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Results for "Alexander J. Dear"

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Effect of disorder on condensation in the lattice gas model on a random graphSep 09 2013Aug 25 2014The lattice gas model of condensation in a heterogeneous pore system, represented by a random graph of cells, is studied using an exact analytical solution. A binary mixture of pore cells with different coordination numbers is shown to exhibit two phase ... More
Geometric localization in supported elastic strutsJun 11 2019Localized deformation patterns are a common motif in morphogenesis and are increasingly finding widespread applications in materials science, for instance as memory devices. Here we describe the emergence of spatially localized deformations in a minimal ... More
Exactly solvable quantum state reduction models with time-dependent couplingNov 06 2005Jul 10 2006A closed-form solution to the energy-based stochastic Schrodinger equation with a time-dependent coupling is obtained. The solution is algebraic in character, and is expressed directly in terms of independent random data. The data consist of (i) a random ... More
The Hadronic Transitions $Upsilon(2S)\to Upsilon(1S)$Feb 27 1998Using a data sample of $\Upsilon(2S)$ events collected with the CLEO II detector at the Cornell Electron Storage Ring, we have investigated the hadronic transitions between the $\Upsilon(2S)$ and the $\Upsilon(1S)$. The charged dipion transition $\Upsilon(2S)\to ... More
Derivation of a non-objective Oldroyd model from the Boltzmann equationMay 03 2001I calculate the hydrodynamic limit of the BGK approximation of the Boltzmann equation for the case of a long stress relaxation time and find that the stress obeys a viscoelastic constitutive equation. The constitutive equation is different from standard ... More
Dynamics of a tensor polarization of particles and nuclei and its influence on the spin motion in external fieldsNov 14 2018The tensor polarization of particles and nuclei is constant in a coordinate system rotating with the same angular velocity as the spin. In the laboratory frame, it rotates with this angular velocity. The general equation defining the evolution of the ... More
Absolute Measurement of Hadronic Branching Fractions of the D_s^+ MesonJan 04 2008Apr 24 2008The branching fractions of D_s meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 /pb of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for eight ... More
First Observation of B -> D(*) rho', rho' -> omega pi-Mar 15 2001Jun 21 2001We report on the observation of B-> D(*) pi+ pi- pi- pi^o decays. The branching ratios for D*+ and D*o are (1.72+/-0.14+/-0.24)% and (1.80+/-0.24+/-0.27)%, respectively. Each final state has a D* omega pi- component, with branching ratios (0.29+/-0.03+/-0.04)% ... More
Evidence of New States Decaying into $Ξ_{c}^{*}π$Jun 08 1999Jun 14 1999Using data recorded by the CLEO II detector at CESR, we report evidence for two new charmed baryons, one decaying into $\Xi_c^+\pi^+\pi^-$ via an intermediate $\Xi_c^{*0}$, and its isospin partner decaying into $\Xi_c^0\pi^+\pi^-$ via an intermediate ... More
The p-width of the alternating groupsOct 13 2017Dec 08 2017Let $p$ be a fixed prime. For a finite group generated by elements of order $p$, the $p$-width is defined to be the minimal $k\in\mathbb{N}$ such that any group element can be written as a product of at most $k$ elements of order $p$. Let $A_{n}$ denote ... More
Foldy-Wouthyusen Transformation and Semiclassical Limit for Relativistic Particles in Strong External FieldsOct 23 2007Oct 30 2013A general method of the Foldy-Wouthyusen (FW) transformation for relativistic particles of arbitrary spin in strong external fields has been developed. The use of the found transformation operator is not restricted by any definite commutation relations ... More
Gleason parts and point derivations for uniform algebras with dense invertible groupJun 19 2016It is shown that there exists a compact set $X$ in ${\bf C}^N$ ($N\geq 2$) such that $\widehat X\setminus X$ is nonempty and the uniform algebra $P(X)$ has a dense set of invertible elements, a large Gleason part, and an abundance of nonzero bounded point ... More
