Results for "Adina Feinstein"

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Essential Spectrum of the Weighted Laplacian on Noncompact Manifolds and ApplicationsAug 04 2016We obtain upper estimates for the bottom (that is, greatest lower bound) of the essential spectrum of weighted Laplacian operator of a weighted manifold under assumptions of the volume growth of their geodesic balls and spheres. Furthermore, we find examples ... More
eleanor: An open-source tool for extracting light curves from the TESS Full-Frame ImagesMar 21 2019During its two year prime mission the Transiting Exoplanet Survey Satellite (TESS) will perform a time-series photometric survey covering over 80% of the sky. This survey comprises observations of 26 24 x 96 degree sectors that are each monitored continuously ... More
Co-word Maps and Topic Modeling: A Comparison Using Small and Medium-Sized Corpora (n < 1000)Nov 10 2015Feb 26 2016Induced by "big data," "topic modeling" has become an attractive alternative to mapping co-words in terms of co-occurrences and co-absences using network techniques. Does topic modeling provide an alternative for co-word mapping in research practices ... More
Moduli spaces of rank 3 parabolic bundles over a many-punctured surfaceMar 18 2019Let $M$ be the moduli space of rank 3 parabolic vector bundles over a Riemann surface with several punctures. By the Mehta-Seshadri correspondence, this is the space of rank 3 unitary representations of the fundamental group of the punctured surface with ... More
Biharmonic submanifolds with parallel mean curvature vector field in spheresNov 08 2010Feb 08 2011We present some results on the boundedness of the mean curvature of proper biharmonic submanifolds in spheres. A partial classification result for proper biharmonic submanifolds with parallel mean curvature vector field in spheres is obtained. Then, we ... More
Character and Multiplicity Formulas for Compact Hamiltonian G-spacesNov 03 2014Let K $\subset$ G be compact connected Lie groups with common maximal torus T. Let (M, $\omega$) be a prequantisable compact connected symplectic manifold with a Hamiltonian G-action. Geometric quantisation gives a virtual representation of G; we give ... More
Financial Contagion and Asset Liquidation StrategiesJun 02 2015This paper provides a framework for modeling the financial system with multiple illiquid assets during a crisis. This extends the network model of Cifuentes, Shin & Ferrucci (2005) that incorporates a single asset with fire sales. We prove sufficient ... More
Formation of a Black String in a Higher Dimensional Vacuum Gravitational CollapseJun 12 2006Mar 31 2008We present a solution to the vacuum Einstein Equations which represents a collapse of a gravitational wave in 5 dimensions. Depending on the focal length of the wave, the collapse results, either in a black string covered by a horizon, or in a naked singularity ... More
It's a Trap: Emperor Palpatine's Poison PillNov 29 2015In this paper we study the financial repercussions of the destruction of two fully armed and operational moon-sized battle stations ("Death Stars") in a 4-year period and the dissolution of the galactic government in Star Wars. The emphasis of this work ... More
Exact Inflationary Solutions from a SuperpotentialMay 04 2000We propose a novel, potentially useful generating technique for constructing exact solutions of inflationary scalar field cosmologies with non-trivial potentials. The generating scheme uses the so-called superpotential and is inspired by recent studies ... More
Power-Law Inflation from the Rolling TachyonApr 17 2002Sep 09 2002Modeling the potential by an inverse square law in terms of the tachyon field ($V(T)=\beta T^{-2}$) we find exact solution for spatially flat isotropic universe.We show that for $\beta>2\sqrt{3}/3$ the model undergoes power-law inflation. A way to construct ... More
Some aspects of pre big bang cosmologyJun 01 2001This is a summary of a course given at the Fourth Mexican School on Gravitation and Mathematical Physics on some aspects of PBB cosmology. After introductory remarks the lectures concentrate on some amusing consequences derived from the symmetries of ... More
