Results for "David Zuñiga-Noël"

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Intrinsic Calibration of Depth Cameras for Mobile Robots using a Radial Laser ScannerJul 03 2019Depth cameras, typically in RGB-D configurations, are common devices in mobile robotic platforms given their appealing features: high frequency and resolution, low price and power requirements, among others. These sensors may come with significant, non-linear ... More
Automatic Multi-Sensor Extrinsic Calibration for Mobile RobotsJun 11 2019In order to fuse measurements from multiple sensors mounted on a mobile robot, it is needed to express them in a common reference system through their relative spatial transformations. In this paper, we present a method to estimate the full 6DoF extrinsic ... More
PL-SLAM: a Stereo SLAM System through the Combination of Points and Line SegmentsMay 26 2017Apr 09 2018Traditional approaches to stereo visual SLAM rely on point features to estimate the camera trajectory and build a map of the environment. In low-textured environments, though, it is often difficult to find a sufficient number of reliable point features ... More
Interactions between moderately close inclusions for the 2D Dirichlet-LaplacianFeb 25 2015Jun 29 2015This paper concerns the asymptotic expansion of the solution of the Dirichlet-Laplace problem in a domain with small inclusions. This problem is well understood for the Neumann condition in dimension greater than two or Dirichlet condition in dimension ... More
Numerical search of discontinuities in self-consistent potential energy surfacesDec 18 2011May 01 2012Potential energy surfaces calculated with self-consistent mean-field methods are a very powerful tool, since their solutions are, in theory, global minima of the non-constrained subspace. However, this minimization leads to an incertitude concerning the ... More
Lattice Boltzmann Method for Heterogeneous Multi-class Traffic FlowSep 27 2018The traffic modelling often keeps the mesoscopic scale in the theoretical sphere because the integro-differential nature of its equations. In the present work we suggest to use the lattice Boltzmann method to overcome these difficulties. In particular, ... More
Ground Energy of the Magnetic Laplacian in Polyhedral BodiesSep 20 2013Dec 04 2013The asymptotic behavior of the first eigenvalues of magnetic Laplacian operators with large magnetic fields and Neumann realization in polyhedral domains is characterized by a hierarchy of model problems. We investigate properties of the model problems ... More
Permeability through a perforated domain for the incompressible 2D Euler equationsJun 17 2013We investigate the influence of a perforated domain on the 2D Euler equations. Small inclusions of size $\varepsilon$ are uniformly distributed on the unit segment or a rectangle, and the fluid fills the exterior. These inclusions are at least separated ... More
Kinematic identification of young nearby moving groups from a sample of chromospherically active stars in the RAVE catalogSep 14 2018The purpose of this study is the identification of young ($1< age < 100$ Myr), nearby ($d \leqslant100$ pc) moving groups (YNMGs) through their kinematic signature. YNMGs could be the result of the recent dispersal of young embedded clusters, such that ... More
A Dirichlet problem for the Laplace operator in a domain with a small hole close to the boundaryDec 14 2016Sep 19 2017We take an open regular domain $\Omega$ in $\mathbb{R}^n$ with $n\ge 3$. We introduce a pair of positive parameters $\epsilon_1$ and $\epsilon_2$ and we set $\epsilon\equiv(\epsilon_1,\epsilon_2)$. Then we define the perforated domain $\Omega_\epsilon$ ... More
A Dirichlet problem for the Laplace operator in a domain with a small hole close to the boundaryDec 14 2016Oct 24 2017We study the Dirichlet problem in a domain with a small hole close to the boundary. To do so, for each pair $\boldsymbol\varepsilon = (\varepsilon_1, \varepsilon_2 )$ of positive parameters, we consider a perforated domain $\Omega_{\boldsymbol\varepsilon}$ ... More
Magnetic Laplacian in sharp three dimensional conesMay 12 2015Mar 23 2016The core result of this paper is an upper bound for the ground state energyof the magnetic Laplacian with constant magnetic field on cones that are contained in ahalf-space. This bound involves a weighted norm of the magnetic field related to momentson ... More
Statistical mechanics approach to the electric polarization and dielectric constant of band insulatorsMay 10 2016Jan 31 2017We develop a theory for the analytic computation of the free energy of band insulators in the presence of a uniform and constant electric field. The two key ingredients are a perturbation-like expression of the Wannier-Stark energy spectrum of electrons ... More
Geometric orbital susceptibility: quantum metric without Berry curvatureMay 04 2016Oct 21 2016The orbital magnetic susceptibility of an electron gas in a periodic potential depends not only on the zero field energy spectrum but also on the geometric structure of cell-periodic Bloch states which encodes interband effects. In addition to the Berry ... More
