Research archive
arXiv papers from July 2009
The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.
Thomas J. Bing, Edward F. Redish
Developing expertise in physics entails learning to use mathematics effectively and efficiently as applied to the context of physical situations. Doing so involves coordinating a variety of concepts and skills including mathematical processing, computation, blending ancillary information with the math, and reading out physical implications from the math and
Hans Engler
The fractional reaction diffusion equation u_t + Au = g(u) is discussed, where A is a fractional differential operator on the real line with order \alpha between 0 and 2, the C^1 function g vanishes at 0 and 1, and either g is non-negative on (0,1) or g < 0 near 0. In the case of non-negative g, it is shown that solutions with initial support on the positive
Mikko Stenlund
For Dynamical Systems, a strong bound on multiple correlations implies the Central Limit Theorem (CLT) [ChMa]. In Chernov's paper [Ch2], such a bound is derived for dynamically Holder continuous observables of dispersing Billiards. Here we weaken the regularity assumption and subsequently show that the bound on multiple correlations follows directly from the
- Modeling Dispersive Coupling and Losses of Localized Optical and Mechanical Modes in Optomechanical Crystalsphysics.optics
Matt Eichenfield, Jasper Chan, Amir H. Safavi-Naeini, Kerry J. Vahala
Periodically structured materials can sustain both optical and mechanical excitations which are tailored by the geometry. Here we analyze the properties of dispersively coupled planar photonic and phononic crystals: optomechanical crystals. In particular, the properties of co-resonant optical and mechanical cavities in quasi-1D (patterned nanobeam) and quasi
James R. van Meter, John H. Wise, M. Coleman Miller, Christopher S. Reynolds
Coalescing massive black hole binaries are produced by the mergers of galaxies. The final stages of the black hole coalescence produce strong gravitational radiation that can be detected by the space-borne LISA. In cases where the black hole merger takes place in the presence of gas and magnetic fields, various types of electromagnetic signals may also be pr
Pawel M. Wocjan, Stephen P. Jordan, Hamed Ahmadi, Joseph P. Brennan
Suppose we are given black-box access to a finite ring R, and a list of generators for an ideal I in R. We show how to find an additive basis representation for I in poly(log |R|) time. This generalizes a quantum algorithm of Arvind et al. which finds a basis representation for R itself. We then show that our algorithm is a useful primitive allowing quantum
Chungen Liu, Duanzhi Zhang
In this paper, we first establish the Bott-type iteration formulas and some abstract precise iteration formulas of the Maslov-type index theory associated with a Lagrangian subspace for symplectic paths. As an application, we prove that there exist at least $[\frac{n}{2}]+1$ geometrically distinct brake orbits on every $C^2$ compact convex symmetric hypersur
Chih-Hao Fu
We explicitly calculate the vertices of the MHV-rules lagrangian in 4-dimensions. This proves that the vertices in the lagrangian obtained by a canonical transformation from light-cone Yang-Mills theory coincide to all order with the Parke-Taylor formula, filling the gap originally left in the lagrangian derivation of the CSW rules.
Alejandro Romanelli
We generalize the discrete quantum walk on the line using a time dependent unitary coin operator. We find an analytical relation between the long-time behaviors of the standard deviation and the coin operator. Selecting the coin time sequence allows to obtain a variety of predetermined asymptotic wave-function spreadings: ballistic, sub-ballistic, diffusive,
- Imaging Atomic and Highly Excited Molecular Gas in a z=6.42 Quasar Host Galaxy: Copious Fuel for an Eddington-Limited Starburst at the End of Cosmic Reionizationastro-ph.CO
Dominik A. Riechers, Fabian Walter, Frank Bertoldi, Christopher L. Carilli
We have imaged CO(J=7-6) and CI(3P2-3P1) emission in the host galaxy of the z=6.42 quasar SDSS J114816.64+525150.3 (hereafter: J1148+5251) through observations with the Plateau de Bure Interferometer. The region showing CO(J=7-6) emission is spatially resolved, and its size of 5 kpc is in good agreement with earlier CO(J=3-2) observations. In combination wit
Xuebin Li, Xiaosong Wu, Mike Sprinkle, Fan Ming
Three types of first generation epitaxial graphene field effect transistors (FET) are presented and their relative merits are discussed. Graphene is epitaxially grown on both the carbon and silicon faces of hexagonal silicon carbide and patterned with electron beam lithography. The channels have a Hall bar geometry to facilitate magnetoresistance measurement
- Effects due to a scalar coupling on the particle-antiparticle production in the Duffin-Kemmer-Petiau theoryhep-th
T. R. Cardoso, L. B. Castro, A. S. de Castro
