November 2007 arXiv papers — page 10
Showing 901–1,000 of 5,016 papers
A. K. Ciftci, R. Ciftci, S. Sultansoy
Possible single productions of the fourth standard model generation neutrino via anomalous interactions at the future ep colliders are studied. Signatures of such anomalous processes and backgrounds are discussed in detail. Discovery limits for neutrino mass and achievable values of anomalous coupling strength are determined.
Jeffrey Burdges
Jaligot's Lemma states that the Fitting subgroups of distinct Borel subgroups do not intersect in a tame minimal simple groups of finite Morley. Such a strong result appears hopeless without tameness. Here we use the 0-unipotence theory to build a toolkit for the analysis of nonabelian intersections of Borel subgroups. As a demonstration, we show that an
M. Kindermann
We show that exchange interactions in two-dimensional electron gases out of equilibrium can generate a fictitious vector potential with intriguing signatures in interference and Hall measurements. Detailed predictions are made for graphene, where the effect is enhanced by pseudospin exchange.
Marta Asaeda, Seidai Yasuda
We show that any graph, in the sequence given by Haagerup in 1991 as that of candidates of principal graphs of subfactors, is not realized as a principal graph except for the smallest two. This settles the remaining case of a previous work of the first author.
A study of the breakdown of the quasi-static approximation at high densities and its effect on the helium-like K ALPHA complex of nickel, iron, and calcium
physics.atom-phJustin Oelgoetz, Christopher J. Fontes, Hong Lin Zhang, Anil K. Pradhan
The General Spectral Modeling (GSM) code employs the quasi-static approximation, a standard, low-density methodology that assumes the ionization balance is separable from a determination of the excited-state populations that give rise to the spectra. GSM also allows for some states to be treated only as contributions to effective rates. While these two appro
V. G. Gorbounov, A. P. Isaev, O. V. Ogievetsky
Quantum Lie algebras (an important class of quadratic algebras arising in the Woronowicz calculus on quantum groups) are generalizations of Lie (super) algebras. Many notions from the theory of Lie (super)algebras admit ``quantum'' generalizations. In particular, there is a BRST operator Q (Q^2=0) which generates the differential in the Woronowicz th
Matthias Beck, Christian Haase, Steven V. Sam
We examine domino tilings of rectangular boards, which are in natural bijection with perfect matchings of grid graphs. This leads to the study of their associated perfect matching polytopes, and we present some of their properties, in particular, when these polytopes are Gorenstein. We also introduce the notion of domino stackings and present some results an
Todd A. Brun, Lajos Diosi, Walter T. Strunz
Current quantum computer technology is sufficient to realize weak measurements and the corresponding concept of weak values. We demonstrate how the weak value anomaly can be tested, along with consistency and simultaneity of weak values, using only discrete degrees of freedom. All you need is a quantum computer with two--or better, three--qubits. We also giv
Apostolos Pilaftsis
Scalar condensation, the well-established Higgs phenomenon, is the standard paradigm for building up renormalizable gauge-invariant theories of massive gauge bosons. In this short note, we demonstrate the uniqueness of the Higgs vacuum state under the possible presence of fermion condensates in a renormalizable U(1) model. In the same context, we explain why
Measurement of photons via conversion pairs in Au+Au collisions at sqrt(s_NN) = 200 GeV with the PHENIX experiment at RHIC
nucl-exTorsten Dahms
Thermal photons can provide information on the temperature of the new state of matter created at RHIC. In the p_T region of 1--3 GeV/c thermal photons are expected to be the dominant direct photon source. Therefore, a possible excess compared to a pure decay photon signal due to a thermal photon contribution should be seen in the double ratio (gamma/gamma(pi
Elizeu Santos-Neto, Matei Ripeanu, Adriana Iamnitchi
Tagging communities represent a subclass of a broader class of user-generated content-sharing online communities. In such communities users introduce and tag content for later use. Although recent studies advocate and attempt to harness social knowledge in this context by exploiting collaboration among users, little research has been done to quantify the cur
Jean-Luc Thiffeault, Khalid Kamhawi
When a shallow layer of inviscid fluid flows over a substrate, the fluid particle trajectories are, to leading order in the layer thickness, geodesics on the two-dimensional curved space of the substrate. Since the two-dimensional geodesic equation is a two degree-of-freedom autonomous Hamiltonian system, it can exhibit chaos, depending on the shape of the s
Andrzej Adamczak, Mark P. faifman
The muon-catalyzed-fusion processes in D$_2$ gas for various temperatures and densities have been studied by means of Monte Carlo simulations. In particular, the role of the resonant and nonresonant $dd\mu$ formation and differences between the neutron time spectra from the ortho-D$_2$ and para-D$_2$ targets at low temperatures have been investigated.