Geometry of the intersection ring and vanishing relations in the cohomology of the moduli space of parabolic bundles on a curveFeb 02 2015Aug 03 2015We study the ring generated by the Chern classes of tautological line bundles on the moduli space of parabolic bundles of arbitrary rank on a Riemann surface. We show the Poincar\'e duals to these Chern classes have simple geometric representatives. We ... More
A proof of equivalence between level lines shortening and curvature motion in image processingFeb 07 2011Feb 06 2012In this paper we define the continuous Level Lines Shortening evolution of a two-dimensional image as the Curve Shortening operator acting simultaneously and independently on all the level lines of the initial data, and show that it computes a viscosity ... More
Relations in the cohomology ring of the moduli space of flat $SO(2n+1)$-connections on a Riemann surfaceJan 12 2018We consider the moduli space of flat $SO(2n+1)$-connections (up to gauge transformations) on a Riemann surface, with fixed holonomy around a marked point. There are natural line bundles over this moduli space; we construct geometric representatives for ... More
Relations in the cohomology ring of the moduli space of flat $SO(2n+1)$-connections on a Riemann surfaceJan 12 2018Mar 18 2019We consider the moduli space of flat $SO(2n+1)$-connections (up to gauge transformations) on a Riemann surface, with fixed holonomy around a marked point. There are natural line bundles over this moduli space; we construct geometric representatives for ... More
Partial regularity and t-analytic sets for Banach function algebrasDec 29 2014In this note we introduce the notion of $t$-analytic sets. Using this concept, we construct a class of closed prime ideals in Banach function algebras and discuss some problems related to Alling's conjecture in $H^\infty$. A description of all closed ... More
Optimization of Fire Sales and Borrowing in Systemic RiskFeb 12 2018Oct 01 2018This paper provides a framework for modeling financial contagion in a network subject to fire sales and price impacts, but allowing for firms to borrow to cover their shortfall as well. We consider both uncollateralized and collateralized loans. The main ... More
Multiportfolio time consistency for set-valued convex and coherent risk measuresDec 21 2012Oct 10 2014Equivalent characterizations of multiportfolio time consistency are deduced for closed convex and coherent set-valued risk measures on $L^p(\Omega,\mathcal F, P; R^d)$ with image space in the power set of $L^p(\Omega,\mathcal F_t,P;R^d)$. In the convex ... More
Searching for evidence of jet-cloud interaction in radio galaxies. First results for 3C 381Jan 10 2013We present results of Gemini spectroscopy and Hubble Space Telescope imaging of the 3C~381 radio galaxy. Possible ionising mechanisms for the Extended Emission-Line Region were studied through state-of-the-art diagnostic analysis employing line-ratios. ... More
Strong Ditkin algebras without bounded relative unitsSep 09 1998Nov 13 1998In a previous note the author gave an example of a strong Ditkin algebra which does not have bounded relative units in the sense of Dales. In this note we investigate a certain family of Banach function algebras on the one point compactification of the ... More
A comparison of techniques for dynamic multivariate risk measuresMay 09 2013Jan 29 2015This paper contains an overview of results for dynamic multivariate risk measures. We provide the main results of four different approaches. We will prove under which assumptions results within these approaches coincide, and how properties like primal ... More
Scanning Tunneling Spectroscopy of Graphene on GraphiteMar 28 2008Jun 11 2009We report low temperature high magnetic field scanning tunneling microscopy and spectroscopy of graphene flakes on graphite that exhibit the structural and electronic properties of graphene decoupled from the substrate. Pronounced peaks in the tunneling ... More
Heun functions and combinatorial identitiesJan 08 2018We give closed forms for several families of Heun functions related to classical entropies. By comparing two expressions of the same Heun function, we get several combinatorial identities generalizing some classical ones.