On the eigenvalues of Aharonov-Bohm operators with varying polesOct 04 2013We consider a magnetic operator of Aharonov-Bohm type with Dirichlet boundary conditions in a planar domain. We analyse the behavior of its eigenvalues as the singular pole moves in the domain. For any value of the circulation we prove that the k-th magnetic ... More
Nodal domains, spectral minimal partitions, and their relation to Aharonov-Bohm operatorsNov 02 2017This survey is a short version of a chapter written by the first two authors in the book [A. Henrot, editor. Shape optimization and spectral theory. Berlin: De Gruyter, 2017] (where more details and references are given) but we have decided here to put ... More
Incised-valley morphologies and sedimentary-fills within the inner shelf of the northern Bay of BiscayOct 14 2008This study is a first synthesis focused on incised-valleys located within the inner shelf of the Bay of Biscay. It is based on previously published results obtained during recent seismic surveys and coring campaigns. The morphology of the valleys appears ... More
Strategic tradeoffs in competitor dynamics on adaptive networksJul 15 2016Jul 02 2017Recent empirical work highlights the heterogeneity of social competitions such as political campaigns: proponents of some ideologies seek debate and conversation, others create echo chambers. While symmetric and static network structure is typically used ... More
Detection of vertical muons with the HAWC water Cherenkov detectors and its application to gamma/hadron discriminationAug 30 2017The HAWC observatory reconstructs atmospheric showers induced by very high-energy primary cosmic- or gamma-rays. Cosmic-rays with hadronic nature are several orders of magnitude more frequent than primary gammas and therefore it is necessary to perform ... More
Conductance in diffusive quasi-one-dimensional periodic waveguides: a semiclassical and random matrix studyJan 17 2012We study quantum transport properties of finite periodic quasi-one-dimensional waveguides whose classical dynamics is diffusive. The system we consider is a scattering configuration, composed of a finite periodic chain of $L$ identical (classically chaotic ... More
Dry granular flows: rheological measurements of the $μ(I)$-RheologyOct 31 2014May 21 2015Granular materials do not flow homogeneously like fluids when submitted to external stress,but often form rigid regions that are separated by narrow shear bands where the material yields and flows. This shear localization impacts their apparent rheology, ... More
Compact cold atom clock for on-board timebase: tests in reduced gravityDec 04 2018We present a compact atomic clock using cold rubidium atoms based on an isotropic light cooling, a Ramsey microwave interrogation and an absorption detection. Its technology readiness level is suitable to industrial transfer. We use a fibre optical bench, ... More
Cohomologie $L^{p}$ et formes harmoniquesJun 03 2010We show that a if a Riemannian manifold admits a universal cover with bounded geometry and if 0 does not belong to the spectrum or is an isolated point in the spectrum of the Laplacian on $\ell$-forms, then there exists $1<p<2$ such that for all $p<r<p^{\prime}$ ... More
Not a Technology Person: Motivating Older Adults Toward the Use of Mobile TechnologyJul 25 2017Older users population is rapidly increasing all over the World. Presently, we observe efforts in the human-computer interaction domain aiming to improve life quality of age 65 and over through the use of mobile apps. Nonetheless, these efforts focus ... More
Diffusive transport of waves in a periodic waveguideFeb 02 2011Jan 23 2012We study the propagation of waves in quasi-one-dimensional finite periodic systems whose classical (ray) dynamics is diffusive. By considering a random matrix model for a chain of $L$ identical chaotic cavities, we show that its average conductance as ... More
Patient-specific simulation of stent-graft deployment within an abdominal aortic aneurysmJan 15 2014In this study, finite element analysis is used to simulate the surgical deployment procedure of a bifurcated stent-graft on a real patient's arterial geometry. The stent-graft is modeled using realistic constitutive properties for both the stent and most ... More
Liquid-gas coexistence vs. energy minimization with respect to the density profile in the inhomogeneous inner crust of neutron starsMay 26 2015Jun 19 2015We compare two approaches to describe the inner crust of neutron stars: on the one hand, the simple coexistence of a liquid (clusters) and a gas phase, and on the other hand, the energy minimization with respect to the density profile, including Coulomb ... More
Collective Modes in a Superfluid Neutron Gas within the Quasiparticle Random-Phase ApproximationJun 02 2014Jan 05 2015We study collective excitations in a superfluid neutron gas at zero temperature within the quasiparticle random phase approximation. The particle-hole residual interaction is obtained from a Skyrme functional, while a separable interaction is used in ... More