Denis A. Leahy, Wenwu Tian
The supernova remnant (SNR) Kes 75/PSR J1846-0258 association can be regarded as certain due to the accurate location of young PSR J1846-0258 at the center of Kes 75 and the detected bright radio/X-ray synchrotron nebula surrounding the pulsar. We provide a new distance estimate to the SNR/pulsar system by analyzing the HI and $^{13}$CO maps, the HI emission
J. Tueller, R. F. Mushotzky, S. Barthelmy, J. K. Cannizzo
We present the results of the analysis of the first 9 months of data of the Swift BAT survey of AGN in the 14-195 keV band. Using archival X-ray data or follow-up Swift XRT observations, we have identified 129 (103 AGN) of 130 objects detected at |b|> 15 deg and with significance >4.8 sigma. One source remains unidentified. These same X-ray data have allowed
Marilena LoVerde, Amber Miller, Sarah Shandera, Licia Verde
The detection of primordial non-Gaussianity could provide a powerful means to test various inflationary scenarios. Although scale-invariant non-Gaussianity (often described by the $f_{NL}$ formalism) is currently best constrained by the CMB, single-field models with changing sound speed can have strongly scale-dependent non-Gaussianity. Such models could eva
Ayres Freitas, Kyoungchul Kong
We study the ILC phenomenology of (1,0) Kaluza-Klein (KK) modes along two universal extra dimensions compactified on the chiral square. We compute production cross sections of various (1,0) particles at the ILC with sqrt(s)=1 TeV, focusing on decays of KK-leptons and the KK partner of hypercharge gauge boson down to the "spinless photon", which is th
J. G. Christensen, G. Ólafsson
In this paper we summarize and give examples of a generalization of the coorbit space theory initiated in the 1980's by H.G. Feichtinger and K.H. Gröchenig. Coorbit theory has been a powerful tool in characterizing Banach spaces of distributions with the use of integrable representations of locally compact groups. Examples are a wavelet characterization
Veronika E. Hubeny, Mukund Rangamani
We present a simple derivation of the entanglement entropy for a region made up of a union of disjoint intervals in 1+1 dimensional quantum field theories using holographic techniques. This generalizes the results for 1+1 dimensional conformal field theories derived previously by exploiting the uniformization map. We further comment on the generalization of
A. Celotti, G. Ghisellini
We estimate the power of relativistic, extragalactic jets by modelling the spectral energy distribution of a large number of blazars. We adopt a simple one-zone, homogeneous, leptonic synchrotron and inverse Compton model, taking into account seed photons originating both locally in the jet and externally. The blazars under study have an often dominant high
Jason F. Rowe, Jaymie M. Matthews, Sara Seager, Eliza Miller-Ricci
Measuring the albedo of an extrasolar planet provides insights into its atmospheric composition and its global thermal properties, including heat dissipation and weather patterns. Such a measurement requires very precise photometry of a transiting system sampling fully many phases of the secondary eclipse. Spacebased optical photometry of the transiting syst
Constraints on the correlation between QSO luminosity and host halo mass from high-redshift quasar clustering
astro-phMartin White, Paul Martini, J. D. Cohn
Recent measurements of high-redshift QSO clustering from the Sloan Digital Sky Survey indicate that QSOs at z~4 have a bias b~14. We find that this extremely high clustering amplitude, combined with the corresponding space density, constrains the dispersion in the L-Mhalo relation to be less than 50% at 99% confidence for the most conservative case of a 100%
S. Trebst, U. H. E. Hansmann
We describe optimized parallel tempering simulations of the 46-residue B-fragment of protein A. Native-like configurations with a root-mean-square deviation of approximately 3A to the experimentally determined structure (Protein Data Bank identifier 1BDD) are found. However, at biologically relevant temperatures such conformations appear with only about 10%
Tom Hadfield, Ulrich Kraehmer
We complete the calculation of the twisted cyclic homology of the quantised coordinate ring of SL(2) that we began in math.QA/0405249. In particular, a nontrivial cyclic 3-cocycle is constructed which also has a nontrivial class in Hochschild cohomology and thus should be viewed as a noncommutative geometry analogue of a volume form.
