Results for "Eric Evert"

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Matrix Convex Sets Without Absolute Extreme PointsAug 07 2017This article shows the existence of a class of closed bounded matrix convex sets which do not have absolute extreme points. The sets we consider are noncommutative sets, $K_X$, formed by taking matrix convex combinations of a single tuple $X$. In the ... More
The noncommutative Waring problemMar 14 2019This paper poses and treats a noncommutative version of the classical Waring problem for polynomials. That is, for a homogeneous \nc \ polynomial $p$, we find a condition equivalent to $p$ being expressible as sums of powers of homogeneous \nc \ polynomials. ... More
Arveson extreme points span free spectrahedraJun 23 2018Let $ SM_n(\mathbb{R})^g$ denote $g$-tuples of $n \times n$ real symmetric matrices. Given tuples $X=(X_1, \dots, X_g) \in SM_{n_1}(\mathbb{R})^g$ and $Y=(Y_1, \dots, Y_g) \in SM_{n_2}(\mathbb{R})^g$, a matrix convex combination of $X$ and $Y$ is a sum ... More
Circular Free SpectrahedraApr 19 2016This paper considers matrix convex sets invariant under several types of rotations. It is known that matrix convex sets that are free semialgebraic are solution sets of Linear Matrix Inequalities (LMIs); they are called free spectrahedra. We classify ... More
Extreme points of matrix convex sets, free spectrahedra and dilation theoryNov 30 2016For matrix convex sets a unified geometric interpretation of notions of extreme points and of Arveson boundary points is given. These notions include, in increasing order of strength, the core notions of "Euclidean" extreme points, "matrix" extreme points, ... More
Factor posets of frames and dual frames in finite dimensionsNov 15 2014We consider frames in a finite-dimensional Hilbert space where frames are exactly the spanning sets of the vector space. A factor poset of a frame is defined to be a collection of subsets of $I$, the index set of our vectors, ordered by inclusion so that ... More
Multiple Populations in Globular Clusters: The Possible Contributions of Stellar CollisionsApr 23 2010Globular clusters were thought to be simple stellar populations, but recent photometric and spectroscopic evidence suggests that the clusters' early formation history was more complicated. In particular, clusters show star-to-star abundance variations, ... More
Consensus problems with arbitrary sign-preserving nonlinearitiesAug 09 2015May 13 2017This paper studies consensus problems for multi-agent systems defined on directed graphs where the consensus dynamics involves nonlinear and discontinuous functions. Sufficient conditions, involving the nonlinear functions and the topology of the underlying ... More
Dynamics of many-body localization in the presence of particle lossJun 02 2017At long times residual couplings to the environment become relevant even in the most isolated experiments, creating a crucial difficulty for the study of fundamental aspects of many-body dynamics. A particular example is many-body localization in a cold-atom ... More
Correlations in the Ising antiferromagnet on the anisotropic kagome latticeJul 07 2011Sep 16 2011We study the correlation function of middle spins, i. e. of spins on intermediate sites between two adjacent parallel lattice axes, of the spatially anisotropic Ising antiferromagnet on the kagome lattice. It is given rigorously by a Toeplitz determinant. ... More
Molybdenum-Rhenium alloy based high-$Q$ superconducting microwave resonatorsNov 18 2014Superconducting microwave resonators (SMR) with high quality factors have become an important technology in a wide range of applications. Molybdenum-Rhenium (MoRe) is a disordered superconducting alloy with a noble surface chemistry and a relatively high ... More
Asymptotically hyperbolic normalized Ricci flow and rotational symmetryJun 22 2015Sep 27 2016We consider the normalized Ricci flow evolving from an initial metric which is conformally compactifiable and asymptotically hyperbolic. We show that there is a unique evolving metric which remains in this class, and that the flow exists up to the time ... More
Asymptotically hyperbolic normalized Ricci flow and rotational symmetryJun 22 2015Dec 05 2018We consider the normalized Ricci flow evolving from an initial metric which is conformally compactifiable and asymptotically hyperbolic. We show that there is a unique evolving metric which remains in this class, and that the flow exists up to the time ... More
Window To The StarsJul 27 2006We present Window To The Stars, a graphical user interface to the popular TWIN single/binary stellar evolution code, for novices, students and professional astrophysicists. It removes the drudgery associated with the traditional approach to running the ... More
Thermohaline mixing and gravitational settling in carbon-enhanced metal-poor starsJul 10 2008We investigate the formation of carbon-enhanced metal-poor (CEMP) stars via the scenario of mass transfer from a carbon-rich asymptotic giant branch (AGB) primary to a low-mass companion in a binary system. We explore the extent to which material accreted ... More