Superfluid hydrodynamics in the inner crust of neutron starsJun 03 2016Nov 21 2016The inner crust of neutron stars is supposed to be inhomogeneous and composed of dense structures (clusters) that are immersed in a dilute gas of unbound neutrons. Here we consider spherical clusters forming a BCC crystal and cylindrical rods arranged ... More
Mechanical impulse propagation in a packing of 3D spheres confined at constant pressureNov 13 2015Mechanical impulse propagation in granular media depends strongly on the imposed confinement conditions. In this work, the propagation of sound in a granular packing contained by flexible walls that enable confinement under hydrostatic pressure conditions ... More
Superfluid hydrodynamics in the inner crust of neutron starsJun 03 2016Jul 28 2016The inner crust of neutron stars is supposed to be inhomogeneous and composed of dense structures (clusters) that are immersed in a dilute gas of unbound neutrons. Here we consider spherical clusters forming a BCC crystal and cylindrical rods arranged ... More
The nature of quasistatic deformation in granular materialsJan 15 2009Strain in granular materials in quasistatic conditions under varying stress originate in (I) contact deformation and (II) rearrangements of the contact network. Depending on sample history and applied load, either mechanism might dominate. One may thus ... More
On several two-boundary problems for a particular class of Lévy processesJan 31 2007Several two-boundary problems are solved for a special L\'{e}vy process: the Poisson process with an exponential component. The jumps of this process are controlled by a homogeneous Poisson process, the positive jump size distribution is arbitrary, while ... More
Stable Leader Election in Population Protocols Requires Linear TimeFeb 14 2015Aug 20 2016A population protocol *stably elects a leader* if, for all $n$, starting from an initial configuration with $n$ agents each in an identical state, with probability 1 it reaches a configuration $\mathbf{y}$ that is correct (exactly one agent is in a special ... More
Binary Survival in the Outer Solar SystemMay 06 2019As indicated by their special characteristics, the cold classical Kuiper belt objects (KBOs) formed and survived at 42-47 au. Notably, they show a large fraction of equal-size binaries whose formation is probably related to the accretion of KBOs themselves. ... More
Integrals derived from the doubling methodOct 21 2018In this note, we use a basic identity, derived from the generalized doubling integrals of \cite{C-F-G-K1}, in order to explain the existence of various global Rankin-Selberg integrals for certain $L$-functions. To derive these global integrals, we use ... More
How granular materials deform in quasistatic conditionsNov 10 2010Based on numerical simulations of quasistatic deformation of model granular materials, two rheological regimes are distinguished, according to whether macroscopic strains merely reflect microscopic material strains within the grains in their contact regions ... More
Elasticity of sphere packings: pressure and initial state dependenceJan 15 2009Elastic properties and internal states of isotropic sphere packings are studied by numerical simulations. Several numerical protocols to assemble dense configurations are compared. One, which imitates experiments with lubricated contacts, produces well ... More
A Performance Vocabulary for Affine Loop TransformationsNov 14 2018Apr 09 2019Modern polyhedral compilers excel at aggressively optimizing codes with static control parts, but the state-of-practice to find high-performance polyhedral transformations especially for different hardware targets still largely involves auto-tuning. In ... More
Nodal and spectral minimal partitions -- The state of the art in 2015 --Jun 24 2015In this article, we propose a state of the art concerning the nodal and spectral minimal partitions. First we focus on the nodal partitions and give some examples of Courant sharp cases. Then we are interested in minimal spectral partitions. Using the ... More
Optimal partitions for the sum and the maximum of eigenvaluesFeb 06 2017In this paper we compare the candidates to be spectral minimal partitions for two criteria: the maximum and the average of the first eigenvalue on each subdomains of the partition. We analyze in detail the square, the disk and the equilateral triangle. ... More
Grey-box state-space identification of nonlinear mechanical vibrationsApr 28 2018The present paper deals with the identification of nonlinear mechanical vibrations. A grey-box, or semi-physical, nonlinear state-space representation is introduced, expressing the nonlinear basis functions using a limited number of measured output variables. ... More
