S. P. Knurenko
A shape of lateral distribution for charged particles in events with energy above 10^19eV is considered. Two methods were used for individual LDF parametrization. In the first approach, the index of power was determined for generalized Greisen-Linsley approximation. In second, mean square radius of the shower was determined for approximation proposed by Lagu
Hiroki Takesue, Yasuhiro Tokura, Hiroshi Fukuda, Tai Tsuchizawa
We report the first entanglement generation experiment that utilizes a silicon waveguide. Using spontaneous four-wave mixing in a 1.09-cm-long silicon wire waveguide, we generated 1.5-um, high-purity time-bin entangled photons without temperature control, and observed a two-photon interference fringe with >73% visibility.
Spectropolarimetric observations of Herbig Ae/Be Stars I: HiVIS spectropolarimetric calibration and reduction techniques
astro-phD. M. Harrington, J. R. Kuhn
Using the HiVIS spectropolarimeter built for the Haleakala 3.7m AEOS telescope in Hawaii, we are collecting a large number of high precision spectropolarimetrc observations of stars. In order to precisely measure very small polarization changes, we have performed a number of polarization calibration techniques on the AEOS telescope and HiVIS spectrograph. We
D. Fargion, M. Gaug, P. Oliva
Magic Telescope may observe and reveal at horizons lights from air-shower Cherenkov reflections. The ground, the sea, the cloudy sky (below the mountain) may reflect PeVs-EeV UHECR Cherenkov lights observable by MAGIC telescopes. Even rarest UHE neutrino skimming the atmosphere or skimming the Earth may induce upward-horizontal airshowers: a new Neutrino Ast
Yoshiaki Koma, Miho Koma, Hartmut Wittig
We investigate the relativistic corrections to the static potential, i.e. the O(1/m) potential and the O(1/m^2) velocity-dependent potentials, in SU(3) lattice gauge theory. They are important ingredients of potential nonrelativistic QCD for heavy quarkonium. Utilizing the multi-level algorithm, we obtain remarkably clean signals of these potentials up to r=
Axel de la Macorra, Leonardo Patino
We consider the spectrum of mesons for the gauge theory dual to a supergravity configuration of intersecting D3/D7 branes, and use the expression for the Lagrangian of the scalar mesons to compute explicitly the Lagrangian for the lightest states in the infrared limit. Assuming that the matter content of this gauge theory is part of a hidden sector, which in
Zhedanov's Algebra AW(3) and the Double Affine Hecke Algebra in the Rank One Case. II. The Spherical Subalgebra
math.QATom H. Koornwinder
This paper builds on the previous paper arXiv:math/0612730 by the author, where a relationship between Zhedanov's algebra AW(3) and the double affine Hecke algebra (DAHA) corresponding to the Askey-Wilson polynomials was established. It is shown here that the spherical subalgebra of this DAHA is isomorphic to AW(3) with an additional relation that the Casimi
Wen Zhao
We study the statefinder parameters in the Yang-Mills condensate dark energy models, and find that the evolving trajectories of these models are different from those of other dark energy models. We also define two eigenfunctions of the Yang-Mills condensate dark energy models. The values of these eigenfunctions are quite close to zero if the equation-of-stat
Sergey A. Cherkis, Brian Durcan
We present explicit BPS field configurations representing one nonabelian monopole with one minimal weight 't Hooft operator insertion. We explore the SO(3) and SU(2) gauge groups. In the case of SU(2) gauge group the minimal 't Hooft operator can be completely screened by the monopole. If the gauge group is SO(3), however, such screening is impossibl
Entanglement Entropy, decoherence, and quantum phase transition of a dissipative two-level system
cond-mat.mes-hallKaryn Le Hur
The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the spin-boson model, which describes a qubit (two-level system) interacting with a collection of harmonic oscillators that mo
Peter P. Orth, Ivan Stanic, Karyn Le Hur
Using cold bosonic atoms with two (hyperfine) ground states, we introduce a spin-boson mixture which allows to implement the quantum Ising model in a tunable dissipative environment. The first specie lies in a deep optical lattice with tightly confining wells and forms a spin array; spin-up/down corresponds to occupation by one/no atom at each site. The seco
Matilde Martínez, Shigenori Matsumoto, Alberto Verjovsky