Comparison of Spin Dynamics in the Cylindrical and Frenet-Serret Coordinate SystemsNov 25 2014A comparative analysis of a description of spin dynamics in the cylindrical and Frenet-Serret coordinate systems is carried out. An equivalence of these two systems is shown. A possibility of efficient use of the cylindrical coordinate system for a calculation ... More
An Overview of Spatial EconometricsMay 11 2016This paper offers an expository overview of the field of spatial econometrics. It first justifies the necessity of special statistical procedures for the analysis of spatial data and then proceeds to describe the fundamentals of these procedures. In particular, ... More
Uniform hyperbolicity of the graphs of nonseparating curves via bicorn curvesJul 26 2017Aug 22 2018We show that the graphs of nonseparating curves for oriented finite type surfaces are uniformly hyperbolic. Our proof closely follows the proof of uniform hyperbolicity of the graphs of curves for closed surfaces due to Przytycki-Sisto. As demonstrated ... More
Search for new physics in $B_s$-mixingAug 14 2008Nov 02 2008We present the current status of the search for new physics effects in the mixing quantities $\Delta M_s$, $\Delta \Gamma_s$ and $\phi_s$ of the neutral $B_s$-system.
On The Apparent Narrowing of Radio Recombination Lines at High Principal Quantum NumbersDec 08 2011Jan 17 2012We critically analyze the Bell et al. findings on "anomalous" widths of high-order Hydrogen radio recombination lines in the Orion Nebula at 6 GHz. We review their method of modified frequency switching and show that the way this method is used for large ... More
Nebular Abundance ErrorsApr 30 1997May 01 1997The errors inherent to the use of the standard "ionization correction factor" ("i_CF") method of calculating nebular conditions and relative abundances of H, He, N, O, Ne, S, and Ar in emission line nebulae have been investigated under conditions typical ... More
An Assympotic Vanishing Theorem for Generic Unions of Multiple PointsMar 28 1997Feb 15 2000In this revised form, the proof of the principal lemma has been simplified and the main theorem has been extended to all characteristics for those varieties which are smooth in codimension one. This principal theorem essentially says the following : given ... More
Generic Hypersurface SingularitiesMar 21 1997We give a new differential proof of our result on the maximal rank of generic unions of points of multiplicity two in projective space in degrees greater than five. This simplifies somewhat our proof of the Waring conjecture.
Analytic Discs and Uniform Algebras on Real-Analytic VarietiesJul 03 2017Oct 08 2017Under very general conditions it is shown that if $A$ is a uniform algebra generated by real-analytic functions, then either $A$ consists of all continuous functions or else there exists a disc on which every function in $A$ is holomorphic. This strengthens ... More
A doubly generated uniform algebra with a one-point Gleason part off its Shilov boundaryFeb 25 2019It is shown that there exists a compact set $X$ in ${\mathbb C}^2$ with a nontrivial polynomial hull $\widehat X$ such that some point of $\widehat X \setminus X$ is a one-point Gleason part for $P(X)$. Furthermore, $X$ can chosen so that $P(X)$ has a ... More
Connection Between Wave Functions in the Dirac and Foldy-Wouthuysen RepresentationsDec 15 2006The connection between wave functions in the Dirac and Foldy-Wouthuysen representations is found. When the Foldy-Wouthuysen transformation is exact, upper spinors in two representations differ only by constant factors, and lower spinors in the Foldy-Wouthuysen ... More
The involution width of finite simple groupsNov 21 2016For a finite group generated by involutions, the involution width is defined to be the minimal $k\in\mathbb{N}$ such that any group element can be written as a product of at most $k$ involutions. We show that the involution width of every non-abelian ... More
Spurious velocities in lattice BoltzmannJul 23 2002Stationary droplets simulated by multi-phase lattice Boltzmann methods lead to spurious velocities around them. In this article I report the origin of these spurious velocities for one example and show how they can be avoided.