The Detection of Two Distinct High Ionization States in a QSO Lyman Limit Absorption System: Evidence for Hierarchical Galaxy Formation at z ~ 3?Jan 19 1999We have detected two high ionization phases of gas in the z ~ 2.77 partial Lyman limit system (LLS) towards QSO 1157-3143. We detect the first phase by CIV and SiIV absorption, and the second phase -- which is either warmer or undergoing larger random ... More
Continuum Percolation for Quermass ModelJan 11 2012The continuum percolation for Markov (or Gibbs) germ-grain models is investigated. The grains are assumed circular with random radii on a compact support. The morphological interaction is the so-called Quermass interaction defined by a linear combination ... More
Randomized greedy algorithms for independent sets and matchings in regular graphs: Exact results and finite girth correctionsJul 08 2008We derive new results for the performance of a simple greedy algorithm for finding large independent sets and matchings in constant degree regular graphs. We show that for $r$-regular graphs with $n$ nodes and girth at least $g$, the algorithm finds an ... More
Two Identities relating Eisenstein series on classical groupsAug 05 2018In this paper we introduce two general identities relating Eisenstein series on split classical groups, as well as double covers of symplectic groups. The first identity can be viewed as an extension of the doubling construction introduced in [CFGK17]. ... More
The transverse proximity effect in the z ~ 2 Lyman-alpha forest suggests QSO episodic lifetimes of ~1 MyrSep 12 2008We look for signs of the H~I transverse proximity effect in the spectra of 130 QSO pairs, most with transverse separations in the plane of the sky of 0.1 -- 3 Mpc at z ~ 2.2. We expected to see a decrease in Lyman-alpha forest HI absorption in the spectrum ... More
Comet Encounters and Carbon 14Nov 26 2012The $^{14}$C production of shock-accelerated particles is calculated in terms of the total energy released in energetic particles. The recently reported 1.2% jump in the $^{14}$C content of the atmosphere in the year C.E. 775, it is found, would require ... More
Perturbations for transient accelerationDec 22 2011Apr 24 2012According to the standard $\Lambda$CDM model, the accelerated expansion of the Universe will go on forever. Motivated by recent observational results, we explore the possibility of a finite phase of acceleration which asymptotically approaches another ... More
Simple inhomogeneous cosmological (toy) modelsFeb 27 2016Apr 07 2016Based on the Lema\^itre-Tolman-Bondi (LTB) metric we consider two flat inhomogeneous big-bang models. We aim at clarifying, as far as possible analytically, basic features of the dynamics of the simplest inhomogeneous models and to point out the potential ... More
Spontaneous parity breaking of graphene in the quantum Hall regimeJul 19 2006Nov 17 2006We propose that the inversion symmetry of the graphene honeycomb lattice is spontaneously broken via a magnetic field dependent Peierls distortion. This leads to valley splitting of the $n=0$ Landau level but not of the other Landau levels. Compared to ... More
Influences des paramètres micromécaniques dans la simulation numérique discrète des matériaux granulaires : assemblage, déformation quasi-statique, écoulementsNov 04 2010We review the influence of micromechanical parameters on the macroscopic mechanical behaviour of granular materials, as numerically simulated in discrete element approaches, both in quasistatic conditions an din dense flow. We insist in particular on ... More
Synthetic Lung Nodule 3D Image Generation Using AutoencodersNov 19 2018Dec 24 2018One of the challenges of using machine learning techniques with medical data is the frequent dearth of source image data on which to train. A representative example is automated lung cancer diagnosis, where nodule images need to be classified as suspicious ... More
Spectral minimal partitions for a family of toriMar 16 2015Apr 22 2016We study partitions of the rectangular two-dimensional flat torus of length 1 and width b into k domains, with b a parameter in (0, 1] and k an integer. We look for partitions which minimize the energy, definedas the largest first eigenvalue of the Dirichlet ... More
The RASNIK Real-Time Relative Alignment Monitor for the CDF Inner Tracking DetectorsDec 10 2002We describe the design and operation of the RASNIK optical relative alignment system designed for and installed on the CDF inner tracking detectors. The system provides low-cost minute-by-minute alignment monitoring with submicron precision. To reduce ... More
Site Disordered Spin Systems in the Gaussian Variational ApproximationJun 06 1996Dec 16 1996We define a replica field theory describing finite dimensional site disordered spin systems by introducing the notion of grand canonical disorder, where the number of spins in the system is random but quenched. A general analysis of this field theory ... More
Splitting cycles in graphsApr 26 2012The goal of this paper is to describe a sufficient condition on cycles in graphs for which the edge ideal is splittable. We give an explicit splitting function for such ideals.