Ranga-Ram Chary, Asantha Cooray, Ian Sullivan
In order to understand the origin of clustered anisotropies detected in Spitzer images between 3.6 and 8 microns, we stack the Spitzer IRAC/Great Observatories Origins Deep Survey (GOODS) images at pixel locations corresponding to faint, z_{AB}~27 mag, optical sources with no obvious IR counterparts. We obtain a strong detection of the sources with a stacked
F. L. Ning, S. M. Golin, K. Ahilan, T. Imai
The CoO$_{2}$ layers in sodium-cobaltates Na$_{x}$CoO$_{2}$ may be viewed as a spin $S=1/2$ triangular-lattice doped with charge carriers. The underlying physics of the cobaltates is very similar to that of the high $T_{c}$ cuprates. We will present unequivocal $^{59}$Co NMR evidence that below $T_{CO}\sim51 K$, the insulating ground state of the itinerant a
John Lott
If g(t) is a three-dimensional Ricci flow solution, with sectional curvatures that decay like the inverse of t and diameter that increases at most like the square root of t, then the pullback Ricci flow solution on the universal cover approaches a homogeneous expanding soliton.
Elena M. Rossi, Rosalba Perna, Frédéric Daigne
The paucity of reliable achromatic breaks in Gamma-Ray Burst afterglow light curves motivates independent measurements of the jet aperture. Serendipitous searches of afterglows, especially at radio wavelengths, have long been the classic alternative. These survey data have been interpreted assuming a uniformly emitting jet with sharp edges (``top-hat'
A small cosmological constant from the modified Brans-Dicke theory - an interplay between different energy scales
gr-qcMikhail N. Smolyakov
In this paper we discuss a model in which the energy density, corresponding to the effective cosmological constant, after the $SU(2)\times U(1)$ symmetry breaking appears to be of the desired order of $10^{-48}÷10^{-47} GeV^{4}$. The model contain two different energy scales, one of which is associated with the Higgs's vacuum expectation value. Another s
Cusps and shocks in the renormalized potential of glassy random manifolds: How Functional Renormalization Group and Replica Symmetry Breaking fit together
cond-mat.dis-nnPierre Le Doussal, Markus Mueller, Kay Joerg Wiese
We compute the Functional Renormalization Group (FRG) disorder- correlator function R(v) for d-dimensional elastic manifolds pinned by a random potential in the limit of infinite embedding space dimension N. It measures the equilibrium response of the manifold in a quadratic potential well as the center of the well is varied from 0 to v. We find two distinct
A. Zheludev, V. O. Garlea, L. -P. Regnault, H. Manaka
Temperature dependencies of gap energies and magnon lifetimes are measured in the quasi-1-dimensional S=1/2 gapped quantum magnets IPA-CuCl3 and Sul-Cu2Cl4 using inelastic neutron scattering. The results are compared to those found in literature for S=1 Haldane spin chain materials and to theoretical calculations for the O(3)- and O(N)- quantum non-linear si
A. Figotin, I. Vitebskiy
We study electromagnetic properties of periodic composite structures, such as photonic crystals, involving lossy components. We show that in many cases a properly designed periodic structure can dramatically suppress the losses associated with the absorptive component, while preserving or even enhancing its useful functionality. As an example, we consider ma
Dusa McDuff
This note describes some recent results about the homotopy properties of Hamiltonian loops in various manifolds, including toric manifolds and one point blow ups. We describe conditions under which a circle action does not contract in the Hamiltonian group, and construct an example of a loop $\ga$ of diffeomorphisms of a symplectic manifold M with the proper
Quantum transport in a resonant tunnel junction coupled to a nanomechanical oscillator
cond-mat.mes-hallM Tahir, A MacKinnon
We discuss the quantum transport of electrons through a resonant tunnel junction coupled to a nanomechanical oscillator at zero temperature. By using the Green's function technique we calculate the transport properties of electrons through a single dot strongly coupled to a single oscillator. We consider a finite chemical potential difference between the
M. Bertola, M. Gekhtman, J. Szmigielski
The contents of the paper is now covered in two separate papers arXiv:0904.2188 and arXiv:0904.2602. Please refer to those. Note that you can still access the original version arXiv:0711.4082v1.
James Pickering
We show that if R is a compact domain in the complex plane with two or more holes and an anticonformal involution onto itself (or equivalently a hyperelliptic Schottky double), then there is an operator T which has R as a spectral set, but does not dilate to a normal operator with spectrum on the boundary of R.