General method of the relativistic Foldy-Wouthuysen transformation and proof of validity of the Foldy-Wouthuysen HamiltonianJan 09 2015Feb 04 2015A general method of the Foldy-Wouthuysen transformation is developed. This method is applicable to relativistic particles with any spin in arbitrarily strong external fields. It can be used when the de Broglie wavelength is much smaller than the characteristic ... More
Local Lorentz transformations and Thomas effect in general relativityMay 31 2016Jun 14 2016The tetrad method is used for an introduction of local Lorentz frames and a detailed analysis of local Lorentz transformations. A formulation of equations of motion in local Lorentz frames is based on the Pomeransky-Khriplovich gravitoelectromagnetic ... More
MD Simulation for Head-on Collision of Liquid Nanodroplets Obeying Modified L-J PotentialJul 04 2015This project models and studies the `head-on' collision of liquid helium nanodroplets within a vacuum, using molecular dynamics simulation techniques. Programs written in MATLAB and C are utilized in tandem to facilitate computer experimentation that ... More
Spaces with polynomial hulls that contain no analytic discsJan 07 2018Feb 25 2019Extensions of the notions of polynomially and rationally convex hulls are introduced. Using these notions, a generalization of a result of Duval and Levenberg on polynomially convex hulls containing no analytic discs is presented. As a consequence it ... More
Existence of continuous functions that are one-to-one almost everywhereAug 15 2015It is shown that given a metric space $X$ and a $\sigma$-finite positive regular Borel measure $\mu$ on $X$, there exists a bounded continuous real-valued function on $X$ that is one-to-one on the complement of a set of $\mu$ measure zero.
Exact form of the exponential Foldy-Wouthuysen transformation operator for an arbitrary-spin particleMay 31 2016Sep 03 2016The exact exponential Foldy-Wouthuysen transformation operator applicable for a particle with an arbitrary spin is derived. It can be successfully utilized for verifying any Foldy-Wouthuysen transformation method based on the exponential operator. When ... More
Electric Current Multipole Moments in Classical ElectrodynamicsFeb 16 2014The general theory for electric current multipoles appearing at the motion of magnetic dipoles and change in these values or orientation has been suggested. Static multipoles, including an anapole, have been studied in detail.
An H-Theorem for the Lattice Boltzmann Approach to HydrodynamicsAug 05 1998The lattice Boltzmann equation can be viewed as a discretization of the continuous Boltzmann equation. Because of this connection it has long been speculated that lattice Boltzmann algorithms might obey an H-theorem. In this letter we prove that usual ... More
Foldy-Wouthuysen transformation for relativistic particles in external fieldsApr 27 2004A method of Foldy-Wouthuysen transformation for relativistic spin-1/2 particles in external fields is proposed. It permits determination of the Hamilton operator in the Foldy-Wouthuysen representation with any accuracy. Interactions between a particle ... More
General classical and quantum-mechanical description of magnetic resonanceAug 04 2015A general theoretical description of the magnetic resonance is given. General formulas describing a behavior of all components of the polarization vector at the magnetic resonance are derived in the case of an arbitrary initial polarization. The equations ... More
Field of a moving locked charge as applied to beam-beam interactions in storage ringsJul 20 2015Nov 21 2015It is shown that the Lorentz transformation cannot in general be formally applied to potentials and fields of particles locked in a certain region. In particular, this property relates to nucleons in nuclei and to particles and nuclei in storage rings. ... More
Universal statistics of vortex tangle in three-dimensional wave chaosJul 18 2017The tangled nodal lines (wave vortices) in random, three-dimensional wavefields are studied as an exemplar of a fractal loop soup. Their statistics are a three-dimensional counterpart to the characteristic random behaviour of nodal domains in quantum ... More