The Duffin-Kemmer-Petiau formalism with vector and scalar potentials is used to point out a few misconceptions diffused in the literature. It is explicitly shown that the scalar coupling makes the DKP formalism not equivalent to the Klein-Gordon formalism or to the Proca formalism, and that the spin-1 sector of the DKP theory looks formally like the spin-0 s
- Precision analysis for standard deviation measurements of single fluorescent molecule imagesq-bio.QM
Michael C. DeSantis, Shawn H. DeCenzo, Je-Luen Li, Y. M. Wang
Standard deviation measurements of intensity profiles of stationary single fluorescent molecules are useful for studying axial localization, molecular orientation, and a fluorescence imaging system's spatial resolution. Here we report on the analysis of the precision of standard deviation measurements of intensity profiles of single fluorescent molecules ima
Jon Machta
Parallel tempering, also known as replica exchange Monte Carlo, is studied in the context of two simple free energy landscapes. The first is a double well potential defined by two macrostates separated by a barrier. The second is a `golf course' potential defined by microstates having two possible energies with exponentially more high energy states than low
Ana Pichel
Approximately 25 blazars are know to emit VHE (E>100 GeV) gamma rays. Understanding these powerful objects requires long-term, intense, monitoring observations since they exhibit strong, rapid and irregular variability across the entire electromagnetic spectrum. The Whipple 10-m Gamma-ray Telescope, the world's fourth most sensitive VHE telescope, is used pr
Christian S. Fischer, Jens A. Mueller
We determine the quark condensate and the dressed Polyakov loop from the finite temperature Landau gauge quark propagator evaluated with U(1)-valued boundary conditions in an approximation to quenched QCD. These gauge invariant quantities allow for an investigation of the chiral and deconfinement transition. We compare results from Dyson-Schwinger equations
Francisco M. Fernández
We argue that the dynamic extended molecular orbital (DEMO) method may be less accurate than expected because the motion of the center of mass was not properly removed prior to the SCF calculation. Under such conditions the virial theorem is a misleading indication of the accuracy of the wavefunction.
Paolo Amore, Francisco M. Fernandez
We study a harmonic molecule confined to a one--dimensional box with impenetrable walls. We explicitly consider the symmetry of the problem for the cases of different and equal masses. We propose suitable variational functions and compare the approximate energies given by the variation method and perturbation theory with accurate numerical ones for a wide ra
Charles Livingston, Swatee Naik
Let $M_K$ be the 2-fold branched cover of a knot $K in $S^3$. If $H_1(M_K) = {\bf Z}_3 \oplus {\bf Z}_{3^{2i}} \oplus G$ where 3 does not divide the order of $G$ then $K$ is not of order 4 in the concordance group. This obstruction detects infinite new families of knots that represent elements of order 4 in the algebraic concordance group that are not of ord
- The Lick AGN Monitoring Project: Broad-Line Region Radii and Black Hole Masses from Reverberation Mapping of Hbetaastro-ph.CO
Misty C. Bentz, Jonelle L. Walsh, Aaron J. Barth, Nairn Baliber
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~10^6-10^7 M_sun and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects i
L. Trouille, A. J. Barger, L. L. Cowie, Y. Yang
We compare the optical spectral types with the X-ray spectral properties for a uniformly selected (sources with fluxes greater than the 3 sigma level and above a flux limit of f_2-8 keV > 3.5x10^-15 erg/cm2/s), highly spectroscopically complete (>80% for f_2-8 keV > 10^-14 erg/cm2/s and >60% below) 2-8 keV X-ray sample observed in three Chandra fields (CLANS
Cristiano Germani, Alex Kehagias
We calculate the primordial spectrum of scalar perturbations of the 3-form inflation and we find that the curvature perturbations decay at late times. As as result, although a non-minimally coupled massive 3-form field may drive inflation at early times, it should be assisted by other fields in order to reproduce the observed temperature fluctuations of the
Mohammed Abouzaid
Given an exact relatively Pin Lagrangian embedding Q in a symplectic manifold M, we construct an A-infinity restriction functor from the wrapped Fukaya category of M to the category of modules on the differential graded algebra of chains over the based loop space of Q. If M is the cotangent bundle of Q, this functor induces an A-infinity equivalence between
Laszlo Erdos, Benjamin Schlein, Horng-Tzer Yau
We consider $N\times N$ symmetric random matrices where the probability distribution for each matrix element is given by a measure $\nu$ with a subexponential decay. We prove that the eigenvalue spacing statistics in the bulk of the spectrum for these matrices and for GOE are the same in the limit $N \to \infty$. Our approach is based on the study of the Dys
Guoyi Xu