Do latent tree learning models identify meaningful structure in sentences?Sep 04 2017Feb 26 2018Recent work on the problem of latent tree learning has made it possible to train neural networks that learn to both parse a sentence and use the resulting parse to interpret the sentence, all without exposure to ground-truth parse trees at training time. ... More
Dialogue Concerning The Two Chief World ViewsMay 26 2016In 1632, Galileo Galilei wrote a book called \textit{Dialogue Concerning the Two Chief World Systems} which compared the new Copernican model of the universe with the old Ptolemaic model. His book took the form of a dialogue between three philosophers, ... More
Ghosts in a MirrorApr 08 2003Apr 12 2003We look at some dynamic geometries produced by scalar fields with both the "right" and the "wrong" sign of the kinetic energy. We start with anisotropic homogeneous universes with closed, open and flat spatial sections. A non-singular solution to the ... More
Trivial Jensen measures without regularityDec 20 1999Dec 29 2014In this note we construct Swiss cheeses X such that R(X) is non-regular but such that R(X) has no non-trivial Jensen measures. We also construct a non-regular uniform algebra with compact, metrizable character space such that every point of the character ... More
A Supermartingale Relation for Multivariate Risk MeasuresOct 19 2015Jan 31 2018The equivalence between multiportfolio time consistency of a dynamic multivariate risk measure and a supermartingale property is proven. Furthermore, the dual variables under which this set-valued supermartingale is a martingale are characterized as the ... More
Time consistency of dynamic risk measures in markets with transaction costsJan 06 2012Dec 21 2012The paper concerns primal and dual representations as well as time consistency of set-valued dynamic risk measures. Set-valued risk measures appear naturally when markets with transaction costs are considered and capital requirements can be made in a ... More
A Supermartingale Relation for Multivariate Risk MeasuresOct 19 2015May 25 2016The equivalence between multiportfolio time consistency of a dynamic multivariate risk measure and a supermartingale property is proven. Furthermore, the dual variables under which this set-valued supermartingale is a martingale are characterized as the ... More
The fingerprints of Photoionization and Shock-Ionization in two CSS sourcesOct 23 2015We investigate the ionization state of the Extended Emission-Line Regions (EELRs) around two compact steep-spectrum (CSS) radio galaxies, 3C~268.3 and 3C~303.1, in order to identify the contribution of photoionization and shock-ionization. We perform ... More
A counterexample to a conjecture of S.E. MorrisOct 13 2003We give a counterexample to a conjecture of S.E. Morris by showing that there is a compact plane set X such that R(X) has no non-zero, bounded point derivations but such that R(X) is not weakly amenable. We also give an example of a separable uniform ... More
Trapping Regions for the Navier-Stokes EquationsApr 18 2004Oct 27 2014In 1999, J.C. Mattingly and Ya. G. Sinai used elementary methods to prove the existence and uniqueness of smooth solutions to the 2D Navier-Stokes equations with periodic boundary conditions. And they were almost successful in proving the existence and ... More
Countable linear combinations of characters on commutative Banach algebrasDec 24 2014An elegant but elementary result of Wolff from 1921, when interpreted in terms of Banach algebras, shows that it is possible to find a sequence of distinct characters $\phi_n$ on the disc algebra and an $\ell_1$ sequence of complex numbers $\lambda_n$, ... More
A recursive algorithm for multivariate risk measures and a set-valued Bellman's principleAug 10 2015Jul 04 2016A method for calculating multi-portfolio time consistent multivariate risk measures in discrete time is presented. Market models for $d$ assets with transaction costs or illiquidity and possible trading constraints are considered on a finite probability ... More
Shock-ionization in the Extended Emission-Line Region of 3C~305. The last piece of the (optical) puzzleJul 29 2013We present new Gemini spectroscopical data of the Extended Emission-Line Region of 3C~305 radio galaxy in order to achieve the final answer of the long-standing question about the ionizing mechanism. The spectra show strong kinematic disturbances within ... More
A Supermartingale Relation for Multivariate Risk MeasuresOct 19 2015Nov 15 2016The equivalence between multiportfolio time consistency of a dynamic multivariate risk measure and a supermartingale property is proven. Furthermore, the dual variables under which this set-valued supermartingale is a martingale are characterized as the ... More
Convergence from below sufficesDec 24 2014An elementary application of Fatou's lemma gives a strengthened version of the monotone convergence theorem. We call this the convergence from below theorem. We make the case that this result should be better known, and deserves a place in any introductory ... More