Interpolation on JetsMar 21 1997We show that for any finite generic union of pairs $(x_i,L_i)_i$ where $x_i\in L_i$ is a point of the line $L_i$ in projective $n$-space, the divisors $m_ix_i$ on the $L_i$ have maximal rank with respect to homogeneous $d$ forms for all $d\geq 0$ and ... More
General properties of the Foldy-Wouthuysen transformation and applicability of the corrected original Foldy-Wouthuysen methodFeb 06 2016General properties of the Foldy-Wouthuysen transformation which is widely used in quantum mechanics and quantum chemistry are considered. Merits and demerits of the original Foldy-Wouthuysen transformation method are analyzed. While this method does not ... More
Hamilton Operator and the Semiclassical Limit for Scalar Particles in an Electromagnetic FieldOct 09 2008We successively apply the generalized Case-Foldy-Feshbach-Villars (CFFV) and the Foldy-Wouthuysen (FW) transformation to derive the Hamiltonian for relativistic scalar particles in an electromagnetic field. In contrast to the original transformation, ... More
Pick and Peak InterpolationDec 24 2016We show how Pick interpolation and interpolation on peak interpolation sets can be combined in an abstract uniform algebra setting. In particular as a special case, the Rudin-Carleson theorem can be combined with the classical Pick interpolation theorem ... More
"Lattice-Free" Simulations of Topological Defect FormationSep 29 1997Aug 04 1998We examine simulations of the formation of domain walls, cosmic strings, and monopoles on a cubic lattice, in which the topological defects are assumed to lie at the zeros of a piecewise constant 1, 2, or 3 component Gaussian random field, respectively. ... More
Cosmic String Formation from Correlated FieldsJan 30 1997We simulate the formation of cosmic strings at the zeros of a complex Gaussian field with a power spectrum $P(k) \propto k^n$, specifically addressing the issue of the fraction of length in infinite strings. We make two improvements over previous simulations: ... More
Chemical evolution of giant molecular clouds in simulations of galaxiesApr 04 2016May 11 2016We present an analysis of Giant Molecular Clouds (GMCs) within hydrodynamic simulations of isolated, low-mass (M* ~ 10^9 M_sol) disc galaxies. We study the evolution of molecular abundances and the implications for CO emission and the X_CO conversion ... More
Isospin Invariance and Generalized Bose Statistics applied to Low Energy $K^{+-}K^0$ and $π^{+-}π^0$ Space SymmetriesMar 01 1999The use of isospin invariance and Generalized Bose statistics shows that the Bose-Einstein correlation (BEC) of identical bosons seen in the $K^+K^+$ and $\pi^+ \pi^+$ systems can be extended to apply to $K^+ K^o$ and $\pi^+ \pi^o$ pairs when they are ... More
Prospects for three-body Higgs decays into extra light scalarsSep 26 2016Within models containing a very light scalar particle coupled to the 125 GeV Higgs boson, we present the first detailed study of Higgs decays into three of these light scalars. We determine model-independent conditions which the scalar sector after electroweak ... More
Topology of Gleason Parts in maximal ideal spaces with no analytic discsFeb 14 2019Feb 15 2019We strengthen, in various directions, the theorem of Garnett that every $\sigma$-compact, completely regular space $X$ occurs as a Gleason part for some uniform algebra. In particular, we show that the uniform algebra can always be chosen so that its ... More
Inhomogeneity-induced variance of cosmological parametersSep 19 2011Feb 18 2012Modern cosmology relies on the assumption of large-scale isotropy and homogeneity of the Universe. However, locally the Universe is inhomogeneous and anisotropic. So, how can local measurements (at the 100 Mpc scale) be used to determine global cosmological ... More
Measurement of B(Ds+ -->ell+ nu) and the Decay Constant fDs From 600/pb of e+e- Annihilation Data Near 4170 MeVJan 09 2009Mar 11 2009We examine e+e- --> Ds^-D_s^{*+} and Ds^{*-}Ds^{+} interactions at 4170 MeV using the CLEO-c detector in order to measure the decay constant fDs with good precision. Previously our measurements were substantially higher than the most precise lattice based ... More
Computation of Unconstrained Elastic Equilibria of Complete Möbius Bands and their StabilitySep 01 2015Aug 16 2016Determining the equilibrium configuration of an elastic M\"{o}bius band is a challenging problem. In recent years numerical results have been obtained by other investigators, employing first the Kirchhoff theory of rods and later the developable, ruled-surface ... More