In this paper, we give the first detailed proof of the short-time existence of Deane Yang's local Ricci flow. Then using the local Ricci flow, we prove short-time existence of the Ricci flow on noncompact manifolds, whose Ricci curvature has global lower bound and sectional curvature has only local average integral bound. The short-time existence of the Ricc
- A Global Treatment Of VMD Physics Up To The phi: II. tau Decay and Hadronic Contributions To g-2hep-ph
M. Benayoun, P. David, L. DelBuono, O. Leitner
Relying on the Hidden Local Symmetry (HLS) model equipped with a mechanism breaking the U(3)/SU(3)/SU(2) symmetries and generating a dynamical vector meson mixing, it has been shown that a global fit successfully describes the cross sections for the e+ e- -> pi+ pi-, e+ e- -> (pi0/eta) gamma and e+ e- -> pi0 pi+ pi- annihilation channels. One extends this gl
Joe Henson
A new procedure for coarse-graining dynamical triangulations is presented. The procedure provides a meaning for the relevant value of observables when "probing at large scales", e.g. the average scalar curvature. The scheme may also be useful as a starting point for a new type of renormalisation procedure, suitable for dynamically triangulated quantum gravit
William Brito
This thesis presents a review of related important concepts in cosmology followed by details of the author's role in a research project on the origin of intracluster light. The author's role in the development of the simulations varied from searching parameters in the literature, through writing and modifying code in IDL, FORTRAN, and UNIX to carrying out hu
- Macrostate Parameter, an Econophysics Approach for the Risk Analysis of the Stock Exchange Market Transactionsq-fin.RM
Anca Gheorghiu, Ion Spanulescu
In this paper we attempt to introduce an econophysics approach to evaluate some aspects of the risks in financial markets. For this purpose, the thermodynamical methods and statistical physics results about entropy and equilibrium states in the physical systems are used. Some considerations on economic value and financial information are made. Finally, on th
I. N. Pashchenko, B. V. Komberg
Using standard cosmological model we show that the cores of ultra-compact radio sources observed with ground-based Very Long Baseline Interferometry (VLBI) on the angular scales of milliarcseconds cannot be used as a reasonable standard unit of linear size. "Luminosity - linear size" correlation obtained by many authors for ultra compact radio sources has di
- Pricing Bermudan options using nonparametric regression: optimal rates of convergence for lower estimatesq-fin.PR
Denis Belomestny
The problem of pricing Bermudan options using Monte Carlo and a nonparametric regression is considered. We derive optimal non-asymptotic bounds for a lower biased estimate based on the suboptimal stopping rule constructed using some estimates of continuation values. These estimates may be of different nature, they may be local or global, with the only requir
Peter de Blanc
We consider a sequence of repeated interactions between an agent and an environment. Uncertainty about the environment is captured by a probability distribution over a space of hypotheses, which includes all computable functions. Given a utility function, we can evaluate the expected utility of any computational policy for interaction with the environment. A
Qinglan Xia
An optimal transport path may be viewed as a geodesic in the space of probability measures under a suitable family of metrics. This geodesic may exhibit a tree-shaped branching structure in many applications such as trees, blood vessels, draining and irrigation systems. Here, we extend the study of ramified optimal transportation between probability measures
Steven J. Pollock
We have investigated the long-term effect of student-centered instruction at the freshman level on juniors' performance on a conceptual survey of Electricity and Magnetism (E&M). We measured student performance on a research-based conceptual instrument -- the Brief Electricity & Magnetism Assessment (BEMA) -- over a period of 8 semesters (2004-2007). Concurr
- The cleavage surface of the BaFe_(2-x)Co_(x)As_(2) and Fe_(y)Se_(1-x)Te_(x) superconductors: from diversity to simplicitycond-mat.supr-con
F. Massee, S. de Jong, Y. Huang, J. Kaas
We elucidate the termination surface of cleaved single crystals of the BaFe_(2-x)Co_(x)As_(2) and Fe_(y)Se_(1-x)Te_(x) families of the high temperature iron based superconductors. By combining scanning tunneling microscopic data with low energy electron diffraction we prove that the termination layer of the Ba122 systems is a remnant of the Ba layer, which e
E. I. Bunina
In the paper we prove that every automorphism of a (elementary) Chevalley group of type $A_l, D_l$, or $E_l$, $l\geqslant 2$, over a commutative local ring with 1/2 is standard, i. e., is the composition of inner, ring, graph and central automorphisms.
- Automorphisms and isomorphisms of Chevalley groups of type $G_2$ over local rings with 1/2 and 1/3math.GR
E. I. Bunina
We prove that every isomorphism of Chevalley groups of type $G_2$ over commutative local rings with 1/2 and 1/3 is standard, i. e., it is a composition of a ring isomorphism and an inner automorphism.