Geometry induced pair condensationOct 09 2013We study a one-dimensional model of interacting bosons on a lattice with two flat bands. Regular condensation is suppressed due to the absence of a well defined minimum in the single particle spectrum. We find that interactions stabilize a number of non-trivial ... More
Realizations of Bialgebras (II) : Duality TheoremFeb 04 2005Feb 22 2005From the method of realization of bialgebras developped in a preceding paper, we obtain the Duality Theorem and apply it to the study of the ideal of relations for each realized bialgebra. This is detailed in the english version of the abstract of this ... More
Density-matrix renormalization group methods for momentum- and frequency-resolved dynamical correlation functionsAug 19 2008Several density-matrix renormalization group methods have been proposed to compute the momentum- and frequency-resolved dynamical correlation functions of low-dimensional strongly correlated systems. The most relevant approaches are discussed in this ... More
Identification of significant features in DNA microarray dataApr 13 2013DNA microarrays are a relatively new technology that can simultaneously measure the expression level of thousands of genes. They have become an important tool for a wide variety of biological experiments. One of the most common goals of DNA microarray ... More
Construction of initial data for 3+1 numerical relativityApr 02 2007Nov 07 2007This lecture is devoted to the problem of computing initial data for the Cauchy problem of 3+1 general relativity. The main task is to solve the constraint equations. The conformal technique, introduced by Lichnerowicz and enhanced by York, is presented. ... More
Generalized Representation Stability and FI_d-modulesJun 08 2016Jun 09 2016In this note we consider the complex representation theory of FI_d, a natural generalization of the category FI of finite sets and injections. We prove that finitely generated FI_d-modules exhibit behaviors in the spirit of Church-Farb representation ... More
Hawking Radiation from a Reisner-Nordström Domain WallSep 30 2009Dec 14 2009We investigate the effect on the Hawking radiation given off during the time of collapse of a Reisner-Nordstr\"om domain wall. Using the functional Schr\"odinger formalism we are able to probe the time-dependent regime, which is out of the reach of the ... More
Local Transformations Requiring Infinite Rounds of Classical CommunicationMay 17 2011In this paper, we study the number of rounds of communication needed to implement certain tasks by local quantum operations and classical communication (LOCC). We find that the class of LOCC operations becomes strictly more powerful as more rounds of ... More
Duality Symmetries and the Type II String Effective ActionSep 26 1995We discuss the duality symmetries of Type II string effective actions in nine, ten and eleven dimensions. As a by-product we give a covariant action underlying the ten--dimensional Type IIB supergravity theory. We apply duality symmetries to construct ... More
Summary of CP Violation in D -> hh Decays at BelleJan 20 2013Although CP violation is predicted to be small in the Standard Model, there exists a continuing theoretical interest within the charm sector due to enhancements of CPV through new physics processes. We present an overview of the measurements of direct ... More
Bar-driven fueling of galactic nuclei: a 2D viewSep 27 2004I discuss evidences for bar-driven gas fueling in the central regions of galaxies, focusing on scales down to about 10 pc. I thus mention the building of inner disks, and the link with resonances, as well as the corresponding kinematic signatures such ... More
Integral Field Spectrographs: a user's viewSep 25 2007We easily tend to think of Integral-Field Spectrographs (IFS) along two opposing trends: as either the beautiful combination between photometry and spectroscopy, or as our worst nightmare including the dark side of both worlds. I favour a view where each ... More
Secular evolution in the central regions of galaxiesSep 10 2001In this paper, I mention a few processes which may play a role in the evolution of the central regions of galaxies. In this context, I briefly discuss some issues regarding the formation of bulges in spirals, the role of supermassive black holes, and ... More
Discrete Torsion, Quotient Stacks, and String OrbifoldsOct 15 2001This is the writeup of a lecture given at the May Wisconsin workshop on mathematical aspects of orbifold string theory. In the first part of this lecture, we review recent work on discrete torsion, and outline how it is currently understood in terms of ... More
Seidel's Mirror Map for the TorusJun 17 2005Jul 25 2005Using only the Fukaya category and the monodromy around large complex structure, we reconstruct the mirror map in the case of a symplectic torus. This realizes an idea described by Paul Seidel.