Computation of Resistive WakefieldsJan 07 2009We evaluate longitudinal resistive wakefields for cylindrical beam pipes numerically and compare the results with existing approximate formul\ae. We consider an ultra-relativistic bunch traversing a cylindrical, metallic tube for a model in which the ... More
Biharmonic PNMC Submanifolds in SpheresOct 19 2011We obtain several rigidity results for biharmonic submanifolds in $\mathbb{S}^{n}$ with parallel normalized mean curvature vector field. We classify biharmonic submanifolds in $\mathbb{S}^{n}$ with parallel normalized mean curvature vector field and with ... More
The second-order analysis of marked spatio-temporal point processes, with an application to earthquake dataNov 15 2016To analyse interaction in marked spatio-temporal point processes (MSTPPs), we introduce marked (cross) second-order reduced moment measures and K-functions for general inhomogeneous second-order intensity reweighted stationary MSTPPs. These summary statistics, ... More
A Broad-Coverage Challenge Corpus for Sentence Understanding through InferenceApr 18 2017Feb 19 2018This paper introduces the Multi-Genre Natural Language Inference (MultiNLI) corpus, a dataset designed for use in the development and evaluation of machine learning models for sentence understanding. In addition to being one of the largest corpora available ... More
Morphisms of Berkovich curves and the different functionAug 13 2014Aug 31 2016Given a generically \'etale morphism $f\colon Y\to X$ of quasi-smooth Berkovich curves, we define a different function $\delta_f\colon Y\to[0,1]$ that measures the wildness of the topological ramification locus of $f$. This provides a new invariant for ... More
Relativistic hydrodynamics with sources for cosmological K-fluidsJan 31 2005Oct 11 2005We consider hydrodynamics with non conserved number of particles and show that it can be modeled with effective fluid Lagrangians which explicitly depend on the velocity potentials. For such theories, the {}``shift symetry'' $\phi\to\phi+$const. leading ... More
Quasianalyticity in certain Banach function algebrasMay 16 2016Let $X$ be a perfect, compact subset of the complex plane. We consider algebras of those functions on $X$ which satisfy a generalised notion of differentiability, which we call $\mathcal{F}$-differentiability. In particular, we investigate a notion of ... More
The Effects of Leverage Requirements and Fire Sales on Financial Contagion via Asset Liquidation Strategies in Financial NetworksJul 07 2015This paper provides a framework for modeling the financial system with multiple illiquid assets when liquidation of illiquid assets is caused by failure to meet a leverage requirement. This extends the network model of Cifuentes, Shin & Ferrucci (2005) ... More
Compact endomorphisms of H infinity of DOct 21 1998When G is a region in the complex plane, compact composition operators on the uniform algebra of bounded analytic functions on G and the spectra of these operators were described by D. Swanton, Compact composition operators on B(D), Proc. Amer. Math. ... More
Power-law expansion in k-essence cosmologyApr 30 2003Nov 10 2003We study spatially flat isotropic universes driven by k-essence. It is shown that Friedmann and k-field equations may be analytically integrated for arbitrary k-field potentials during evolution with a constant baryotropic index. It follows that there ... More
Riesz endomorphisms of Banach algebrasMar 25 2004Let B be a unital commutative semi-simple Banach algebra. We study endomorphisms of B which are simultaneously Riesz operators. Clearly compact and power compact endomorphisms are Riesz. Several general theorems about Riesz endomorphisms are proved, and ... More
Compact endomorphisms of Banach algebras of infinitely differentiable functionsMay 02 2002Oct 12 2003We consider non-zero endomorphisms of the Dales and Davie algebras of infinitely differentiable functions on intervals in the real line. We discuss necessary and sufficient conditions for a selfmap of the interval to induce a compact endomorphism of these ... More
Quasicompact endomorphisms of commutative semiprime Banach algebrasDec 29 2014This paper is a continuation of our study of compact, power compact, Riesz, and quasicompact endomorphisms of commutative Banach algebras. Previously it has been shown that if $B$ is a unital commutative semisimple Banach algebra with connected character ... More
Endomorphisms of Banach algebras of infinitely differentiable functions on compact plane setsMay 20 1999In this note we study the endomorphisms of certain Banach algebras of infinitely differentiable functions on compact plane sets, associated with weight sequences M. These algebras were originally studied by Dales, Davie and McClure. In a previous paper ... More