Mitchell C. Begelman, Elena M. Rossi, Philip J. Armitage
We study the structure and evolution of "quasistars", accreting black holes embedded within massive hydrostatic gaseous envelopes. These configurations may model the early growth of supermassive black hole seeds. The accretion rate onto the black hole adjusts so that the luminosity carried by the convective envelope equals the Eddington limit for the
R. A. Duine, C. Morais Smith
We present a model for current-driven motion of a magnetic domain-wall line, in which the dynamics of the domain wall is equivalent to that of an overdamped vortex line in an anisotropic pinning potential. This potential has both extrinsic contributions due to, e.g., sample inhomogeneities, and an intrinsic contribution due to magnetic anisotropy. We obtain
Christian Schnell
Let X be a smooth complex projective variety of dimension d. We show that its primitive cohomology in degree d is generated by certain "tube classes," constructed from the monodromy of the family of smooth hyperplane sections on X. The proof makes use of a result about the group cohomology of certain representations that may be of independent interes
A. E. Dementyev, D. G. Cory, C. Ramanathan
We report record high Si-29 spin polarization obtained using dynamic nuclear polarization in microcrystalline silicon powder. Unpaired electrons in this silicon powder are due to dangling bonds in the amorphous region of this intrinsically heterogeneous sample. Si-29 nuclei in the amorphous region become polarized by forced electron-nuclear spin flips driven
Ana Granados, Manuel Cebrian, David Camacho, Francisco de B. Rodriguez
In this paper we apply different techniques of information distortion on a set of classical books written in English. We study the impact that these distortions have upon the Kolmogorov complexity and the clustering by compression technique (the latter based on Normalized Compression Distance, NCD). We show how to decrease the complexity of the considered bo
O. Melchert, A. K. Hartmann
We describe a percolation problem on lattices (graphs, networks), with edge weights drawn from disorder distributions that allow for weights (or distances) of either sign, i.e. including negative weights. We are interested whether there are spanning paths or loops of total negative weight. This kind of percolation problem is fundamentally different from conv
FFLO state in 1, 2, and 3 dimensional optical lattices combined with a non-uniform background potential
cond-mat.supr-conT. K. Koponen, T. Paananen, J. -P. Martikainen, M. R. Bakhtiari
We study the phase diagram of an imbalanced two-component Fermi gas in optical lattices of 1-3 dimensions, considering the possibilities of the FFLO, Sarma/breached pair, BCS and normal states as well as phase separation, at finite and zero temperatures. In particular, phase diagrams with respect to average chemical potential and the chemical potential diffe
L. Anchordoqui, V. Barger, H. Goldberg, D. Marfatia
Within the context of mass-varying neutrinos, we construct a cosmological model that has a phase transition in the electromagnetic fine structure constant αat a redshift of 0.5. The model accommodates hints of a time variable αin quasar spectra and the nonobservance of such an effect at very low redshifts. It is consistent with limits from the recombination
Marc Freitag
In young star clusters, the density can be high enough and the velocity dispersion low enough for stars to collide and merge with a significant probability. This has been suggested as a possible way to build up the high-mass portion of the stellar mass function and as a mechanism leading to the formation of one or two very massive stars (M > 150 Msun) throug
Mauricio Mondragon, Luis Lopez
Our main purpose here is to study some qualitative aspects of space and time. These include the notion of space and time regarded as the containers of respectively bodies and events, the divisibility of space, and the unrepeatability of events. We thereof argue that the ideas of an empty space, portions of empty space and a homogenous space are misleading wh
The Interaction Between Multi-Overlaps in the High Temperature Phase of the Sherrington-Kirkpatrick Spin Glass
math.PRNicholas Crawford
We explore the joint behavior of a finite number of multi-overlaps in the high temperature phase of the SK model. Extending work by M. Talagrand, we show that, when these objects are scaled to have non-trivial limiting distributions, the joint behavior is described by a Gaussian process with an explicit covariance structure.
Measurement of the cross section for W-boson production in association with jets in ppbar collisions at sqrt(s)=1.96 TeV
hep-exT. Aaltonen
We present a measurement of the cross section for W-boson production in association with jets in pbar-p collisions at sqrt(s)=1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb^-1 collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algor
Gijs Katgert, Matthias E. Möbius, Martin van Hecke
The shear flow of two dimensional foams is probed as a function of shear rate and disorder. Disordered foams exhibit strongly rate dependent velocity profiles, whereas ordered foams show rate independence. Both behaviors are captured quantitatively in a simple model based on the balance of the time-averaged drag forces in the foam, which are found to exhibit
Jan Janas, Serguei Naboko, Günter Stolz
Bounds on the exponential decay of generalized eigenfunctions of bounded and unbounded selfadjoint Jacobi matrices are established. Two cases are considered separately: (i) the case in which the spectral parameter lies in a general gap of the spectrum of the Jacobi matrix and (ii) the case of a lower semi-bounded Jacobi matrix with values of the spectral par
André Chailloux, Iordanis Kerenidis
In quantum zero knowledge, the assumption was made that the verifier is only using unitary operations. Under this assumption, many nice properties have been shown about quantum zero knowledge, including the fact that Honest-Verifier Quantum Statistical Zero Knowledge (HVQSZK) is equal to Cheating-Verifier Quantum Statistical Zero Knowledge (QSZK) (see [Wat02
Equations aux q-differences et fibres vectoriels holomorphes sur la courbe elliptique C^*/q^Z
math.QAJacques Sauloy
Nous presentons diverses applications des fibres vectoriels aux equations aux q-differences, dans la lignee de la correspondance de Weil. (We present some applications of vector bundles to $q$-difference equtions, in continuation of Weil's correspondance.)