What Transcription Factors Can't Do: On the Combinatorial Limits of Gene Regulatory NetworksDec 19 2013Jan 27 2014A proof is presented that gene regulatory networks (GRNs) based solely on transcription factors cannot control the development of complex multicellular life. GRNs alone cannot explain the evolution of multicellular life in the Cambrian Explosion. Networks ... More
On the complexity of learning a language: An improvement of Block's algorithmDec 11 2012Language learning is thought to be a highly complex process. One of the hurdles in learning a language is to learn the rules of syntax of the language. Rules of syntax are often ordered in that before one rule can applied one must apply another. It has ... More
Hierarchical Bayesian estimation of inequality measures with nonrectangular censored survey data with an application to wealth distribution of French householdsJul 29 2011We consider the estimation of wealth inequality measures with their confidence interval, based on survey data with interval censoring. We rely on a Bayesian hierarchical model. It consists of a model where, due to survey sampling and unit nonresponse, ... More
Deeply Virtual Compton Scattering at JLab Hall ASep 27 2007The deeply virtual Compton scattering reaction has been investigated in the Hall A of the Jefferson Laboratory by measuring longitudinally polarized (e,e'gamma) cross sections, in the valence quark region, for protons and neutrons. In the proton channel, ... More
Meunier ConjectureSep 01 2012Fr\'ed\'eric Meunier's question about a multicolored Sperner lemma is addressed, leaving the question of connectivity for the color hypergraphs of such a multicolored simplex. Sperner's lemma asserts the existence of a simplex using all the colors for ... More
Color superconductivity in the Nambu Jona-Lasinio model complemented by a Polyakov loopJun 08 2016The color superconductivity was studied with an adaptation of the Nambu and Jona-Lasinio model (NJL). This one was coupled to a Polyakov loop, to form the PNJL model. A $\mu$-dependent Polyakov loop potential was considered. An objective of the presented ... More
Quantum Collapse of a Charged $n$-dimensional BTZ-like Domain WallMay 20 2016We investigate both the classical and quantum gravitational collapse of a charged, non-rotating $n$-dimensional BTZ black hole in AdS space. This is done by first deriving the conserved mass of a "spherically" symmetric domain wall, which is then taken ... More
Bounding the Space of Holographic CFTs with ChaosFeb 26 2016Oct 14 2016Thermal states of quantum systems with many degrees of freedom are subject to a bound on the rate of onset of chaos, including a bound on the Lyapunov exponent, $\lambda_L\leq 2\pi /\beta$. We harness this bound to constrain the space of putative holographic ... More
Closed subgroups of the polynomial automorphism group containing the affine subgroupSep 09 2016We prove that, in characteristic zero, closed subgroups of the polynomial automorphisms group containing the affine group contain the whole tame group.