Charge density wave in graphene: magnetic-field-induced Peierls instabilityDec 15 2006We suggest that a magnetic-field-induced Peierls instability accounts for the recent experiment of Zhang et al. in which unexpected quantum Hall plateaus were observed at high magnetic fields in graphene on a substrate. This Peierls instability leads ... More
Incremental response of granular materials: DEM resultsNov 03 2010We systematically investigate the incremental response of various equilibrium states of dense 2D model granular materials, along the biaxial compression path (\sigma 11 < \sigma 22, \sigma 12 = 0). Stress increments are applied in arbitrary directions ... More
Internal states of model isotropic granular packings. III. Elastic propertiesMay 22 2007Dec 18 2007In this third and final paper of a series, elastic properties of numerically simulated isotropic packings of spherical beads assembled by different procedures and subjected to a varying confining pressure P are investigated. In addition P, which determines ... More
Simulation nnnumérique discrète et comportement mécanique des matériaux granulairesJan 22 2009As a complementary tool to laboratory experiments, discrete numerical simulation, applied to granular materials, provides valuable information on the grain and contact scale microstructure, thereby enabling one to better understand the microscopic origin ... More
Superconductivity in domains with cornersFeb 15 2007We study the two-dimensional Ginzburg-Landau functional in a domain with corners for exterior magnetic field strengths near the critical field where the transition from the superconducting to the normal state occurs. We discuss and clarify the definition ... More
Magnetic Neumann Laplacian on a sharp coneSep 10 2013This paper is devoted to the spectral analysis of the Laplacian with constant magnetic field on a cone of aperture $\alpha$ and Neumann boundary condition. We analyze the influence of the orientation of the magnetic field. In particular, for any orientation ... More
Linear Corotation Torques in Non-Barotropic DisksOct 31 2013Jan 13 2014I derive a fully analytic expression for the linear corotation torque to first order in eccentricity for planets in non-barotropic protoplanetary disks, taking into account the effect of disk entropy gradients. This torque formula is applicable to both ... More
Protoplanetary Disk Resonances and Type I MigrationJul 20 2011Oct 03 2011Waves reflected by the inner edge of a protoplanetary disk are shown to significantly modify Type I migration, even allowing the trapping of planets near the inner disk edge for small planets in a range of disk parameters. This may inform the distribution ... More
Bounds for the Lang-Trotter conjecturesAug 31 2015For a non-CM elliptic curve $E$ defined over the rationals, Lang and Trotter made very deep conjectures concerning the number of primes $p\leq x$ for which $a_p(E)$ is a fixed integer (and for which the Frobenius field at $p$ is a fixed imaginary quadratic ... More
Efficient arithmetic on elliptic curves in characteristic 2Jan 14 2016We present normal forms for elliptic curves over a field of characteristic $2$ analogous to Edwards normal form, and determine bases of addition laws, which provide strikingly simple expressions for the group law. We deduce efficient algorithms for point ... More
Addition law structure of elliptic curvesMay 20 2010Jan 13 2011The study of alternative models for elliptic curves has found recent interest from cryptographic applications, once it was recognized that such models provide more efficiently computable algorithms for the group law than the standard Weierstrass model. ... More
Universal coefficients for overconvergent cohomology and the geometry of eigenvarietiesSep 04 2012Oct 01 2012We prove a universal coefficients theorem for the overconvergent cohomology modules introduced by Ash and Stevens, and give several applications. In particular, we sketch a very simple construction of eigenvarieties using overconvergent cohomology and ... More
The Petersson norm of the Jacobi theta functionOct 03 2011We compute the Petersson norm of the Jacobi theta function, by a simple application of the Rankin-Selberg method and a little trick.