We study the dynamics of the geodesic and horocycle flows of the unit tangent bundle $(\hat M, T^1\mathcal{F})$ of a compact minimal lamination $(M,\mathcal F)$ by negatively curved surfaces. We give conditions under which the action of the affine group generated by the joint action of these flows is minimal, and examples where this action is not minimal. In
Priyamvada Natarajan, Darren Croton, Gianfranco Bertone
Galaxy formation requires a process that continually heats gas and quenches star formation in order to reproduce the observed shape of the luminosity function of bright galaxies. To accomplish this, current models invoke heating from supernovae, and energy injection from active galactic nuclei. However, observations of radio-loud active galactic nuclei sugge
Sean Fleming, Andre H. Hoang, Sonny Mantry, Iain W. Stewart
We consider top-quarks produced at large energy in e+e- collisions, and address the question of what top-mass can be measured from reconstruction. The production process is characterized by well separated scales: the center-of-mass energy, Q, the top mass, m, the top decay width, Gamma_t, and also LambdaQCD; scales which can be disentangled with effective th
Dmitry V. Belyaev, Peter van Nieuwenhuizen
Using the simple setting of 3D N=1 supergravity, we show how the tensor calculus of supergravity can be extended to manifolds with boundary. We present an extension of the standard F-density formula which yields supersymmetric bulk-plus-boundary actions. To construct additional separately supersymmetric boundary actions, we decompose bulk supergravity and bu
Anton Bovier, Anton Klimovsky
This paper has been temporarily withdrawn for revision by the authors.
Brian M. Andersen, P. J. Hirschfeld
The prediction and observation of low-temperature universal thermal conductivity in cuprates has served as a keystone of theoretical approaches to the superconducting state, but recent measurements on underdoped samples show strong violations of this apparently fundamental property of d-wave nodal quasiparticles. Here, we show that the breakdown of universal
Optical/Infrared Observations of the Anomalous X-ray Pulsar 1E 1048.1-5937 During Its 2007 X-Ray Flare
astro-phZ. Wang, C. Bassa, V. M. Kaspi, J. B. Bryant
We report on optical and infrared observations of the anomalous X-ray pulsar (AXP) 1E 1048.1-5937, made during its ongoing X-ray flare which started in 2007 March. We detected the source in the optical I and near-infrared Ks bands in two ground-based observations and obtained deep flux upper limits from four observations, including one with the Spitzer Space
Disentangling CP phases in nearly degenerate resonances: neutralino production via Higgs at a muon collider
hep-phHerbi K. Dreiner, Olaf Kittel, Federico von der Pahlen
In the CP-violating Minimal Supersymmetric Standard Model, we study the pair production of neutralinos at center-of-mass energies around the heavy neutral Higgs boson resonances. For longitudinally polarized muon beams, we analyze CP asymmetries which are sensitive to the interference of the two heavy neutral Higgs bosons. Due to radiatively induced scalar-p
Nicolas Douguet, Juan Blandon, Viatcheslav Kokoouline
We discuss collision of three identical particles and derive scattering selection rules from initial to final states of the particles. We use either laboratory-frame, hyperspherical, or Jacobian coordinates depending on which one is best suited to describe three different configurations of the particles: (1) three free particles, (2) a quasi-bound trimer, or
Mohamed Assad Abdel-Raouf
Recent productions of large numbers of cold antiprotons as well as the formation of antihydrogens at CERN and Fermilab have raised basic questions about possible coexistence of matter and antimatter in nature. In the present work, previous mathematical considerations are revisited which support the possible coexistence of Antihydrogen with Hydrogen, Deuteriu
Xiang-Yu Wang, Soebur Razzaque, Peter Meszaros
The chemical composition of the ultra-high-energy (UHE) cosmic rays serves as an important clue for their origin. Recent measurements of the elongation rates by the Pierre Auger Observatory hint at the possible presence of heavy or intermediate mass nuclei in the UHE cosmic rays. Gamma-ray bursts (GRBs) and hypernovae have been suggested as possible sources
R. Aldrovandi, J. G. Pereira
The Poincare' group generalizes the Galilei group for high-velocity kinematics. The de Sitter group is assumed to go one step further, generalizing Poincare' as the group governing high-energy kinematics. In other words, ordinary special relativity is here replaced by de Sitter relativity. In this theory, the cosmological constant is no longer a free
High-excitation OH and H_2O lines in Markarian 231: the molecular signatures of compact far-infrared continuum sources