The rigid Horowitz-Myers conjectureFeb 19 2016The "new positive energy conjecture" Horowitz and Myers (1999) probes a possible nonsupersymmetric AdS/CFT correspondence. We consider a version formulated for complete, asymptotically Poincar\'e-Einstein Riemannian metrics $(M,g)$ with bounded scalar ... More
Theoretical approaches to the statistical physics of interacting non-conservative unitsAug 30 2016The aim of this review is to provide a concise overview of some of the generic approaches that have been developed to deal with the statistical description of large systems of interacting non-conservative 'units'. The latter notion includes, e.g., inelastic ... More
On the Oscillations of Second Order Linear Differential EquationsNov 09 2016This paper extends the discriminant associated to second order linear constant coefficient differential equations to general second order linear differential equations. The main result of this paper is that the discriminant of a second order linear differential ... More
On the covering number of symmetric groups of even degreeOct 28 2014Feb 03 2016If a group $G$ is the union of proper subgroups $H_1, \dots, H_k$, we say that the collection $\{H_1, \dots H_k \}$ is a cover of $G$, and the size of a minimal cover (supposing one exists) is the covering number of $G$, denoted $\sigma(G)$. Mar\'oti ... More
The Morava E-theory of Eilenberg-Mac Lane spacesSep 27 2011Sep 29 2011We deform the Ravenel-Wilson computation of the Morava K-homology of Eilenberg-Mac Lane spaces to obtain a similar description of their completed Morava E-homology. This yields both a cohomological description and an interpretation on the level of formal ... More
Stability phenomena in the homology of tree braid groupsSep 19 2016For a tree $G$, we study the changing behaviors in the homology groups $H_i(B_nG)$ as $n$ varies, where $B_nG := \pi_1($UConf$_n(G))$. We prove that the ranks of these homologies can be described by a single polynomial for all $n$, and construct this ... More
On the Shuffling Algorithm for Domino TilingsFeb 19 2008We study the dynamics of a certain discrete model of interacting particles that comes from the so called shuffling algorithm for sampling a random tiling of an Aztec diamond. It turns out that the transition probabilities have a particularly convenient ... More
Milne-like Spacetimes and their SymmetriesMar 01 2018May 03 2018When developing a quantum theory for a physical system, one determines the system's symmetry group and its irreducible unitary representations. For Minkowski space, the symmetry group is the Poincar\'e group, $\mathbb{R}^4 \rtimes \text{O}(1,3)$, and ... More
Milne-like spacetimes and their role in CosmologyJun 05 2017May 04 2018Milne-like spacetimes are a class of FLRW models which admit $C^0$ spacetime extensions through the big bang. The boundary of a Milne-like spacetime can be identified with a null cone in the extension. We find that the comoving observers all emanate from ... More
Etude d'equations differentielles singulierement perturbees au voisinage d'un point tournantFeb 09 2001Consider a singularly perturbed ordinary differential equation, admitting 0 as turning point of order p. We study the behaviour, in the complex plane, of the solutions of this equation in the neighborhood of 0. We prove that the domain of these solutions ... More
Teaching practices of graduate teaching assistantsFeb 24 2016Physics education research has consistently shown that students have higher learning outcomes when enrolled in interactive-engagement courses. Consequently, many schools are actively reforming their introductory curricula. For courses where the interactive ... More
Order 1 strongly minimal sets in differentially closed fieldsOct 11 2005Jan 19 2007We give a classification of non-orthogonality classes of trivial order 1 strongly minimal sets in differentially closed fields. A central idea is the introduction of $\tau$-forms, functions on the prolongation of a variety which are analogous to 1-forms. ... More
Linear compactness and combinatorial bialgebrasSep 29 2018We present an expository overview of the monoidal structures in the category of linearly compact vector spaces. Bimonoids in this category are the natural duals of infinite-dimensional bialgebras. We classify the relations on words whose equivalence classes ... More
A few properties of sample varianceSep 11 2018A basic result is that the sample variance for i.i.d. observations is an unbiased estimator of the variance of the underlying distribution (see for instance Casella and Berger (2002)). But what happens if the observations are neither independent nor identically ... More
Measurement Errors as Bad Leverage PointsJul 08 2018Errors-in-variables is a long-standing, difficult issue in linear regression; and progress depends in part on new identifying assumptions. I characterize measurement error as bad-leverage points and assume that fewer than half the sample observations ... More
Quantifying the Loss of Information from Binning List-Mode DataFeb 12 2019List-mode data is increasingly being uesd in SPECT and PET imaging, among other imaging modalities. However, there are still many imaging designs that effectively bin list-mode data before image reconstruction or other estimation tasks are performed. ... More
Solutions of the $\bar \partial $-equation on Kähler manifold with compact supportFeb 07 2019We study the $\bar \partial $-equation in complete K\"ahler manifolds. The aim is to get $L^{r}$ and Sobolev estimates on solutions with compact support. We prove and use estimates on solutions on Poisson equation with compact support and the link with ... More
The Relation Between Bayesian Fisher Information and Shannon Information for Detecting a Change in a ParameterJan 31 2019We derive a connection between performance of estimators the performance of the ideal observer on related detection tasks. Specifically we show how Shannon Information for the task of detecting a change in a parameter is related to the Fisher Information ... More
Sobolev solutions of parabolic equation in a complete riemannian manifoldDec 11 2018Jan 03 2019We study Sobolev estimates for the solutions of parabolic equations acting on a vector bundle, in a complete riemannian manifold $M.$ The idea is to use known estimates in ${\mathbb{R}}^{n}$ to get local estimates on $M$ and then to use our LIR method ... More
On the dual nature of partial theta functions and Appell-Lerch sumsAug 30 2012Jul 14 2014In recent work, Hickerson and the author demonstrated that it is useful to think of Appell--Lerch sums as partial theta functions. This notion can be used to relate identities involving partial theta functions with identities involving Appell--Lerch sums. ... More
Cosets, genericity, and the Weyl groupJan 15 2008Sep 12 2008We prove a non-generosity theorem for proper cosets in groups of finite Morley rank and elaborate on the theory of Weyl groups in this context.