Nima Arkani-Hamed, Freddy Cachazo, Clifford Cheung, Jared Kaplan
We propose a dual formulation for the S Matrix of N = 4 SYM. The dual provides a basis for the "leading singularities" of scattering amplitudes to all orders in perturbation theory, which are sharply defined, IR safe data that uniquely determine the full amplitudes at tree level and 1-loop, and are conjectured to do so at all loop orders. The scattering ampl
- Non-Perturbative Asymptotic Improvement of Perturbation Theory and Mellin-Barnes Representationhep-th
Samuel Friot, David Greynat
Using a method mixing Mellin-Barnes representation and Borel resummation we show how to obtain hyperasymptotic expansions from the (divergent) formal power series which follow from the perturbative evaluation of arbitrary "$N$-point" functions for the simple case of zero-dimensional $\phi^4$ field theory. This hyperasymptotic improvement appears from an iter
E. I. Bunina
In the paper we prove that every automorphism of a Chevalley group of type $F_4$ over a commutative local ring with~1/2 is standard, i. e., it is a composition of ring and inner automorphisms.
Thomas Cailleteau, Parampreet Singh, Kevin Vandersloot
We study the role of non-perturbative quantum gravity effects in the Ekpyrotic/Cyclic model using the effective framework of loop quantum cosmology in the presence of anisotropies. We show that quantum geometric modifications to the dynamical equations near the Planck scale as understood in the quantization of Bianchi-I spacetime in loop quantum cosmology le
- Generalized differentiation with positively homogeneous maps: Applications in set-valued analysis and metric regularitymath.OC
C. H. Jeffrey Pang
We propose a new concept of generalized differentiation of set-valued maps that captures the first order information. This concept encompasses the standard notions of Frechet differentiability, strict differentiability, calmness and Lipschitz continuity in single-valued maps, and the Aubin property and Lipschitz continuity in set-valued maps. We present calc
David S. Herscovici, Benjamin D. Hester, Glenn H. Hurlbert
We prove a generalization of Graham's Conjecture for optimal pebbling with arbitrary sets of target distributions. We provide bounds on optimal pebbling numbers of products of complete graphs and explicitly find optimal $t$-pebbling numbers for specific such products. We obtain bounds on optimal pebbling numbers of powers of the cycle $C_5$. Finally, we pres
Tom Bohman, Alan Frieze, Michael Krivelevich, Po-Shen Loh
The classical result in the theory of random graphs, proved by Erdos and Renyi in 1960, concerns the threshold for the appearance of the giant component in the random graph process. We consider a variant of this problem, with a Ramsey flavor. Now, each random edge that arrives in the sequence of rounds must be colored with one of R colors. The goal can be ei
- On the Sunyaev-Zel'dovich effect from dark matter annihilation or decay in galaxy clustersastro-ph.CO
Julien Lavalle, Celine Boehm, Julien Barthes
We revisit the prospects for detecting the Sunyaev Zel'dovich (SZ) effect induced by dark matter (DM) annihilation or decay. We show that with standard (or even extreme) assumptions for DM properties, the optical depth associated with relativistic electrons injected from DM annihilation or decay is much smaller than that associated with thermal electrons, wh
A. D. Alhaidari
We present a resolution of the Klein paradox within the framework of one-particle relativistic quantum mechanics. Not only reflection becomes total but the vacuum remains neutral as well. This is accomplished by replacing the pair production process with virtual negative energy "incidence" within the barrier in a similar manner to what is done with image cha
- Systematic analysis of finite family symmetry groups and their application to the lepton sectorhep-ph
Patrick Otto Ludl
In this work we will investigate Lagrangians of the standard model extended by three right-handed neutrinos, and the consequences of invariance under finite groups G for lepton masses and mixing matrices are studied. The main part of this work is the systematic analysis of finite subgroups of SU(3). The analysis of these groups may act as a toolkit for futur
J. Cerrillo, A. Retzker, M. B. Plenio
We present a robust and fast laser cooling scheme suitable for trapped atoms and ions. Based on quantum interference, generated by a special laser configuration, it is able to rapidly cool the system such that the final phonon occupation vanishes to zeroth order in the Lamb-Dicke parameter in contrast to existing cooling schemes. Furthermore, it is robust un
Eric Perim, Douglas S. Galvao
Carbon nanoscrolls (CNSs) are structures formed by rolling up graphene layers into a papyruslike shape. CNNs have been experimentally produced by different groups. Boron nitride nanoscrolls (BNNSs) are similar structures using boron nitride instead of graphene layers. In this work we report molecular mechanics and molecular dynamics results for the structura