On the Computation of Multivariate Scenario Sets for the Skew-t and Generalized Hyperbolic FamiliesFeb 04 2014We examine the problem of computing multivariate scenarios sets for skewed distributions. Our interest is motivated by the potential use of such sets in the "stress testing" of insurance companies and banks whose solvency is dependent on changes in a ... More
Statistical Mechanics of Kinks in (1+1)-DimensionsDec 09 1992We investigate the thermal equilibrium properties of kinks in a classical $\phi^4$ field theory in $1+1$ dimensions. The distribution function, kink density, and correlation function are determined from large scale simulations. A dilute gas description ... More
The Shape of a Möbius Strip via Elastic Rod Theory RevisitedJul 02 2014Aug 18 2016In 1993 Mahadevan and Keller used the Kirchhoff rod theory to predict the shape of a M\"obius band. Starting from the solution for a square cross-section (isotropic), they employ numerical continuation in the cross-sectional aspect ratio in order to approach ... More
Products of Farey graphs are totally geodesic in the pants graphJul 27 2013Jun 12 2014We show that for a surface S, the subgraph of the pants graph determined by fixing a collection of curves that cut S into pairs of pants, once-punctured tori, and four-times-punctured spheres is totally geodesic. The main theorem resolves a special case ... More
Veneziano Amplitude of Vasiliev TheoryFeb 12 2018Feb 16 2018We compute the four-point function of scalar operators in CFTs with weakly broken higher spin symmetry at arbitrary 't Hooft coupling. We use the known three-point functions in these theories, the Lorentzian OPE inversion formula and crossing to fix the ... More
Automating Deductive Verification for Weak-Memory ProgramsMar 18 2017Feb 19 2018Writing correct programs for weak memory models such as the C11 memory model is challenging because of the weak consistency guarantees these models provide. The first program logics for the verification of such programs have recently been proposed, but ... More
Powers of ideals and convergence of Green functions with colliding polesAug 14 2012Aug 21 2012Let us have a family of ideals of holomorphic functions vanishing at N distinct points of a complex manifold, all tending to a single point. As is known, convergence of the ideals does not guarantee the convergence of the pluricomplex Green functions ... More
Strict Fejér Monotonicity by Superiorization of Feasibility-Seeking Projection MethodsMay 28 2014We consider the superiorization methodology, which can be thought of as lying between feasibility-seeking and constrained minimization. It is not quite trying to solve the full fledged constrained minimization problem; rather, the task is to find a feasible ... More
Convergence and Perturbation Resilience of Dynamic String-Averaging Projection MethodsJun 01 2012We consider the convex feasibility problem (CFP) in Hilbert space and concentrate on the study of string-averaging projection (SAP) methods for the CFP, analyzing their convergence and their perturbation resilience. In the past, SAP methods were formulated ... More
Breakdown of scale-invariance in the coarsening of phase-separating binary fluidsOct 03 1997We present evidence, based on lattice Boltzmann simulations, to show that the coarsening of the domains in phase separating binary fluids is not a scale-invariant process. Moreover we emphasise that the pathway by which phase separation occurs depends ... More
A General Method for Constructing Essential Uniform AlgebrasDec 26 2015Mar 04 2018A general method for constructing essential uniform algebras with prescribed properties is presented. Using the method, the following examples are constructed: an essential, natural, regular uniform algebra on the closed unit disc; an essential, natural ... More
The Power of Neutrino Mass Sum Rules for Neutrinoless Double Beta Decay ExperimentsJul 10 2013Jul 31 2013Neutrino mass sum rules relate the three neutrino masses within generic classes of flavour models, leading to restrictions on the effective mass parameter measured in experiments on neutrinoless double beta decay as a function of the lightest neutrino ... More