The Homogeneous Scalar Field and the Wet Dark Sides of the UniverseApr 07 2006Jul 13 2006We study the possibility that a generalised real scalar field minimally coupled to gravity could explain both the galactic and the cosmological dark components of the universe. Within the framework of Einstein's Relativity we model static galactic halos ... More
Compact homomorphisms between Dales-Davie algebrasNov 06 2003In this note we consider compact homomorphisms and endomorphisms between various Dales-Davie algebras. In particular, we obtain fairly complete results when the underlying set is the disc or the unit circle. Comparable results when the underlying set ... More
Nonreproducible connectome changes hint at functional heterogeneity of Parkinson's DiseaseNov 15 2016Since anatomic MRI is presently not able to directly discern neuronal loss in Parkinson's Disease (PD), studying the associated functional connectivity (FC) changes seems a promising approach toward developing non-invasive and non-radioactive neuroimaging ... More
On the Idiosyncrasies of the Mandarin Chinese Classifier SystemFeb 26 2019While idiosyncrasies of the Chinese classifier system have been a richly studied topic among linguists (Adams and Conklin, 1973; Erbaugh, 1986; Lakoff, 1986), not much work has been done to quantify them with statistical methods. In this paper, we introduce ... More
The Effects of Leverage Requirements and Fire Sales on Financial Contagion via Asset Liquidation Strategies in Financial NetworksJul 07 2015Oct 13 2016This paper provides a framework for modeling the financial system with multiple illiquid assets when liquidation of illiquid assets is caused by failure to meet a leverage requirement. This extends the network model of Cifuentes, Shin & Ferrucci (2005) ... More
Accelerating Universes from Short-Range InteractionsMay 20 2005Oct 11 2005We show that short-range interactions between the fundamental particles in the universe can drive a period of accelerated expansion. This description fits the early universe. In the present day universe, if one postulates short-range interactions or a ... More
Regularity points and Jensen measures for $R(X)$Jul 07 2015We discuss two types of `regularity point', points of continuity and R-points for Banach function algebras, which were introduced by the first author and Somerset in an earlier paper on non-regularity for Banach function algebras. We show that, even for ... More
The RepEval 2017 Shared Task: Multi-Genre Natural Language Inference with Sentence RepresentationsJul 25 2017This paper presents the results of the RepEval 2017 Shared Task, which evaluated neural network sentence representation learning models on the Multi-Genre Natural Language Inference corpus (MultiNLI) recently introduced by Williams et al. (2017). All ... More
Automated Assignment of Backbone NMR Data using Artificial IntelligenceJun 18 2015Nuclear magnetic resonance (NMR) spectroscopy is a powerful method for the investigation of three-dimensional structures of biological molecules such as proteins. Determining a protein structure is essential for understanding its function and alterations ... More
Measures of Systemic RiskFeb 27 2015Mar 17 2016Systemic risk refers to the risk that the financial system is susceptible to failures due to the characteristics of the system itself. The tremendous cost of systemic risk requires the design and implementation of tools for the efficient macroprudential ... More
M-theory resolution of four-dimensional cosmological singularities via U-dualityJun 01 1999Feb 07 2000We consider cosmological solutions of string and M-theory compactified to four dimensions by giving a general prescription to construct four-dimensional modular cosmologies with two commuting Killing vectors from vacuum solutions. By lifting these solutions ... More
Generating Generalized $G_{D-2}$ solutionsApr 09 2008May 05 2008We show how one can systematically construct vacuum solutions to Einstein field equations with $D-2$ commuting Killing vectors in $D>4$ dimensions. The construction uses Einstein-scalar field seed solutions in 4 dimensions and is performed both for the ... More
Banach function algebras with dense invertible groupNov 03 2004In an earlier paper, Dawson and the second author asked whether or not a Banach function algebra with dense invertible group can have a proper Shilov boundary. We give an example of a uniform algebra showing that this can happen, and investigate the properties ... More
Extensions of endomorphisms of C(X)Oct 01 2004For a compact space X we consider extending endomorphisms of the algebra C(X) to be endomorphisms of Arens-Hoffman and Cole extensions of C(X). Given a non-linear, monic polynomial p in C(X)[t], with C(X)[t]/pC(X)[t] semi-simple, we show that if an endomorphism ... More
The chain rule for $\mathcal F$-differentiationNov 30 2015Dec 10 2015Let $X$ be a perfect, compact subset of the complex plane, and let $D^{(1)}(X)$ denote the (complex) algebra of continuously complex-differentiable functions on $X$. Then $D^{(1)}(X)$ is a normed algebra of functions but, in some cases, fails to be a ... More