astro-phEduardo González-Alfonso, Howard A. Smith, Matthew L. N. Ashby, Jacqueline Fischer
The ISO/LWS far-infrared spectrum of the ultraluminous galaxy Mkn 231 shows OH and H_2O lines in absorption from energy levels up to 300 K above the ground state, and emission in the [O I] 63 micron and [C II] 158 micron lines. Our analysis shows that OH and H_2O are radiatively pumped by the far-infrared continuum emission of the galaxy. The absorptions in
A. DeBenedictis
The possible existence of black holes has fascinated scientists at least since Michell and Laplace's proposal that a gravitating object could exist from which light could not escape. In the 20th century, in light of the general theory of relativity, it became apparent that, were such objects to exist, their structure would be far richer than originally imagi
Amir H. Fariborz, Renata Jora, Joseph Schechter
A brief discussion of the recent interest in light scalar mesons motivates the study of a generalized linear sigma model. In an SU(3) flavor invariant version of the model there is a prediction that the the lighter scalars have sizeable "four quark" content. It is further predicted that one of the singlet scalars should be exceptionally light. Due to
Jun Takahashi
Strange particle production is an important experimental observable that allows the study of the strongly interacting matter created in relativistic heavy-ion collisions. The STAR experiment at RHIC has a unique capability of measuring identified strange particles over a wide range of acceptance providing a rich set of data to perform a systematic study. In
J. E. Nelson, R. F. Picken
In the context of quantum gravity for spacetimes of dimension 2+1, we describe progress in the construction of a quantum Goldman bracket for intersecting loops on surfaces. Using piecewise linear paths in R^2 (representing loops on the spatial manifold, i.e. the torus) and a quantum connection with noncommuting components, we review how holonomies and Wilson
Spectral Energy Distributions of High Mass Proto Stellar Objects - Evidence for High Accretion Rates
astro-phF. M. Fazal, T. K. Sridharan, K. Qiu, T. P. Robitaille
The spectral energy distributions (SEDs), spanning the mid-infrared to millimeter wavelengths, of a sample of 13 high-mass protostellar objects (HMPOs) were studied using a large archive of 2-D axisymmetric radiative transfer models. Measurements from the Spitzer GLIMPSE and MIPSGAL surveys and the MSX survey were used in addition to our own surveys at milli
M. Blasone, F. Dell'Anno, S. De Siena, M. Di Mauro
In the physics of flavor mixing, the flavor states are given by superpositions of mass eigenstates. By using the occupation number to define a multiqubit space, the flavor states can be interpreted as multipartite mode-entangled states. By exploiting a suitable global measure of entanglement, based on the entropies related to all possible bipartitions of the
The VLT-FLAMES survey of massive stars: rotation and nitrogen enrichment as the key to understanding massive star evolution
astro-phI. Hunter, I. Brott, D. J. Lennon, N. Langer
Rotation has become an important element in evolutionary models of massive stars, specifically via the prediction of rotational mixing. Here, we study a sample of stars, including rapid rotators, to constrain such models and use nitrogen enrichments as a probe of the mixing process. Chemical compositions (C, N, O, Mg and Si) have been estimated for 135 early
Yi-Fu Cai, Taotao Qiu, Robert Brandenberger, Yun-Song Piao
A Quintom universe with an equation-of-state crossing the cosmological constant boundary can provide a bouncing solution dubbed the Quintom Bounce and thus resolve the Big Bang singularity. In this paper, we investigate the cosmological perturbations of the Quintom Bounce both analytically and numerically. We find that the fluctuations in the dominant mode i
Felix Fehr
The ANTARES neutrino telescope is currently being constructed in the Mediterranean Sea. The complete detector will consist of 12 strings, supplemented by an additional instrumentation line. Nine strings are at present deployed of which five are already connected to the shore and operating. Each string is equipped with 75 Optical Modules (OMs) housing the pho
Anne-Sophie Kaloghiros
This paper studies the defect of terminal Gorenstein Fano 3 folds. I determine a bound on the defect of terminal Gorenstein Fano 3-folds of Picard rank 1 that do not contain a plane. I give a general bound for quartic 3-folds and indicate how to study the defect of terminal Gorenstein Fano 3-folds with Picard rank 1 that contain a plane.