The Fourier transform of order statistics with applications to Lorentz spacesNov 17 1993We present a formula for the Fourier transforms of order statistics in $\Bbb R^n$ showing that all these Fourier transforms are equal up to a constant multiple outside the coordinate planes in $\Bbb R^n.$ For $a_1\geq ... \geq a_n\ge0$ and $q>0,$ denote ... More
Lees-Edwards boundary conditions for lattice BoltzmannMar 09 2001Mar 13 2001Lees Edwards boundary conditions (LEbc) for Molecular Dynamics simulations are an extension of the well known periodic boundary conditions and allow the simulation of bulk systems in a simple shear flow. We show how the idea of LEbc can be implemented ... More
Electrostatic interactions across a charged lipid bilayerJul 27 2006We present theoretical work in which the degree of electrostatic coupling across a charged lipid bilayer in aqueous solution is analyzed on the basis of nonlinear Poisson-Boltzmann theory. In particular, we consider the electrostatic interaction of a ... More
Quantum theory of structured monochromatic lightOct 19 2017Applications that envisage utilizing the orbital angular momentum (OAM) at the single photon level assume that the OAM degrees of freedom that the photons inherit from the classical wave solutions are orthogonal. To test this critical assumption, we quantize ... More
Locally covariant quantum field theory with external sourcesFeb 11 2014Sep 18 2014We provide a detailed analysis of the classical and quantized theory of a multiplet of inhomogeneous Klein-Gordon fields, which couple to the spacetime metric and also to an external source term; thus the solutions form an affine space. Following the ... More
The number of graphs and a random graph with a given degree sequenceMar 01 2010Dec 02 2011We consider the set of all graphs on n labeled vertices with prescribed degrees D=(d_1, ..., d_n). For a wide class of tame degree sequences D we prove a computationally efficient asymptotic formula approximating the number of graphs within a relative ... More
Roughness effects in laminar pipe flowMay 29 2019The impact of wall roughness on fully developed laminar pipe flow is investigated numerically. The roughness is comprised of square bars of varying size and pitch. Results show that the inverse relation between the friction factor and the Reynolds number ... More
Quantum control landscape for a $Λ$-atom in the vicinity of second order trapsAug 17 2015We show that the second order traps in the control landscape for a three-level $\Lambda$-system found in our previous work {\it Phys. Rev. Lett.} {\bf 106}, 120402 (2011) are not local maxima: there exist directions in the space of controls in which the ... More
Polynomials for symmetric orbit closures in the flag varietyOct 27 2013Sep 30 2014In [Wyser-Yong '13] we introduced polynomial representatives of cohomology classes of orbit closures in the flag variety, for the symmetric pair $(GL_{p+q}, GL_p \times GL_q)$. We present analogous results for the remaining symmetric pairs of the form ... More
A simple scaling for the minimum instability time-scale of two widely spaced planetsMay 23 2013Long-term instability in multi-planet exosystems is a crucial consideration when confirming putative candidates, analyzing exoplanet populations, constraining the age of exosystems, and identifying the sources of white dwarf pollution. Two planets which ... More
Integrable Fredholm Operators and Dual Isomonodromic DeformationsJun 05 1997The Fredholm determinants of a special class of integral operators K supported on the union of m curve segments in the complex plane are shown to be the tau-functions of an isomonodromic family of meromorphic covariant derivative operators D_l. These ... More
A Fluctuating Lattice Boltzmann Method for the Diffusion EquationJun 24 2016We derive a fluctuating lattice Boltzmann method for the diffusion equation. The derivation removes several shortcomings of previous derivations for fluctuating lattice Boltzmann methods for hydrodynamic systems. The comparative simplicity of this diffusive ... More