Intrinsic characterization for Lipschitz asymptotically hyperbolic metricsNov 21 2007Jul 11 2008Conformally compact asymptotically hyperbolic metrics have been intensively studied. The goal of this note is to understand what intrinsic conditions on a complete Riemannian manifold (M,g) will ensure that g is asymptotically hyperbolic in this sense. ... More
Graphical Condensation Generalizations Involving Pfaffians and DeterminantsMay 05 2006Graphical condensation is a technique used to prove combinatorial identities among numbers of perfect matchings of plane graphs. Propp and Kuo first applied this technique to prove identities for bipartite graphs. Yan, Yeh, and Zhang later applied graphical ... More
Tropical Intersection Theory from Toric VarietiesJul 15 2009We apply ideas from intersection theory on toric varieties to tropical intersection theory. We introduce mixed Minkowski weights on toric varieties which interpolate between equivariant and ordinary Chow cohomology classes on complete toric varieties. ... More
Critical Behaviour of the Partner ModelDec 10 2014Jul 18 2015We consider a stochastic model of infection spread incorporating monogamous partnership dynamics. In previous work a basic reproduction number $R_0$ is defined with the property that if $R_0<1$ the infection dies out within $O(\log N)$ units of time, ... More
New Results for the Two-Stage Contact ProcessJan 11 2014Here we continue the work started by Steve Krone on the two-stage contact process. We give a simplified proof of the duality relation, and answer most of the open questions posed in that paper. We also fill in the details of an incomplete proof.
A method of realization of bialgebras, and Hopf algebras associated to some realizationsDec 19 2003This article introduces a method, which starting from simple and quite general mathematical data, allows to construct linear algebras of operators which are, each of them, endowed with a bialgebra structure (coproduct and counity). Moreover under some ... More
Potential for Quantum-Mechanical Tests Using Quasars, as Illuminated by Gemini Archival DataSep 21 2018There has been recent interest in quantum-mechanical tests aided by distant quasars. For two quasars of sufficient redshift at opposite directions on the sky, light-travel-time arguments can assure the acausality of their photons. And if those photons ... More
A Tropical ToolkitOct 28 2006Apr 04 2008We give an introduction to Tropical Geometry and prove some results in Tropical Intersection Theory. The first part of this paper is an introduction to tropical geometry aimed at researchers in Algebraic Geometry from the point of view of degenerations ... More
Bifurcation delay - the case of the sequence: stable focus - unstable focus - unstable nodeJan 19 2009Let us give a two dimensional family of real vector fields. We suppose that there exists a stationary point where the linearized vector field has successively a stable focus, an unstable focus and an unstable node. When the parameter moves slowly, a bifurcation ... More
Quenched large deviations for interacting diffusions in random mediaAug 23 2016The aim of the paper is to establish a large deviation principle (LDP) for the empirical measure of mean-field interacting diffusions in a random environment. The point is to derive such a result once the environment has been frozen (quenched model). ... More
Noncyclic Division Algebras over Fields of Brauer Dimension OneMar 21 2019Let $K$ be a complete discretely valued field of rank one, with residue field $\Q_p$. It is well known that period equals index in $\Br(K)$. We prove that when $p=2$ there exist noncyclic $K$-division algebras of every $2$-power degree divisible by four. ... More
Time Evolution of Entropy in Gravitational CollapseNov 05 2008Apr 29 2009We study the time evolution of the entropy of a collapsing spherical domain wall, from the point of view of an asymptotic observer, by investigating the entropy of the entire system (i.e. domain wall and radiation) and induced radiation alone during the ... More
Galilean-Invariant XEFTMar 16 2015XEFT is a low-energy effective field theory for charm mesons and pions that provides a systematically improvable description of the X(3872) resonance. A Galilean-invariant formulation of XEFT is introduced to exploit the fact that mass is very nearly ... More