Subwavelength imaging of light by arrays of metal-coated semiconductor nanoparticles: a theoretical study
cond-mat.mtrl-sciVassilios Yannopapas
Rigourous calculations of the imaging properties of metamaterials consisting of metal-coated semiconductor nanoparticles are presented. In particular, it is shown that under proper choice of geometric and materials parameters, arrays of such particles exhibit negative refractive index within the region of the excitonic resonance of the semiconductor. The occ
S. Y. BenZvi, B. M. Connolly, S. Westerhoff
Searches for statistically significant correlations between arrival directions of ultra-high energy cosmic rays and classes of astrophysical objects are common in astroparticle physics. We present a method to test potential correlation signals of a priori unknown strength and evaluate their statistical significance sequentially, i.e., after each incoming new
Quantum interference phenomena in four-wave mixing processes in a cavity driven by quantized fields
quant-phPengbo Li
This paper has been withdrawn by the author due to some problems.
Interpr\'etation de l'Arithm\'etique dans certains groupes de permutations affines par morceaux d'un intervalle
math.LOTuna Altınel, Alexey Muranov
The Arithmetic is interpreted in all the groups of Richard Thompson and Graham Higman, as well as in other groups of piecewise affine permutations of an interval which generalize the groups of Thompson and Higman. In particular, the elementary theories of all these groups are undecidable. Moreover, Thompson's group $F$ and some of its generalizations interpr
Jørgen Ellegaard Andersen, Niels Leth Gammelgaard, Magnus Roed Lauridsen
We give a differential geometric construction of a connection in the bundle of quantum Hilbert spaces arising from half-form corrected geometric quantization of a prequantizable, symplectic manifold, endowed with a rigid, family of Kähler structures, all of which give vanishing first Dolbeault cohomology groups. In [And1] Andersen gave an explicit constructi
On the Induction Operation for Shift Subspaces and Cellular Automata as Presentations of Dynamical Systems
math.DSSilvio Capobianco
We consider continuous, translation-commuting transformations of compact, translation-invariant families of mappingsfrom finitely generated groups into finite alphabets. It is well-known that such transformations and spaces can be described "locally" via families of patterns and finitary functions; such descriptions can be re-used on groups larger th
S. Bayegan, M. R. Hadizadeh, M. Harzchi
A spin-isospin dependent Three-Dimensional approach based on momentum vectors for formulation of the three-nucleon bound state is presented in this paper. The three-nucleon Faddeev equations with two-nucleon interactions are formulated as a function of vector Jacobi momenta, specifically the magnitudes of the momenta and the angle between them with the inclu
W. Grimus, L. Lavoura, O. M. Ogreid, P. Osland
We derive a general expression for Delta rho (or, equivalently, for the oblique parameter T) in the SU(2) x U(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge +-1/2, and an arbitrary number of scalar SU(2) singlets. The experimental bound on Delta rho constitutes a strong constraint on the masses and mixings of the sca
F. De Fazio, Th. Feldmann, T. Hurth
We investigate sum rules for heavy-to-light transition form factors at large recoil derived from correlation functions with interpolating currents for light pseudoscalar or vector fields in soft-collinear effective theory (SCET). We consider both, factorizable and non-factorizable contributions at leading power in the Lambda/m_b expansion and to first order
R. Horvat
Classical and quantum entropic properties of holographic dark energy (HDE) are considered in view of the fact that its entropy is far more restrictive than the entropy of a black hole of the same size. In cosmological settings (in which HDE is promoted to a plausible candidate for being the dark energy of the universe), HDE should be viewed as a combined sta
Wolfgang Ochs
The lightest gluonic meson is expected with J^{PC}=0^{++}, calculations in full QCD point towards a mass of around 1 GeV. The interpretation of the scalar meson spectrum is hindered as some states are rather broad. In a largely model-independent analysis of pi+ pi- \to pi+ pi-, pi0 pi0 scattering in the region 600-1800 MeV a unique solution for the isoscalar