A note on star-like configurations in finite settingsSep 05 2013Given $E \subset \mathbb{F}_q^d$, we show that certain configurations occur frequently when $E$ is of sufficiently large cardinality. Specifically, we show that we achieve the statistically number of $k$-stars $\displaystyle\left|\left\{(x, x^1, \dots, ... More
Vesicles in magnetic fieldsAug 19 2016Liposome vesicles tend to align with an applied magnetic field. This is due to the directional magnetic susceptibility difference of the lipids which form the membrane of these vesicles. In this work a model of liposome vesicles exposed to magnetic field ... More
An Axiomatic Framework for Belief UpdatesMar 27 2013In the 1940's, a physicist named Cox provided the first formal justification for the axioms of probability based on the subjective or Bayesian interpretation. He showed that if a measure of belief satisfies several fundamental properties, then the measure ... More
A Bayesian Approach to Learning Causal NetworksFeb 20 2013May 16 2015Whereas acausal Bayesian networks represent probabilistic independence, causal Bayesian networks represent causal relationships. In this paper, we examine Bayesian methods for learning both types of networks. Bayesian methods for learning acausal networks ... More
Causal Independence for Knowledge Acquisition and InferenceMar 06 2013May 16 2015I introduce a temporal belief-network representation of causal independence that a knowledge engineer can use to elicit probabilistic models. Like the current, atemporal belief-network representation of causal independence, the new representation makes ... More
Renormalized waves and thermalization of the Klein-Gordon equation: What sound does a nonlinear string make?Nov 04 2010Jun 30 2011We study the thermalization of the classical Klein-Gordon equation under a u^4 interaction. We numerically show that even in the presence of strong nonlinearities, the local thermodynamic equilibrium state exhibits a weakly nonlinear behavior in a renormalized ... More
A note on insufficiency and the preservation of Fisher informationJul 19 2011Apr 20 2012Kagan and Shepp (2005, Amer. Statist.) presented an elegant example of a mixture model for which an insufficient statistic preserves Fisher information. This note uses the regularity property of differentiability in quadratic mean to provide another explanation ... More
Multiple Landen values and the tribonacci numbersApr 21 2015Apr 24 2015Multiple Landen values (MLVs) are defined as iterated integrals on the interval $x\in[0,1]$ of the differential forms $A=d\log(x)$, $B=-d\log(1-x)$, $F=-d\log(1-\rho^2x)$ and $G=-d\log(1-\rho x)$, where $\rho=(\sqrt{5}-1)/2$ is the golden section. I conjecture ... More
On the growth of permutation classesJun 22 2015We study aspects of the enumeration of permutation classes, sets of permutations closed downwards under the subpermutation order. First, we consider monotone grid classes of permutations. We present procedures for calculating the generating function of ... More
Evolution of cosmological perturbations in a brane-universeOct 10 2000The present article analyses the impact on cosmology, in particular on the evolution of cosmological perturbations, of the existence of extra-dimensions. The model considered here is that of a five-dimensional Anti-de Sitter spacetime where ordinary matter ... More
Glimpses into the early UniverseOct 02 2009This contribution gives a brief overview of the theoretical ideas underlying our current understanding of the early Universe. Confronting the predictions of the early Universe models with cosmological observations, in particular of the cosmic microwave ... More
Superfluid neutron starsFeb 02 2001Neutron stars are believed to contain (neutron and proton) superfluids. I will give a summary of a macroscopic description of the interior of neutron stars, in a formulation which is general relativistic. I will also present recent results on the oscillations ... More
Cosmological CMBR dipole in open universes ?Jun 10 1997The observed CMBR dipole is generally interpreted as a Doppler effect arising from the motion of the Earth relative to the CMBR frame. An alternative interpretation, proposed in the last years, is that the dipole results from ultra-large scale isocurvature ... More
Control of pseudodifferential operators by maximal functions via weighted inequalitiesAug 23 2016We establish general weighted $L^2$ inequalities for pseudodifferential operators associated to the H\"ormander symbol classes $S^m_{\rho,\delta}$. Such inequalities provide optimal control of these operators by geometrically-defined maximal functions, ... More
Velocity Effects on the Deflection of Light by Gravitational MicrolensesOct 07 2004We study the influence of general lens and source velocities on the gravitational deflection of light by single and two-point-mass microlenses with general axis orientation. We demonstrate that in all cases the lens equation preserves its form exactly. ... More
Run II Searches for SupersymmetrySep 30 2004In these proceedings, we present all of the Run II results in the search for Supersymmetry from the Tevatron. At the time of presentation ~200 pb-1 of Run II data had been analyzed for the presence of new physics. We summarize searches for CHAMPS, Squarks ... More
Conformal Tensors via Lovelock GravityJun 19 2013Jun 24 2013Constructs from conformal geometry are important in low dimensional gravity models, while in higher dimensions the higher curvature interactions of Lovelock gravity are similarly prominent. Considering conformal invariance in the context of Lovelock gravity ... More
A Simple Spin Glass Perspective on Martensitic Shape-memory AlloysJan 15 2008Mar 04 2008A brief qualitative mapping is given between austenite, tweed and twinned phases of martensite alloys and corresponding paramagnetic, spin glass and periodic phases in spin glass alloys.