M. A. Lledo, L. Sommovigo
We make it precise what it means to have a connection with torsion as solution of the Einstein equations. While locally the theory remains the same, the new formulation allows for topologies that would have been excluded in the standard formulation of gravity. In this formulation it is possible to couple arbitrary torsion to gauge fields without breaking the
- Unicity of the integrated density of states for relativistic Schroedinger operators with regular fields and singular electric potentialsmath.SP
Viorel Iftimie, Marius Mantoiu, Radu Purice
We show coincidence of the two definitions of the integrated density of states (IDS) for a class of relativistic Schroedinger operators with magnetic fields and scalar potentials, the first one relying on the eigenvalue counting function of operators induced on open bounded sets with Dirichlet boundary conditions, the other one involving the spectral project
S. R. Clark, J. Prior, M. J. Hartmann, D. Jaksch
In recent work Hartmann et al [Phys. Rev. Lett. 102, 057202 (2009)] demonstrated that the classical simulation of the dynamics of open 1D quantum systems with matrix product algorithms can often be dramatically improved by performing time evolution in the Heisenberg picture. For a closed system this was exemplified by an exact matrix product operator solutio
Jonathan Henry Brown
In 1990, Rieffel defined a notion of proper action of a group $H$ on a $C^*$-algebra $A$. He then defined a generalized fixed point algebra $A^{\alpha}$ for this action and showed that $A^{\alpha}$ is Morita equivalent to an ideal of the reduced crossed product. We generalize Rieffel's notion to define proper groupoid dynamical systems and show that the gene
Beatriz de Carlos, Adolfo Guarino, Jesus M. Moreno
We perform a complete classification of the flux-induced 12d algebras compatible with the set of N=1 type II orientifold models that are T-duality invariant, and allowed by the symmetries of the T^6/(Z_2 x Z_2) isotropic orbifold. The classification is performed in a type IIB frame, where only H_3 and Q fluxes are present. We then study no-go theorems, formu
Irakli Garishvili
The fisrt measurement of the nuclear modification factor for single muons produced in CuCu collisions is presented which is the first measurement of the nuclear modification factor for open heavy flavor production made at forward angles in heavy ion collisions
Lucile Sassatelli, Muriel Medard
This article has been withdrawn by the authors
Andrew D. Warshall
We introduce the concepts of a pair of valuations and a good generating set and show how they can be used to prove geometric properties of soluble groups.
Gerald E. Marsh
It has been argued that the limited set of proteins used by life as we know it could not have arisen by the process of Darwinian selection from all possible proteins. This probabilistic argument has a number of implicit assumptions that may not be warranted. A variety of considerations are presented to show that the number of amino-acid sequences that need h
M. Janoschek, F. Bernlochner, S. Dunsiger, C. Pfleiderer
MnSi is a cubic compound with small magnetic anisotropy, which stabilizes a helimagnetic spin spiral that reduces to a ferromagnetic and antiferromagnetic state in the long- and short-wavelength limit, respectively. We report a comprehensive inelastic neutron scattering study of the collective magnetic excitations in the helimagnetic state of MnSi. In our st
Pascal Koiran
A polynomial identity testing algorithm must determine whether a given input polynomial is identically equal to 0. We give a deterministic black-box identity testing algorithm for univariate polynomials of the form $\sum_{j=0}^t c_j X^{\alpha_j} (a + b X)^{\beta_j}$. From our algorithm we derive an exponential lower bound for representations of polynomials s
S. -H. Baek, N. J. Curro, K. -Y. Choi, A. P. Reyes
We report detailed 51V NMR spectra in a single crystal of MnV2O4. The vanadium spectrum reveals two peaks in the orbitally ordered state, which arise from different internal hyperfine fields at two different V sublattices. These internal fields evolve smoothly with externally applied field, and show no change in structure that would suggest a change of the o
Harald Appelshauser, Stefan Kniege
A high statistics study of high-$p_t$ two-particle azimuthal correlations in Pb-Au at $\sqrt{s_{\rm NN}}=17.2$ GeV, performed by the CERES experiment at the CERN-SPS, is presented. A broad away-side correlation with significant dip at $\Delta\phi\approx\pi$ is observed. The shape and magnitude of the correlation is similar to measurements at RHIC. In compari