Masaki Asano, Shigeki Matsumoto, Masato Senami, Hiroaki Sugiyama
Phenomenology of neutralino dark matter in the minimal supersymmetric model is discussed for a scenario where the lightest Higgs boson mass is lighter than 114.4 GeV. We show that the scenario is consistent not only with many collider experiments but also with the observed relic abundance of dark matter. The allowed region may be probed by experiments of Bs
Laszlo B. Szabados
The Hamiltonian constraint of the coupled Einstein-Yang-Mills-Higgs system with a cosmological constant is shown to be a pure Poisson bracket of a dimensionless functional on the phase space and the volume of the three-space. One of its potential consequences, a restriction on the eigenstates of the volume operator in a class of canonical quantum gravity the
Statistical mechanics of a single particle in a multiscale random potential: Parisi landscapes in finite dimensional Euclidean spaces
cond-mat.dis-nnYan V Fyodorov, Jean-Philippe Bouchaud
We construct a N-dimensional Gaussian landscape with multiscale, translation invariant, logarithmic correlations and investigate the statistical mechanics of a single particle in this environment. In the limit of high dimension N>>1 the free energy of the system and overlap function are calculated exactly using the replica trick and Parisi's hierarchical
Rafał Kulik
We consider the nonparametric estimation of the density function of weakly and strongly dependent processes with noisy observations. We show that in the ordinary smooth case the optimal bandwidth choice can be influenced by long range dependence, as opposite to the standard case, when no noise is present. In particular, if the dependence is moderate the band
Dror Orgad, Oded Agam
We consider a class of interaction terms that describes correlated tunneling of composite fermions between effective Landau levels. Despite being generic and of similar strength to that of the usual density-density couplings, these terms are not included in the accepted theory of the edges of fractional quantum Hall systems. Here we show that they may lead t
Kenji Morita, Su Houng Lee
We investigate medium-induced change of mass and width of J/psi and eta_c across the phase transition in hot gluonic matter using QCD sum rules. In the QCD sum rule approach, the medium effect on heavy quarkonia is induced by the change of both scalar and twist-2 gluon condensates, whose temperature dependences are extracted from the lattice calculations of
Christofer Cronstrom, Tommi Raita
We consider the question of existence of Hamiltonians for autonomous non-holonomic mechanical systems in this paper. The approach is elementary in the sense that the existence of a Hamiltonian for a given non-holonomic system is considered to be equivalent to the existence of a non-degenerate Lagrangian for the system in question. The possible existence of s
Amand Faessler, Gianluigi Fogli, Eligio Lisi, Vadim Rodin
Estimates of nuclear matrix elements for neutrinoless double beta decay (0nu2beta) based on the quasiparticle random phase approximations (QRPA) are affected by theoretical uncertainties, which can be substantially reduced by fixing the unknown strength parameter g_pp of the residual particle-particle interaction through one experimental constraint - most no
E. Passos, K. E. L. de farias, M. A. Anacleto, E. Maciel
The problem of Chern-Simons-like term induction via quantum corrections in four-dimensions is investigated in two different cases. In the first case, we consider two distinct approaches to deal with the exact fermion propagator of the extended QED theory up to the first order in the $b$-coefficient. We find different results for distinct approaches in the sa
R. Rosenfelder
Higher-order perturbative calculations in Quantum (Field) Theory suffer from the factorial increase of the number of individual diagrams. Here I describe an approach which evaluates the total contribution numerically for finite temperature from the cumulant expansion of the corresponding observable followed by an extrapolation to zero temperature. This metho
Coupling of magnetization and structural distortions in multiferroic BiFeO3 : an ab initio density functional theory study
cond-mat.mtrl-sciHong-Jian Feng
This paper has been withdrawn by the author due to a crucial citing error in equation 4.