J. E. S. Costa, S. O. Kepler, D. E. Winget, M. S. O'Brien
PG 1159-035, a pre-white dwarf with T_eff=140,000 K, is the prototype of both two classes: the PG1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. In this work, we used all ava
Mattia Cafasso
We propose a method for computing any Gelfand-Dickey tau function living in Segal-Wilson Grassmannian as the asymptotics of block Toeplitz determinant associated to a certain class of symbols. Also truncated block Toeplitz determinants associated to the same symbols are shown to be tau function for rational reductions of KP. Connection with Riemann-Hilbert p
Guest Charge and Potential Fluctuations in Two-Dimensional Classical Coulomb Systems
cond-mat.stat-mechBernard Jancovici, Ladislav Šamaj
A known generalization of the Stillinger-Lovett sum rule for a guest charge immersed in a two-dimensional one-component plasma (the second moment of the screening cloud around this guest charge) is more simply retrieved, just by using the BGY hierarchy for a mixture of several species; the zeroth moment of the excess density around a guest charge immersed in
Kerry M. Soileau
If A is infinite and well-ordered, then |2^A|<=|Part(A)|<=|A^A|.
M. Z. Garaev
Let $q$ be a large prime number, $a$ be any integer, $ε$ be a fixed small positive quantity. Friedlander and Shparlinksi \cite{FSh} have shown that there exists a positive integer $n\ll q^{5/2+ε}$ such that $ϕ(n)$ falls into the residue class $a \pmod q.$ Here, $ϕ(n)$ denotes Euler's function. In the present paper we improve this bound to $n\ll q^{2+ε}.$
Alexander Chervov, Gregorio Falqui
We study special class of matrices with noncommutative entries and demonstrate their various applications in integrable systems theory. They appeared in Yu. Manin's works in 87-92 as linear homomorphisms between polynomial rings; more explicitly they read: 1) elements in the same column commute; 2) commutators of the cross terms are equal: $[M_{ij}, M_{k
Evolution of the Fermi Surface across a Magnetic Order-Disorder Transition in the Two-Dimensional Kondo Lattice Model: A Dynamical Cluster Approach
cond-mat.str-elL. C. Martin, F. F. Assaad
We use the dynamical cluster approximation, with a quantum Monte Carlo cluster solver on clusters of up to 16 orbitals, to investigate the evolution of the Fermi surface across the magnetic order-disorder transition in the two-dimensional doped Kondo lattice model. In the paramagnetic phase we observe the generic hybridized heavy fermion band structure with
Anne M. Green, Ben Morgan
We study the consequences of limited recoil sense reconstruction on the number of events required to reject isotropy and detect a WIMP signal using a directional detector. For a constant probability of determining the sense correctly, 3-d read-out and zero background, we find that as the probability is decreased from 1.0 to 0.75 the number of events required
Didier Poilblanc
I introduce a doped two-dimensional quantum dimer model describing a doped Mott insulator and retaining the original Fermi statistics of the electrons. This model shows a rich phase diagram including a d-wave hole-pair unconventional superconductor at small enough doping and a bosonic superfluid at large doping. The hole kinetic energy is shown to favor bind
C. B. Korn, U. S. Schwarz
Motivated by rolling adhesion of white blood cells in the vasculature, we study how cells move in linear shear flow above a wall to which they can adhere via specific receptor-ligand bonds. Our computer simulations are based on a Langevin equation accounting for hydrodynamic interactions, thermal fluctuations and adhesive interactions. In contrast to earlier
N. Brouzakis, N. Tetradis, C. Wetterich
Neutrinos interacting with the quintessence field can trigger the accelerated expansion of the Universe. In such models with a growing neutrino mass the homogeneous cosmological solution is often unstable to perturbations. We present static, spherically symmetric solutions of the Einstein equations in the same models. They describe astophysical objects compo
A. V. Tsiganov
Locally any completely integrable system is maximally superintegrable system such as we have the necessary number of the action-angle variables. The main problem is the construction of the single-valued additional integrals of motion on the whole phase space by using these multi-valued action-angle variables. Some constructions of the additional integrals of
Graham Smith
This submission has been withdrawn by the author and superseded by arXiv:0804.0744.