- Comment on the article "Existence and Regularity for an Energy Maximization Problem in Two Dimensions" by Spyridon Kamvissis, Evguenii A. Rakhmanovmath.CV
Spyridon Kamvissis
A revised version of the last appendix of the (previous) paper "Existence and Regularity for an Energy Maximization Problem in Two Dimensions" by S.Kamvissis and E.A.Rakhmanov, that appeared in the Journal of Mathematical Physics, v.46, n.8, 2005. arXiv:0907.5571
Vadim V. Shurygin
In the present paper, we study complete and vertical lifts of tensor fields from a smooth manifold $M$ to its Weil bundle $T^A M$ defined by a Frobenius Weil algebra $A$. For a Poisson manifold $(M,w)$, we show that the complete lift $w^C$ and the vertical lift $w^V$ of the Poisson tensor $w$ are Poisson tensors on $T^A M$ and establish their properties. We
Spyridon Kamvissis, Evguenii A. Rakhmanov
We consider the variational problem of maximizing the weighted equilibrium Green's energy of a distribution of charges free to move in a subset of the upper half-plane, under a particular external field. We show that this problem admits a solution and that, under some conditions, this solution is an S-curve (in the sense of Gonchar-Rakhmanov). The above prob
A. S. Usenko
We propose a self-consistent model taking into account variations in adsorption properties of the adsorbent surface in the process of adsorption--desorption of molecules of gas on it. We introduce a dimensionless coupling parameter that characterizes the interaction of an adsorbed molecule with polarized medium. It is established that the system can be bista
- Likelihood Functions for Supersymmetric Observables in Frequentist Analyses of the CMSSM and NUHM1hep-ph
O. Buchmueller, R. Cavanaugh, A. De Roeck, J. R. Ellis
On the basis of frequentist analyses of experimental constraints from electroweak precision data, g-2, B physics and cosmological data, we investigate the parameters of the constrained MSSM (CMSSM) with universal soft supersymmetry-breaking mass parameters, and a model with common non-universal Higgs masses (NUHM1). We present chi^2 likelihood functions for
Benjamin C. Bromley, Scott J. Kenyon, Warren R. Brown, Margaret J. Geller
Runaway stars ejected from the Galactic disk populate the halo of the Milky Way. To predict the spatial and kinematic properties of runaways, we inject stars into a Galactic potential, compute their trajectories through the Galaxy, and derive simulated catalogs for comparison with observations. Runaways have a flattened spatial distribution, with higher velo
T. Frederico, E. Pace, B. Pasquini, G. Salmé
We investigate the model dependence of no-helicity flip generalized parton distribution of the pion upon different approaches for the quark-hadron and quark-photon vertexes, in the spacelike region. In order to obtain information on contributions from both the valence and non-valence regions, we compare results for spacelike momentum transfers obtained from
G. Gentili, C. Stoppato
A new class of regular quaternionic functions, defined by power series in a natural fashion, has been introduced in recent years. Several results of the theory recall the classical complex analysis, whereas other results reflect the peculiarity of the quaternionic structure. A more recent paper identified a larger class of domains, on which the study of regu
M. Syafwan, H. Susanto, S. M. Cox
We consider a parametrically driven Klein--Gordon system describing micro- and nano-devices, with integrated electrical and mechanical functionality. Using a multiscale expansion method we reduce the system to a discrete nonlinear Schrodinger equation. Analytical and numerical calculations are performed to determine the existence and stability of fundamental
- MUPAGE: a fast atmospheric MUon GEnerator for neutrino telescopes based on PArametric formulasastro-ph.IM
G. Carminati, M. Bazzotti, S. Biagi, S. Cecchini
Neutrino telescopes are opening new opportunities in observational high energy astrophysics. In these detectors, atmospheric muons from primary cosmic ray interactions in the atmosphere play an important role. They provide the most abundant source of events for calibration and for testing the reconstruction algorithms. On the other hand, they represent the m
Patrick Joly, Ricardo Weder
We study the propagation of acoustic waves in a fluid that is contained in a thin two-dimensional tube, and that it is moving with a velocity profile that only depends on the transversal coordinate of the tube. The governing equations are the Galbrun equations, or, equivalently, the linearized Euler equations. We analyze the approximate model that was recent
- On the Selberg integral of the $k-$divisor function and the $2k-$th moment of the Riemann zeta functionmath.NT
Giovanni Coppola