On three third order mock theta functions and Hecke-type double sumsAug 07 2012We obtain four Hecke-type double sums for three of Ramanujan's third order mock theta functions. We discuss how these four are related to the new mock theta functions of Andrews' work on $q$-orthogonal polynomials and Bringmann, Hikami, and Lovejoy's ... More
Combinatorial methods of character enumeration for the unitriangular groupDec 10 2010Jul 22 2011Let $\UT_n(q)$ denote the group of unipotent $n\times n$ upper triangular matrices over a field with $q$ elements. The degrees of the complex irreducible characters of $\UT_n(q)$ are precisely the integers $q^e$ with $0\leq e\leq \lfloor \frac{n}{2} \rfloor ... More
Laboratory Experiments on Wave TurbulenceJan 05 2010This review paper is devoted to a presentation of recent progress in wave turbulence. I first present the context and state of the art of this field of research both experimentally and theoretically. I then focus on the case of wave turbulence on the ... More
Bacterial hydrodynamicsSep 07 2015Bacteria predate plants and animals by billions of years. Today, they are the world's smallest cells yet they represent the bulk of the world's biomass, and the main reservoir of nutrients for higher organisms. Most bacteria can move on their own, and ... More
Life around the scallop theoremNov 12 2010Locomotion on small scales is dominated by the effects of viscous forces and, as a result, is subject to strong physical and mathematical constraints. Following Purcell's statement of the scallop theorem which delimitates the types of swimmer designs ... More
Life at high Deborah numberApr 28 2009In many biological systems, microorganisms swim through complex polymeric fluids, and usually deform the medium at a rate faster than the inverse fluid relaxation time. We address the basic properties of such life at high Deborah number analytically by ... More
Mathematical Properties of Dynamic Systems and the Foundations of Quantum TheoryJun 11 2011Oct 18 2016While it is widely acknowledged that quantum theory is strange, and that the world view it implies is elusive, there is considerably less consensus as to why this is the case. This article will explore the possibility that the theory is opaque because ... More
Relating F-Signature and F-Splitting Ratio of Pairs Using Left-DerivativesJun 19 2012Nov 27 2012We first relate an approximate $n^{th}$-order left derivative of $s(R, f^t)$ at the F-pure threshold $c$ to the F-splitting ratio $r_F(R, f^c)$. Next, we apply the methods developed by Monsky and Teixeira in their investigation of syzygy gaps and $p$-fractals ... More
Upper oriented chromatic number of undirected graphs and oriented colorings of product graphsMay 17 2010The oriented chromatic number of an oriented graph $\vec G$ is the minimum order of an oriented graph $\vev H$ such that $\vec G$ admits a homomorphism to $\vev H$. The oriented chromatic number of an undirected graph $G$ is then the greatest oriented ... More
On-off intermittency over an extended range of control parameterDec 01 2011Apr 23 2012We propose a simple phenomenological model exhibiting on-off intermittency over an extended range of control parameter. We find that the distribution of the 'off' periods has as a power-law tail with an exponent varying continuously between -1 and -2, ... More
Real space analysis of inherent structuresOct 21 2004Jul 26 2005We study a generalization of the one-dimensional disordered Potts model, which exhibits glassy properties at low temperature. The real space properties of inherent structures visited dynamically are analyzed through a decomposition into domains over which ... More
An exactly solvable dissipative transport modelSep 28 2005Feb 01 2006We introduce a class of one-dimensional lattice models in which a quantity, that may be thought of as an energy, is either transported from one site to a neighbouring one, or locally dissipated. Transport is controlled by a continuous bias parameter q, ... More
Inner density waves: The need for two-dimensional spectroscopyFeb 28 2002In this paper, I emphasize the need for integral field spectroscopy in the study of density waves (bars, spirals, m=1 modes) in the centre of galaxies. I illustrate this by focusing on the complex and time dependent structures revealed by such techniques. ... More
Is the black hole in NGC1277 really over-massive?May 15 2013A claim has been made by van den Bosch et al. (2012) that NGC1277 hosts an over-massive BH with a mass larger than half its spheroid mass. We revisit this claim by examining the predictions from dynamical realisations based on new MGE models of NGC1277. ... More