Generalized Boosting Algorithms for Convex OptimizationMay 10 2011Feb 14 2012Boosting is a popular way to derive powerful learners from simpler hypothesis classes. Following previous work (Mason et al., 1999; Friedman, 2000) on general boosting frameworks, we analyze gradient-based descent algorithms for boosting with respect ... More
Polynomials for GL_p x GL_q orbit closures in the flag varietyAug 12 2013Mar 04 2014The subgroup K=GL_p x GL_q of GL_{p+q} acts on the (complex) flag variety GL_{p+q}/B with finitely many orbits. We introduce a family of polynomials that specializes to representatives for cohomology classes of the orbit closures in the Borel model. We ... More
Giant edge spin accumulation in a symmetric quantum well with two subbandsJan 29 2016We have studied the edge spin accumulation in a high mobility two-dimensional electron gas formed in a symmetric well with two subbands. This study is strongly motivated by the recent experiment of Hernandez et al. [Phys. Rev. B {\bf 88}, 161305(R) (2013)] ... More
Q-ball candidates for self-interacting dark matterJun 01 2001We show that non-topological solitons, known as Q-balls, are promising candidates for self-interacting dark matter. They can satisfy the cross-section requirements for a broad range of masses. Unlike previously considered examples, Q-balls can stick together ... More
Measurement of the Relative Branching Fraction of $Υ(4S)$ to Charged and Neutral B-Meson PairsJun 02 2000Jun 08 2000We analyze 9.7 x 10^6 B\bar{B}$ pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Y(4S) resonance. We measure the rates for B^0 -> J/psi K^{(*)0} and B^+ -> J/psi K^{(*)+} decays ... More
A Bayesian analysis of the 69 highest energy cosmic rays detected by the Pierre Auger ObservatoryJan 11 2016The origins of ultra-high energy cosmic rays (UHECRs) remain an open question. Several attempts have been made to cross-correlate the arrival directions of the UHECRs with catalogs of potential sources, but no definite conclusion has been reached. We ... More
Database of Parliamentary Speeches in Ireland, 1919-2013Aug 15 2017We present a database of parliamentary debates that contains the complete record of parliamentary speeches from D\'ail \'Eireann, the lower house and principal chamber of the Irish parliament, from 1919 to 2013. In addition, the database contains background ... More
Multivariate Archimedean copulas, $d$-monotone functions and $\ell_1$-norm symmetric distributionsAug 26 2009It is shown that a necessary and sufficient condition for an Archimedean copula generator to generate a $d$-dimensional copula is that the generator is a $d$-monotone function. The class of $d$-dimensional Archimedean copulas is shown to coincide with ... More
Maximum entropy Edgeworth estimates of the number of integer points in polytopesOct 13 2009Aug 06 2010Abstract: The number of points $x=(x_1 ,x_2 ,...x_n)$ that lie in an integer cube $C$ in $R^n$ and satisfy the constraints $\sum_j h_{ij}(x_j )=s_i ,1\le i\le d$ is approximated by an Edgeworth-corrected Gaussian formula based on the maximum entropy density ... More
The effects of metallicity, UV radiation and non-equilibrium chemistry in high-resolution simulations of galaxiesJun 29 2015Feb 09 2016We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of $10^{9} \, \rm{M}_{\odot}$. The models use a resolution of $750 \, \rm{M}_{\odot}$ per particle and include a treatment for the full non-equilibrium chemical evolution ... More
Combinatorial results on (1,2,1,2)-avoiding $GL(p,\mathbb{C}) \times GL(q,\mathbb{C})$-orbit closures on $GL(p+q, \mathbb{C})/B$Mar 03 2014Using recent results of the second author which explicitly identify the "$(1,2,1,2)$-avoiding" $GL(p,\mathbb{C}) \times GL(q,\mathbb{C})$-orbit closures on the flag manifold $GL(p+q,\mathbb{C})/B$ as certain Richardson varieties, we give combinatorial ... More
Low-temperature behavior of two-dimensional Gaussian Ising spin glassesFeb 02 2004We perform Monte Carlo simulations of large two-dimensional Gaussian Ising spin glasses down to very low temperatures $\beta=1/T=50$. Equilibration is ensured by using a cluster algorithm including Monte Carlo moves consisting of flipping fundamental ... More
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: higher-order correlations revealed by germ-grain Minkowski FunctionalsSep 27 2016We probe the higher-order clustering of the galaxies in the final data release (DR12) of the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (BOSS) using the method of germ-grain Minkowski Functionals (MFs). Our sample consists of 410,615 ... More