We deeply appreciate the papers of Ivi\'c on the links between the $2k-$th moments of the Riemann zeta function and, say, $d_k$, the $k-$divisor function. More specifically, both the one bounding the $2k-$th moment with a simple average of correlations of the $d_k$ (Palanga 1996 Conference Proceedings) and the more recent (arXiv:0708.1601v2 to appear on JTNB
Riccardo Fantoni, Achille Giacometti, Alexandr Malijevský, Andrés Santos
We study structural and thermophysical properties of a one-dimensional classical fluid made of penetrable spheres interacting via an attractive square-well potential. Penetrability of the spheres is enforced by reducing from infinite to finite the repulsive energy barrier in the pair potentials As a consequence, an exact analytical solution is lacking even i
- From WMAP to Planck: Exact reconstruction of 4- and 5-dimensional inflationary potential from high precision CMB measurementsastro-ph.CO
L. A. Popa, N. Mandolesi, A. Caramete, C. Burigana
We make a more general determination of the inflationary observables in the standard 4-D and 5-D single-field inflationary scenarios, by the exact reconstruction of the dynamics of the inflation potential during the observable inflation with minimal number of assumptions: the computation does not assume the slow-roll approximation and is valid in all regimes
S. A. Tarasenko
The theory of spin relaxation of conduction electrons is developed for zinc-blende-type quantum wells grown on (110)-oriented substrate. It is shown that, in asymmetric structures, the relaxation of electron spin initially oriented along the growth direction is characterized by two different lifetimes and leads to the appearance of an in-plane spin component
Yin Lu, Christian Miniatura, Berthold-Georg Englert
The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower bounds. The up
Brian C. Rushton
The study of geometric group theory has suggested several theorems related to subdivision tilings that have a natural hyperbolic structure. However, few examples exist. We construct subdivision tilings for the complement of every nonsingular, prime alternating link. These tilings define a combinatorial space at infinity, similar to the space at infinity for
O. Sotolongo-Grau, D. Rodriguez-Perez, J. A. Santos-Miranda, J. C. Antoranz
The expression of survival factors for radiation damaged cells is empirical and based on probabilistic assumptions. We obtain it either from the maximum entropy principle for the classical Boltzmann-Gibbs entropy and/or from the Tsallis entropy. Empiric models are found to be particular cases of the obtained expression. The survival factor exhibits a phase t
Hsien-Chung Kao, Wen-Yu Wen
We investigate the absorption cross section for minimal-coupled scalars in the warped AdS_3 black hole. According to our calculation, the cross section reduces to the horizon area in the low energy limit as usually expected in contrast to what was previously found. We also calculate the greybody factor and find that the effective temperatures for the two chi
- Variational equivalence between Ginzburg-Landau, XY spin systems and screw dislocations energiesmath-ph
R. Alicandro, M. Cicalese, M. Ponsiglione
We introduce and discuss discrete two-dimensional models for XY spin systems and screw dislocations in crystals. We prove that, as the lattice spacing $\e$ tends to zero, the relevant energies in these models behave like a free energy in the complex Ginzburg-Landau theory of superconductivity, justifying in a rigorous mathematical language the analogies betw
Ayla Gafni
This note examines a problem in enumerative and asymptotic combinatorics involving the classical structure of integer compositions. What is sought is an analysis on average and in distribution of the length of the longest run of consecutive equal parts in a composition of size n. The problem was recently posed by Herbert Wilf (see arXiv: 0906.5196).
L. Isenhower, E. Urban, X. L. Zhang, A. T. Gill
We present the first demonstration of a CNOT gate using neutral atoms. Our implementation of the CNOT uses Rydberg blockade interactions between neutral atoms held in optical traps separated by >8 \mu\rm m. We measure CNOT fidelities of F=0.73 and 0.72 using two different gate protocols, and show by measurement of parity oscillations that the gate can be use
- Deterministically entangling distant nitrogen-vacancy centers by a nanomechanical cantileverquant-ph
Z. Y. Xu, Y. M. Hu, W. L. Yang, M. Feng
We present a practical scheme by global addressing to deterministically entangle negatively charged nitrogen-vacancy (N-V) centers in distant diamonds using a nano-mechanical cantilever with the magnetic tips strongly coupled to the N-V electron spins. Symmetric Dicke states are generated as an example, and the experimental feasibility and challenge of our s
Lan-Hsuan Huang, Damin Wu
We study the curvature condition which uniquely characterizes the hemisphere. In particular, we prove the Min-Oo conjecture for hypersurfaces in Euclidean space and hyperbolic space.