Extragalactic science at very high spectral resolutionSep 27 2004I briefly mention a few possible applications of very high spectral resolution spectroscopy with CRIRES to the study of nearby galaxies. This includes the fields of AGN, dynamically cold systems, super stellar and emission line clusters, and a more speculative ... More
The Formation of Massive Stars by Accretion Through Trapped Hypercompact HII RegionsSep 04 2003Jul 29 2004The formation of massive stars may take place at relatively low accretion rates over a long period of time if the accretion can continue past the onset of core hydrogen ignition. The accretion may continue despite the formation of an ionized HII region ... More
Hierarchical configurations for cross-correlation interferometers with many elementsSep 04 2012Array configurations built on a hierarchy of simple elements have excellent properties for cross-correlation imaging interferometers including a smooth distribution of measured Fourier components, high angular resolution, low side lobes, and compact array ... More
Quotient Stacks and String OrbifoldsMar 01 2001Oct 15 2001In this short review we outline some recent developments in understanding string orbifolds. In particular, we outline the recent observation that string orbifolds do not precisely describe string propagation on quotient spaces, but rather are literally ... More
Sudakov Effects in Higgs Production at the LHCMay 21 1997We discuss the resummation of Sudakov effects in a cross section from the viewpoint of its underlying factorization near the edge of phase space. We perform the resummation of Sudakov threshold logarithms in Higgs (Standard Model and Minimal Supersymmetric ... More
On Programs and GenomesOct 24 2011We outline the global control architecture of genomes. A theory of genomic control information is presented. The concept of a developmental control network called a cene (for control gene) is introduced. We distinguish parts-genes from control genes or ... More
Transformation of Zernike coefficients: A Fourier based method for scaled, translated and rotated wavefront aperturesFeb 28 2013This paper studies the effects on Zernike coefficients of aperture scaling, translation and rotation, when a given aberrated wavefront is described on the Zernike polynomial basis. It proposes a new analytical method for computing the matrix that enables ... More
Critère pour l'intégralité des coefficients de Taylor des applications miroirDec 18 2009We give a necessary and sufficient condition for the integrality of the Taylor coefficients of mirror maps at the origin. By mirror maps, we mean formal power series z.exp(G(z)/F(z)), where F(z) and G(z)+log(z)F(z) are particular solutions of certain ... More
Binary Disruption by Massive Black Holes in Globular ClustersJan 16 2005Mar 21 2005A massive (~10^2-10^4 Msun) black hole at the center of a globular cluster will tidally disrupt binaries that pass sufficiently close. Such an encounter results in the capture of one binary component by the black hole and ejection of the other star. A ... More
Detectability of Planck-Scale-Induced Blurring with Gamma-Ray BurstsJan 15 2015Microscopic fluctuations inherent to the fuzziness of spacetime at the Planck scale might accumulate in wavefronts propagating a cosmological distance and lead to noticeable blurring in an image of a pointlike source. Distant quasars viewed in the optical ... More
Are High-Redshift Quasars Blurry?Oct 13 2006It has been suggested that the fuzzy nature of spacetime at the Planck scale may cause lightwaves to lose phase coherence, and if severe enough this could blur images of distant point-like sources sufficiently that they do not form an Airy pattern at ... More
Deeply virtual Compton scattering off nucleiSep 16 2008Sep 24 2008Deeply virtual Compton scattering (DVCS) is the golden exclusive channel for the study of the partonic structure of hadrons, within the universal framework of generalized parton distributions (GPDs). This paper presents the aim and general ideas of the ... More
Fundamental Groups of Random Clique ComplexesJul 20 2012Feb 18 2013Clique complexes of Erd\H{o}s-R\'{e}nyi random graphs with edge probability between $n^{-{1\over 3}}$ and $n^{-{1\over 2}}$ are shown to be aas not simply connected. This entails showing that a connected two dimensional simplicial complex for which every ... More