Milos V. Lokajicek
The main assumptions the Copenhagen quantum mechanics has been based on will be summarized and the known (not yet decided) contradiction between Einstein and Bohr will be newly analyzed. The given assumptions have been represented basically by time-dependent Schroedinger equation, to which some further assumptions have been added. Some critical comments have
Pablo Arrighi, Vincent Nesme, Reinhard Werner
We consider a graph with a single quantum system at each node. The entire compound system evolves in discrete time steps by iterating a global evolution $U$. We require that this global evolution $U$ be unitary, in accordance with quantum theory, and that this global evolution $U$ be causal, in accordance with special relativity. By causal we mean that infor
Relativistic corrections of mα^6 order to the ro-vibrational spectrum of H_2^+ and HD^+ molecular ions
physics.atom-phV. I. Korobov
The major goal of the high-precision studies of ro-vibrational states in the hydrogen molecular ions is to provide an alternative way for improving the electron-to-proton mass ratio, or the atomic mass of electron. By now the complete set of relativistic and radiative corrections have been obtained for a wide range of ro-vibrational states of H_2^+ and HD^+
C. A. Dominguez, N. F. Nasrallah, K. Schilcher
It is argued that it is valid to use QCD sum rules to determine the scalar and pseudoscalar two-point functions at zero momentum, which in turn determine the ratio of the strange to non-strange quark condensates $R_{su} = \frac{<\bar{s} s>}{<\bar{q} q>}$ with ($q=u,d$). This is done in the framework of a new set of QCD Finite Energy Sum Rules (FESR) that inv
Roman Orus, Guifre Vidal
The infinite time-evolving block decimation (iTEBD) algorithm [Phys. Rev. Lett. 98, 070201 (2007)] allows to simulate unitary evolution and to compute the ground state of one-dimensional quantum lattice systems in the thermodynamic limit. Here we extend the algorithm to tackle a much broader class of problems, namely the simulation of arbitrary one-dimension
M. V. Bondarko
The paper is suspended. The reason: as was noted by prof. H. Esnault, Theorem 2.1.1 of the previous version (as well as the related Theorem 6.1.1 of http://arxiv.org/PS_cache/math/pdf/9908/9908037v2.pdf of D. Arapura and P. Sastry) is wrong unless one assumes H to be a generic hyperplane section. Hence the proofs of all results starting from 2.3 contain gaps
Harold Francke, Eric Gawiser, Paulina Lira, Ezequiel Treister
We present the first clustering results of X-ray selected AGN at z~3. Using Chandra X-ray imaging and UVR optical colors from MUSYC photometry in the ECDF-S field, we selected a sample of 58 z~3 AGN candidates. From the optical data we also selected 1385 LBG at 2.8<z< 3.8 with R<25.5. We performed auto-correlation and cross-correlation analyses, and here we
Electronic structures and lattice dynamics of BaTiO3 and BiFeO3 : a comparative first-principles study
cond-mat.mtrl-sciHong-Jian Feng
First-principles calculations were performed to investigate the ferroelectric properties of barium titanate and bismuth ferrite, as well as phonon dispersion of BaTiO3, using density functional theory and density functional perturbation theory. Results show that the strong hybridization of Ti-O and Bi-O lead to the corresponding mechanisms for stabilizing th
Joseph B. Keller
It is shown that the first $n$ prime numbers $p_1,...,p_n$ determine the next one by the recursion equation $$ p_{n+1} =\lim\limits_{s\to +\infty} [\prod\limits^n_{k=1} (1-\frac{1}{p^s_k}) \sum\limits^\infty_{j=1} \frac{1}{j^s} -1]^{-1/s}. $$ The upper limit on the sum can be replaced by $2p_n -1$, and the result still holds.