- Magnetism and superconductivity in single crystals $Eu_{1-x}Sr_xFe_{2-y}Co_{y}As_2$cond-mat.supr-con
Q. J. Zheng, Y. He, T. Wu, G. Wu
We systematically studied the transport properties of single crystals of $Eu_{1-x}Sr_xFe_{2-y}$Co$_{y}As_2$. Co doping can suppress the spin-density wave (SDW) ordering and induces a superconducting transition, but a resistivity reentrance due to the antiferromagnetic ordering of $Eu^{2+}$ spins is observed, indicating the competition between antiferromagnet
Cesar R. de Oliveira, Mariza S. Simsen
Let $U_F$ be the Floquet operator of a time periodic hamiltonian $H(t)$. For each positive and discrete observable $A$ (which we call a {\em probe energy}), we derive a formula for the Laplace time average of its expectation value up to time $T$ in terms of its eigenvalues and Green functions at the circle of radius $e^{1/T}$. Some simple applications are pr
J. J. Rodriguez-Vega, W. A. Zuniga-Galindo
We study the solutions of equations of type $f(D,\alpha)u=v$, where $f(D,\alpha)$ is a $p$-adic pseudo-differential operator. If $v$ is a Bruhat-Schwartz function, then there exists a distribution $E_{\alpha}$, a fundamental solution, such that $u=E_{\alpha}\ast v$ is a solution. However, it is unknown to which function space $E_{\alpha}\ast v$ belongs. In t
Clement Dunand
Let p and r be two primes and n, m be two distinct divisors of pr. Consider the n-th and m-th cyclotomic polynomials. In this paper, we present lower and upper bounds for the coefficients of the inverse of one of them modulo the other one. We mention an application to torus-based cryptography.
Paul McFadden, Kostas Skenderis
We propose a holographic description of four-dimensional single-scalar inflationary universes, and show how cosmological observables, such as the primordial power spectrum, are encoded in the correlation functions of a three-dimensional QFT. The holographic description correctly reproduces standard inflationary predictions in the limit where a perturbative q
Jose M. Espinar, Isabel Fernandez
Following ideas of Choe and Fernandez-do Carmo, we give sufficient conditions for a disk type surface, with piecewise smooth boundary, to be totally umbilical for a given Coddazi pair. As a consequence, we obtain rigidity results for surfaces in space forms and in homogeneous product spaces that generalizes some known results.
Francesco Carraro, Sergio Fonte, Diego Turrini, Maria Cristina De Sanctis
Planetary sciences can benefit from several different sources of information, i.e. ground-based or near Earth-based observations, space missions and laboratory experiments. The data collected from these sources, however, are spread over a number of smaller, separate communities and stored through different facilities: this makes it difficult to integrate the
P. Roig
We study two and three meson decays of the tau lepton within the framework of the Resonance Chiral Theory, that is based on the following properties of QCD: its chiral symmetry in the massless case, its large-N_C limit, and the asymptotic behaviour it demands to the relevant form factors. Most of the couplings in the Lagrangian are determined this way render
Leah B. Shaw, Ira B. Schwartz
We study vaccine control for disease spread on an adaptive network modeling disease avoidance behavior. Control is implemented by adding Poisson distributed vaccination of susceptibles. We show that vaccine control is much more effective in adaptive networks than in static networks due to an interaction between the adaptive network rewiring and the vaccine a
Rodrigo P. Negreiros, Fridolin Weber, Manuel Malheiro, Vladimir Usov
The possible existence of compact stars made of absolutely stable strange quark matter--referred to as strange stars--was pointed out by E. Witten almost a quarter of a century ago. One of the most amazing features of such objects concerns the possible existence of ultra-strong electric fields on their surfaces, which, for ordinary strange matter, is around
Roland Diehl
Gamma-ray telescopes are capable of measuring radioactive trace isotopes from cosmic nucleosynthesis events. Such measurements address new isotope production rather directly for a few key isotopes such as 44Ti, 26Al, 60Fe, and 56Ni, as well as positrons from the beta^+-decay variety. Experiments of the past decades have now established an astronomy with gamm
C. Trachternach, W. J. G. de Blok, S. S. McGaugh, J. M. van der Hulst
The baryonic Tully-Fisher relation (BTF) is a fundamental relation between baryonic mass and maximum rotation velocity. It can be used to estimate distances, as well as to constrain the properties of dark matter and its relation with the visible matter. In this paper, we explore if extremely low-mass dwarf galaxies follow the same BTF relation as high-mass g
R. Paiva, R. Muhammad, R. Shiozaki, A. L. de Oliveira
Motivated by recent interest in low dimensional arrays of atoms, we experimentally investigated the way cold collisional processes are affected by the geometry of the considered atomic sample. More specifically, we studied the case of photoassociative ionization (PAI) both in a storage ring where collision is more unidirectional in character and in a trap wi
Carmen Vierheilig, Johannes Hausinger, Milena Grifoni
We consider the dissipative dynamics of a qubit coupled to a nonlinear oscillator (NO) embedded in an Ohmic environment. By treating the nonlinearity up to first order and applying Van Vleck perturbation theory up to second order in the qubit-NO coupling, we derive an analytical expression for the eigenstates and eigenfunctions of the coupled qubit-NO system