Swiss cheeses, rational approximation and universal plane curvesJan 16 2015In this paper we consider the compact plane sets known as Swiss cheese sets, which are a useful source of examples in the theory of uniform algebras and rational approximation. We introduce a notion of 'allocation map' connected with Swiss cheeses, and ... More
Suppression of charge density wave phases in ultrathin 1T-TaS2Jun 12 2015Using temperature dependent Raman spectroscopy we address the question of how the transition from bulk to few atomic layers affects the charge density wave (CDW) phases in 1T-TaS2. We find that for crystals with thickness larger than approx 10nm the transition ... More
Large Time Behavior of Periodic Viscosity Solutions for Uniformly Elliptic Integro-Differential EquationsOct 21 2012In this paper, we study the large time behavior of solutions of a class of parabolic fully nonlinear integro-differential equations in a periodic setting. In order to do so, we first solve the ergodic problem}(or cell problem), i.e. we construct solutions ... More
Verb Argument Structure Alternations in Word and Sentence EmbeddingsNov 27 2018Verbs occur in different syntactic environments, or frames. We investigate whether artificial neural networks encode grammatical distinctions necessary for inferring the idiosyncratic frame-selectional properties of verbs. We introduce five datasets, ... More
Exploring the reproducibility of functional connectivity alterations in Parkinson's DiseaseNov 15 2016Sep 01 2017Since anatomic MRI is presently not able to directly discern neuronal loss in Parkinson's Disease (PD), studying the associated functional connectivity (FC) changes seems a promising approach toward developing non-invasive and non-radioactive neuroimaging ... More
Spectral synthesis for Banach Algebras IISep 24 1999May 12 2000This paper continues the study of spectral synthesis and the topologies $\tau_{\infty}$ and $\tau_r$ on the ideal space of a Banach algebra, concentrating particularly on the class of Haagerup tensor products of C$^*$-algebras. For this class, it is shown ... More
A note on ideal spaces of Banach AlgebrasSep 16 1998In a previous paper the second author introduced a compact topology on the space of closed ideals of a unital Banach algebra A. If A is separable then this topology is either metrizable or else neither Hausdorff nor first countable. Here it is shown that ... More
5D gravitational waves from complexified black ringsOct 20 2009Feb 01 2010In this paper we construct and briefly study the 5D time-dependent solutions of general relativity obtained via double analytic continuation of the black hole (Myers-Perry) and of the black ring solutions with a double (Pomeransky-Senkov) and a single ... More
Cosmologies with Two-Dimensional InhomogeneityNov 27 1995We present a new generating algorithm to construct exact non static solutions of the Einstein field equations with two-dimensional inhomogeneity. Infinite dimensional families of $G_1$ inhomogeneous solutions with a self interacting scalar field, or alternatively ... More
Identification and analysis of the young population in the starburst galaxy NGC 253Jun 18 2018We present a study of the young population in the starburst galaxy NGC 253. In particular, we focused our attention on searching young star groups, obtaining their main properties and studying their hierarchical organization. For this task, we used multiband ... More
Swiss Cheeses and Their ApplicationsDec 19 2014Swiss cheese sets have been used in the literature as useful examples in the study of rational approximation and uniform algebras. In this paper, we give a survey of Swiss cheese constructions and related results. We describe some notable examples of ... More
On the denseness of the invertible group in Banach algebrasMar 26 2002We examine the condition that a complex Banach algebra $A$ have dense invertible group. We show that, for commutative algebras, this property is preserved by integral extensions. We also investigate the connections with an old problem in the theory of ... More
Removability of exceptional sets for differentiable and Lipschitz functionsDec 19 2014We discuss removability problems concerning differentiability and pointwise Lipschitz conditions for functions of a real variable. We prove that, in each of the settings under consideration, a set is removable if and only if it has no perfect subsets. ... 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
Measures of Systemic RiskFeb 27 2015Oct 13 2016Systemic risk refers to the risk that the financial system is susceptible to failures due to the characteristics of the system itself. The tremendous cost of systemic risk requires the design and implementation of tools for the efficient macroprudential ... More
Can the Type-IIB axion prevent Pre-big Bang inflation?Jun 19 1998We look at the possibility of superinflationary behavior in a class of anisotropic Type-IIB superstring cosmologies in the context of Pre-big Bang scenario and find that there exists a rather narrow range of parameters for which these models inflate. ... More