B. Gendre, A. Galli, M. Boer
We investigate the clustering of afterglow light curves observed at X-ray and optical wavelengths. We have constructed a sample of 61 bursts with known dis tance and X-ray afterglow. This sample includes bursts observed by BeppoSAX, XMM-Newton, Chandra, and SWIFT. We correct the light curves for cosmological ef fects and compare the observed X-ray fluxes one
Gravitational dynamics of an infinite shuffled lattice: early time evolution and universality of non-linear correlations
cond-mat.stat-mechThierry Baertschiger, Michael Joyce, Francesco Sylos Labini, Bruno Marcos
In two recent articles a detailed study has been presented of the out of equilibrium dynamics of an infinite system of self-gravitating points initially located on a randomly perturbed lattice. In this article we extend the treatment of the early time phase during which strong non-linear correlations first develop, prior to the onset of ``self-similar'&#
Olaf Post
The aim of the present paper is to introduce a first order approach to the abstract concept of boundary triples for Laplace operators. Our main application is the Laplace operator on a manifold with boundary; a case in which the ordinary concept of boundary triples does not apply directly. In our first order approach, we show that we can use the usual bounda
Jan Christian Rohde
We construct families of Calabi-Yau manifolds with dense set of complex multiplication fibers in an arbitrary dimension. We will also give explicite examples of complex multiplication fibers. For this construction we use families of curves with dense set of complex multiplication fibers. In addition, we give examples of such families for each genus less or e
Thermodynamical description of the interaction between holographic dark energy and dark matter
hep-thBin Wang, Chi-Yong Lin, Diego Pavon, Elcio Abdalla
We present a thermodynamical description of the interaction between holographic dark energy and dark matter. If holographic dark energy and dark matter evolve separately, each of them remains in thermodynamic equilibrium. A small interaction between them may be viewed as a stable thermal fluctuation that brings a logarithmic correction to the equilibrium ent
U. Mitra-Kraev, A. G. Kosovichev, T. Sekii
Aims. With the Solar Optical Telescope on Hinode, we investigate the basic properties of high-degree solar oscillations observed at two levels in the solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H line (chromospheric emission). Methods. We analyzed the data by calculating the individual power spectra as well as the cross-spect
Jacob Bock Axelsen, Sebastian Bernhardsson, Kim Sneppen
The relationship between the regulatory design and the functionality of molecular networks is a key issue in biology. Modules and motifs have been associated to various cellular processes, thereby providing anecdotal evidence for performance based localization on molecular networks. To quantify structure-function relationship we investigate similarities of p
C. A. S. Young, R. Zegers
To speak about identical particles - bosons or fermions - in quantum field theories with kappa-deformed Poincare symmetry, one must have a kappa-covariant notion of particle exchange. This means constructing intertwiners of the relevant representations of kappa-Poincare. We show, in the simple case of spinless particles, that intertwiners exist, and, support
J. Heinrichs
We study analytically the effect of a correlated random potential on the persistent current in a one-dimensional ring threaded by a magnetic flux $ϕ$, using an Anderson tight-binding model. In our model, the system of $N=2M$ atomic sites of the ring is assumed to be partitioned into $M$ pairs of identical nearest-neighbour sites (dimers). The site energies f
Masafumi Seriu, Chun-Hsien Wu
The quantum Brownian motion of a charged particle in the electromagnetic vacuum fluctuations is investigated near a perfectly reflecting flat boundary, taking into account the smooth switching process in the measurement. Constructing a smooth switching function by gluing together a plateau and the Lorentzian switching tails, it is shown that the switching ta
Jan E. Aman, Narit Pidokrajt, John Ward
In this talk we present the latest results from our ongoing project on geometro-thermodynamics (also known as information geometry of thermodynamics or Ruppeiner geometry) of dilaton BHs in 4D in both Einstein and string frames and a dyonic dilaton BH and at the end we report very briefly results from this approach to the 2D dilaton BHs.
Bin Chen, Chang-Yong Liu, Jun-Bao Wu
The operator product expansion (OPE) of the Wilson surface operators in six-dimensional (2, 0) superconformal field theory is studied from AdS/CFT correspondence in this paper. We compute the OPE coefficients of the chiral primary operators using the M5-brane description for spherical Wilson surface operators in higher dimensional representations. We use the
Markus Diehl, Wolfgang Kugler
We study the evolution behavior of generalized parton distributions at small longitudinal momentum fraction. Particular attention is paid to the ratio of a generalized parton distribution and its forward limit, to the mixing between quarks and gluons, and to the dependence on the squared momentum transfer t.