David Garber
In the last decade, a number of public key cryptosystems based on com- binatorial group theoretic problems in braid groups have been proposed. We survey these cryptosystems and some known attacks on them. This survey includes: Basic facts on braid groups and on the Garside normal form of its elements, some known algorithms for solving the word problem in the
Proposal of a Cold-atom Realization of Quantum Maps with Hofstadter's Butterfly Spectrum
quant-phJiao Wang, Jiangbin Gong
Quantum systems with Hofstadter's butterfly spectrum are of fundamental interest to many research areas. Based upon slight modifications of existing cold-atom experiments, a cold-atom realization of quantum maps with Hofstadter's butterfly spectrum is proposed. Connections and differences between our realization and the kicked Harper model are identi
V. Krishnan
Let $(M,g)$ be a simple Riemannian manifold. Under the assumption that the metric $g$ is real-analytic, it is shown that if the geodesic ray transform of a function $f\in L^{2}(M)$ vanishes on an appropriate open set of geodesics, then $f=0$ on the set of points lying on these geodesics. The approach is based on a microlocal version of unique continuation of
Stefan Boettcher, Helmut G. Katzgraber, David Sherrington
Numerical results for the local field distributions of a family of Ising spin-glass models are presented. In particular, the Edwards-Anderson model in dimensions two, three, and four is considered, as well as spin glasses with long-range power-law-modulated interactions that interpolate between a nearest-neighbour Edwards-Anderson system in one dimension and
Clifford Lam, Jianqing Fan
This paper studies the sparsistency and rates of convergence for estimating sparse covariance and precision matrices based on penalized likelihood with nonconvex penalty functions. Here, sparsistency refers to the property that all parameters that are zero are actually estimated as zero with probability tending to one. Depending on the case of applications,
Jeffrey Burdges
One of the central tools in the classification of simple algebraic groups is the distinction between semisimple subgroups and unipotent subgroups. It is not a priori clear how to make this distinction for torsion-free subgroups of a group of finite Morley rank. We exploit the ``graded'' notion of 0-unipotence to develop a Sylow theory for torsion-fre
M. V. Perel, I. V. Fialkovsky
Exponentially localized solutions of the Klein-Gordon equation for two and three space variables are presented. The solutions depend on four free parameters. For some relations between the parameters, the solutions describe wave packets filled with oscillations whose amplitudes decrease in the Gaussian way with distance from a point running with group veloci
Christian Klingenberg, Wolfram Schmidt, Knut Waagan
The idea of this work is to compare a new positive and entropy stable approximate Riemann solver by Francois Bouchut with a state-of the-art algorithm for astrophysical fluid dynamics. We implemented the new Riemann solver into an astrophysical PPM-code, the Prometheus code, and also made a version with a different, more theoretically grounded higher order a
A. V. Bilous, V. I. Kondratiev, M. V. Popov, V. A. Soglasnov
We present a review of observed parameters of giant radio pulses, based on the observations conducted by our group during recent years. The observations cover a broad frequency range of about 3 octaves, concentrating between 600 and 4850 MHz. Giant pulses of both the Crab pulsar and the millisecond pulsar B1937+21 were studied with the 70-m Tidbinbilla, the
Paul Kiel, Jarrod Hurley, Matthew Bailes, James Murray
The majority of pulsar population synthesis studies performed to date have focused on isolated pulsar evolution. Those that have incorporated pulsar evolution within binary systems have tended to either treat binary evolution poorly of evolve the pulsar population in an ad-hoc manner. Here we present the first model of the Galactic field pulsar population th
P. Kharel, C. Sudakar, A. B. Harris, R. Naik
We report on the electric field control of magnetic phase transition temperatures in multiferroic Ni3V2O8 thin films. Using magnetization measurements, we find that the phase transition temperature to the canted antiferromagnetic state is suppressed by 0.2 K in an electric field of 30 MV/m, as compared to the unbiased sample. Dielectric measurements show tha
T. M. Antonsen, R. T. Faghih, M. Girvan, E. Ott
Large systems of coupled oscillators subjected to a periodic external drive occur in many situations in physics and biology. Here the simple, paradigmatic case of equal-strength, all-to-all sine-coupling of phase oscillators subject to a sinusoidal external drive is considered. The stationary states and their stability are determined. Using the stability inf
Frank Oertel
We list and discuss the background of some open problems, regarding the principle of local reflexivity for maximal Banach ideals.
Hua Feng, Philip Kaaret
We present Chandra and HST observations of the ultraluminous X-ray source (ULX) IC 342 X-1. The Chandra and HST images are aligned using two X-ray emitting foreground stars. The astrometry corrected position for X-1 is R.A. = 03h45m55.61s, Decl. = +68d04m55.3s (J2000) with an error circle of 0.2". One extended optical source is found in the error circle,
M. Johnston-Hollitt, R. W. Hunstead, E. Corbett
The galaxy cluster A3667 was observed using the Two-degree Field (2dF) multifibre spectroscopic system on the Anglo-Australian Telescope in a program designed to examine the velocity structure in the region. Specifically, we sought evidence from the optical data for the putative cluster merger believed to be responsible for the observed radio and X-ray emiss
Ammari Zied, Nier Francis
This article proposes the construction of Wigner measures in the infinite dimensional bosonic quantum field theory, with applications to the derivation of the mean field dynamics. Once these asymptotic objects are well defined, it is shown how they can be used to make connections between different kinds of results or to prove new ones.
Stéphane Herbert-Fort, Dennis Zaritsky, Yeun Jin Kim, Jeremy Bailin
We measure the distribution of velocities for prograde and retrograde satellite galaxies using a combination of published data and new observations for 78 satellites of 63 extremely isolated disc galaxies (169 satellites total). We find that the velocity distribution is non-Gaussian (>99.9% confidence), but that it can be described as the sum of two Gaussian