Topology of Gleason Parts in maximal ideal spaces with no analytic discsFeb 14 2019We strengthen, in various directions, the theorem of Garnett that every sigma-compact, completely regular space X occurs as a Gleason part for some uniform algebra. In particular, we show that the uniform algebra can always be chosen so that its maximal ... More
A Cantor set whose polynomial hull contains no analytic discsJan 10 2018Mar 01 2019A generalization of a result of Wermer concerning the existence of polynomial hulls without analytic discs is presented. As a consequence it is shown that there exists a Cantor set $X$ in ${\mathbb C}^3$ whose polynomial hull is strictly larger than $X$ ... More
Prospects for three-body Higgs boson decays into extra light scalarsSep 26 2016Mar 17 2017Within models containing a very light scalar particle coupled to the 125 GeV Higgs boson, we present the first detailed study of Higgs decays into three of these light scalars. We determine model-independent conditions which the scalar sector after electroweak ... More
An asymptotic formula for the number of non-negative integer matrices with prescribed row and column sumsOct 13 2009Apr 05 2010We count mxn non-negative integer matrices (contingency tables) with prescribed row and column sums (margins). For a wide class of smooth margins we establish a computationally efficient asymptotic formula approximating the number of matrices within a ... More
Topology of Gleason Parts in maximal ideal spaces with no analytic discsFeb 14 2019Mar 04 2019We strengthen, in various directions, the theorem of Garnett that every $\sigma$-compact, completely regular space $X$ occurs as a Gleason part for some uniform algebra. In particular, we show that the uniform algebra can always be chosen so that its ... More
A General Method for Constructing Essential Uniform AlgebrasDec 26 2015A general method for constructing essential uniform algebras with prescribed properties is presented. Using the method, the following examples are constructed: an essential, natural, regular uniform algebra on the closed unit disc; an essential, natural ... More
Effect of shear on droplets in a binary mixtureAug 18 1997In this article we use a lattice-Boltzmann simulation to examine the effects of shear flow on a equilibrium droplet in a phase separated binary mixture. We find that large drops break up as the shear is increased but small drops dissolve. We also show ... More
The Relationship Between Separation Logic and Implicit Dynamic FramesMar 30 2012Jul 29 2012Separation logic is a concise method for specifying programs that manipulate dynamically allocated storage. Partially inspired by separation logic, Implicit Dynamic Frames has recently been proposed, aiming at first-order tool support. In this paper, ... More
Optimizing coating performance for diffusion under cyclic moisture exposureMay 10 2017Fickian diffusion is often used to model moisture transport through barrier coatings, where the goal is to protect an underlying substrate from the onset of corrosion caused by buildup of water or other aggressive species. Such coatings are often exposed ... More
The Double Cover of the Icosahedral Symmetry Group and Quark Mass TexturesNov 22 2010Feb 08 2011We investigate the idea that the double cover of the rotational icosahedral symmetry group is the family symmetry group in the quark sector. The icosahedral (A5) group was previously proposed as a viable family symmetry group for the leptons. To incorporate ... More
Nonlinear Eigenmodes of a Polariton Harmonic OscillatorJan 28 2015We investigate theoretically the quantum oscillator-like states recently observed experimentally in polariton condensates (Nat. Phys. 8, 190 (2012)). We consider a complex Gross-Pitaevskii type model which includes the effects of self-interactions, and ... More
The collapse of cooperation in evolving gamesFeb 26 2014Apr 08 2014Game theory provides a quantitative framework for analyzing the behavior of rational agents. The Iterated Prisoner's Dilemma in particular has become a standard model for studying cooperation and cheating, with cooperation often emerging as a robust outcome ... More