Y. Miyazaki
We search for lepton-flavor-violating tau decays into three leptons (electron or muon) using 535 fb-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. No evidence for these decays is observed, and we set 90% confidence level upper limits on the branching fractions of (2.0-4.1)x10^-8. These results improve upon our previo
Paul D. Mitchener
In this article we prove that the $KH$-asembly map, as defined by Bartels and L{ü}ck, can be described in terms of the algebraic $KK$-theory of Cortinas and Thom. The $KK$-theory description of the $KH$-assembly map is similar to that of the Baum-Connes assembly map. In very elementary cases, methods used to prove the Baum-Connes conjecture also apply to the
Yohann Duguet, Ashley P. Willis, Rich R. Kerswell
The laminar-turbulent boundary S is the set separating initial conditions which relaminarise uneventfully from those which become turbulent. Phase space trajectories on this hypersurface in cylindrical pipe flow look to be chaotic and show recurring evidence of coherent structures. A general numerical technique is developed for recognising approaches to thes
Carsten Gundlach
The numerical relativity session at GR18 was dominated by physics results on binary black hole mergers. Several groups can now simulate these from a time when the post-Newtonian equations of motion are still applicable, through several orbits and the merger to the ringdown phase, obtaining plausible gravitational waves at infinity, and showing some evidence
Possible evidence for an inverted temperature-density relation in the intergalactic medium from the flux distribution of the Lyman-alpha forest
astro-phJ. S. Bolton, M. Viel, T. -S. Kim, M. G. Haehnelt
We compare the improved measurement of the Lya forest flux probability distribution at 1.7<z<3.2 presented by Kim et al. (2007) to a large set of hydrodynamical simulations of the Lya forest with different cosmological parameters and thermal histories. The simulations are in good agreement with the observational data if the temperature-density relation for t
Frithjof B. Anders, David E. Logan, Martin R. Galpin, Gleb Finkelstein
We present numerical renormalization group calculations for the zero-bias conductance of quantum dots made from semiconducting carbon nanotubes. These explain and reproduce the thermal evolution of the conductance for different groups of orbitals, as the dot-lead tunnel coupling is varied and the system evolves from correlated Kondo behavior to more weakly c
Rainer Buckdahn, Boualem Djehiche, Juan Li, Shige Peng
Mathematical mean-field approaches play an important role in different fields of Physics and Chemistry, but have found in recent works also their application in Economics, Finance and Game Theory. The objective of our paper is to investigate a special mean-field problem in a purely stochastic approach: for the solution $(Y,Z)$ of a mean-field backward stocha
I. Guillamon, H. Suderow, F. Guinea, S. Vieira
We present scanning tunneling microscopy and spectroscopy measurements at 100mK in the superconducting material 2H-NbSe2 that show well defined features in the superconducting density of states changing in a pattern closely following atomic periodicity. Our experiment demonstrates that the intrinsic superconducting density of states can show atomic size modu
V. V. Khruschov
A generalized algebra of quantum observables, depending on extra dimensional constants, is considered. Some limiting forms of the algebra are investigated and their possible applications to the descriptions of interactions of fundamental particles are proposed. A relation between current and constituent quark masses is found using a modified quark equation o
Bodo Manthey
We present approximation algorithms for almost all variants of the multi-criteria traveling salesman problem (TSP). First, we devise randomized approximation algorithms for multi-criteria maximum traveling salesman problems (Max-TSP). For multi-criteria Max-STSP, where the edge weights have to be symmetric, we devise an algorithm with an approximation ratio
Paul D. Mitchener
In this paper we refine a version of bivariant $K$-theory developed by Cuntz to define symmetric spectra representing the $KK$-theory of $C^\ast$-categories and discrete groupoid $C^\ast$-algebras. In both cases, the Kasparov product can be expressed as a smash product of spectra.
Jean-Christophe Aval
Lascoux and Schützenberger introduced a notion of key associated to any Young tableau. More recently Lascoux defined the key of an alternating sign matrix by recursively removing all -1's in such matrices. But alternating sign matrices are in bijection with monotone triangles, which form a subclass of Young tableaux. We show that in this case these two n
J. Carr, D. Dornic, F. Jouvenot, U. F. Katz
The observation of high-energy neutrinos from astrophysical sources would substantially improve our knowledge and understanding of the non-thermal processes in these sources, and would in particular pinpoint the accelerators of cosmic rays. The sensitivity of different design options for a future cubic-kilometre scale neutrino telescope in the Mediterranean