The Origin of the Entropy in the UniverseOct 15 1996Mar 13 1997We discuss the entropy generation in quantum tunneling of a relativistic particle under the influence of a time varying force with the help of squeezing formalism. It is shown that if one associates classical coarse grained entropy to the phase space ... More
Dynamic Clearing and Contagion in Financial NetworksJan 06 2018May 25 2018In this paper we will consider a generalized extension of the Eisenberg-Noe model of financial contagion to allow for time dynamics in both discrete and continuous time. Derivation and interpretation of the financial implications will be provided. Emphasis ... More
Regularity and amenability conditions for uniform algebrasDec 24 2014We give a survey of the known connections between regularity conditions and amenability conditions in the setting of uniform algebras. For a uniform algebra $A$ we consider the set, $A_{lc}$, of functions in $A$ which are locally constant on a (varying) ... More
Abstract Swiss Cheese Space and the Classicalisation of Swiss CheesesMar 12 2015Feb 03 2016Swiss cheese sets are compact subsets of the complex plane obtained by deleting a sequence of open disks from a closed disk. Such sets have provided numerous counterexamples in the theory of uniform algebras. In this paper, we introduce a topological ... More
Normed algebras of differentiable functions on compact plane setsJan 16 2015We investigate the completeness and completions of the normed algebras $D^{(1)}(X)$ for perfect, compact plane sets $X$. In particular, we construct a radially self-absorbing, compact plane set $X$ such that the normed algebra $D^{(1)}(X)$ is not complete. ... More
Strong regularity for uniform algebrasSep 14 1998A survey is given of the work on strong regularity for uniform algebras over the last thirty years, and some new results are proved, including the following. Let A be a uniform algebra on a compact space X and let E be the set of all those points x of ... 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
Disks in Expanding FRW UniversesJun 13 1997Oct 15 1997We construct exact solutions to Einstein equations which represent relativistic disks immersed into an expanding FRW Universe. It is shown that the expansion influences dynamical characteristics of the disks such as rotational curves, surface mass density, ... More
Particle Creation in the Bell-Szekeres SpacetimeNov 24 1995The quantization of a real massless scalar field in a spacetime produced in a collision of two electromagnetic plane waves with constant wave fronts is considered. The background geometry in the interaction region, the Bell-Szekeres solution, is locally ... More
Exponential-Potential Scalar Field Universes II: The Inhomogeneous ModelsSep 14 1993We obtain exact solutions for the Einstein equations with an exponential-potential scalar field (\(V=\Lambda e^{k\phi}\)) which represent simple inhomogeneous generalizations of Bianchi I cosmologies. Studying these equations numerically we find that ... More
Generating Black Strings in Higher DimensionsOct 22 2009Starting with a Zipoy-Voorhees line element we construct and study the three parameter family of solutions describing a deformed black string with arbitrary tension.
Exponential-Potential Scalar Field Universes I: The Bianchi I ModelsSep 14 1993We obtain a general exact solution of the Einstein field equations for the anisotropic Bianchi type I universes filled with an exponential-potential scalar field and study their dynamics. It is shown, in agreement with previous studies, that for a wide ... More
Detailed photometric analysis of young star groups in the galaxy NGC 300Aug 22 2016The purpose of this work is to understand the global characteristics of the stellar populations in NGC 300. In particular, we focused our attention on searching young star groups and study their hierarchical organization. The research was conducted using ... More
Completions of normed algebras of differentiable functionsOct 13 2003In this paper we look at normed spaces of differentiable functions on compact plane sets, including the spaces of infinitely differentiable functions originally considered by Dales and Davie. For many compact plane sets the classical definitions give ... More
The young stellar population in NGC 247 Main properties and hierarchical clusteringApr 22 2019The aim of this work is to investigate the characteristics of the young stellar population in the spiral galaxy NGC 247. In particular, we focused our attention in its hierarchical clustering distributions and the properties of the smallest groups. We ... More
HFF-DeepSpace Photometric Catalogs of the Twelve Hubble Frontier Fields, Clusters and Parallels: Photometry, Photometric Redshifts, and Stellar MassesJan 29 2018Jan 31 2018We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have ... More