Understanding glassy phenomena in materialsJul 09 2010Oct 11 2010A basis for understanding and modelling glassy behaviour in martensitic alloys and relaxor ferroelectrics is discussed from the perspective of spin glasses.
The Minority Game: a statistical physics perspectiveDec 14 2005A brief review is given of the minority game, an idealized model stimulated by a market of speculative agents, and its complex many-body behaviour. Particular consideration is given to analytic results for the model rather than discussions of its relevance ... More
Strategies for The Determination of phi3 in B- -> D0 K-Mar 30 2001Direct CP violation in decays such as B- -> D0 K- is sensitive to the CKM angle phi_3 because these decays allow the interference of b-quark to c-quark with b-quark to u-quark transitions. Indeed, phi_3 may be determined if one can infer the strong phase ... More
A Direct Proof of BCFW Recursion for Twistor-StringsJul 01 2010This paper gives a direct proof that the leading trace part of the genus zero twistor-string path integral obeys the BCFW recursion relation. This is the first complete proof that the twistor-string correctly computes all tree amplitudes in maximally ... More
Internally heated convection beneath a poor conductorJun 29 2016We consider convection in an internally heated layer of fluid that is bounded below by a perfect insulator and above by a poor conductor. The poorly conducting boundary is modelled by a fixed heat flux. Using solely analytical methods, we find linear ... More
A Quantum Hall Fluid of VorticesJun 26 2003Jul 03 2003In this note we demonstrate that vortices in a non-relativistic Chern-Simons theory form a quantum Hall fluid. We show that the vortex dynamics is controlled by the matrix mechanics previously proposed by Polychronakos as a description of the quantum ... More
The Moduli Space of BPS Domain WallsFeb 01 2002Apr 25 2002N=2 SQED with several flavors admits multiple, static BPS domain wall solutions. We determine the explicit two-kink metric and examine the dynamics of colliding domain walls. The multi-kink metric has a toric Kahler structure and we reduce the Kahler ... More
Superconformal Vortex StringsOct 19 2006Nov 27 2006We study the low-energy dynamics of semi-classical vortex strings living above Argyres-Douglas superconformal field theories. The worldsheet theory of the string is shown to be a deformation of the CP^N model which flows in the infra-red to a superconformal ... More
Classicality of quantum information processingAug 22 2001May 01 2002The ultimate goal of the classicality programme is to quantify the amount of quantumness of certain processes. Here, classicality is studied for a restricted type of process: quantum information processing (QIP). Under special conditions, one can force ... More
Constructing local L-packets for tame unitary groupsNov 29 2013We generalize the work of DeBacker and Reeder to the case of unitary groups split by a tame extension. The approach is broadly similar and the restrictions on the parameter the same, but many of the details of the arguments differ. Let $G$ be a unitary ... More
Developing and Analyzing Boundary Detection Operators Using Probabilistic ModelsMar 27 2013Most feature detectors such as edge detectors or circle finders are statistical, in the sense that they decide at each point in an image about the presence of a feature, this paper describes the use of Bayesian feature detectors.
Graphs with few paths of prescribed length between any two verticesNov 04 2014We use a variant of Bukh's random algebraic method to show that for every natural number $k \geq 2$ there exists a natural number $\ell$ such that, for every $n$, there is a graph with $n$ vertices and $\Omega_k(n^{1 + 1/k})$ edges with at most $\ell$ ... More