95,633 research outputs found

    Hopf Algebras, Renormalization and Noncommutative Geometry

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    We explore the relation between the Hopf algebra associated to the renormalization of QFT and the Hopf algebra associated to the NCG computations of transverse index theory for foliations.Comment: 49 pages, Latex, 14 Fig's using eps

    Asset ownership and Asset Values Over Project Lifecycles

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    This paper develops a theory of outside ownership where such an ownership arrangement mitigates an external finance problem. Part of the gains from outside ownership accrue to asset owners which determines the asset value. The theory provides a context to analyze asset ownership and asset values over project lifecycles. When there are adjustment costs in realizing the full gains from outside ownership, (i) assets take time to peak in value, and (ii) the outsiders's share of asset ownership increases gradualAsset ownership; Asset value; Project lifecycles; Entry and exit

    The vacuum preserving Lie algebra of a classical W-algebra

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    We simplify and generalize an argument due to Bowcock and Watts showing that one can associate a finite Lie algebra (the `classical vacuum preserving algebra') containing the M\"obius sl(2)sl(2) subalgebra to any classical \W-algebra. Our construction is based on a kinematical analysis of the Poisson brackets of quasi-primary fields. In the case of the \W_\S^\G-algebra constructed through the Drinfeld-Sokolov reduction based on an arbitrary sl(2)sl(2) subalgebra §\S of a simple Lie algebra \G, we exhibit a natural isomorphism between this finite Lie algebra and \G whereby the M\"obius sl(2)sl(2) is identified with §\S.Comment: 11 pages, BONN-HE-93-25, DIAS-STP-93-13. Some typos had been removed, no change in formula

    SUSTAINABLE DEVELOPMENT IN THE GLOBAL ECONOMY

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    The actual paper comes with an approach regarding the sustainable development in today’s world and the global economy. The way of proceeding is the following: the main causes of the current economic crisis are analyzed and it is demonstrated that applyingsustainable development, global economy, crisis, environmental technologies

    Two-Phased Intra-Cluster Medium in the Centaurus Cluster of Galaxies

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    ASCA and ROSAT data of the Centaurus cluster were analyzed. A central excess in the radial brightness profile is found in the hard energy band up to 10keV. This requires a deeper central potential than a King-type one. A double-beta brightness distribution gives a good account of the data. A deprojected energy spectrum within a spherical region of radius 30 kpc at the cluster center indicates that the ICM cannot be isothermal there. Simultaneous fitting of the three (PSPC, GIS, and SIS) energy spectra extracted from the central 3' region showed that a two-temperature model that has temperatures of 1.4keV and 4.4keV and a common metallicity of 1.0 solar with the Galactic absorption gives the best description to the spectra. A cooling-flow spectral model did not give satisfactory fit. A 3-dimensional cluster model incorporating the two-phase picture, the double-beta brightness distribution, and the central metallicity increase reproduced the overall ASCA and ROSAT data successfully. The derived spatial distribution of the dark matter deviates from a King-type profile exhibiting a central excess, which is consistent with the Navvaro-Frenk-White model. The iron is revealed to be more widely spread than stars, which may have been caused by energetic supernovae and the motion of the cD galaxy. Since the derived characteristics of the cool phase including the temperature, angular extent, gas mass, and metallicity, are on a smooth extension of those of inter-stellar medium (ISM) of elliptical galaxies, the cool phase can be regarded as the ISM associated with the cD galaxy. The cool-phase X-ray emission is presumably sustained by energies dissipated by infalling mass to the cD galaxy in the course of cluster evolution.Comment: accepted for publication in Ap

    Diffractive eta_c photo-and electroproduction with the perturbative QCD Odderon

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    Using a set of new odderon states, we calculate their contribution to the diffractive eta_c photo- and electroproduction process. Compared to previous simple 3-gluon exchange calculations we find an enhancement of about one order of magnitude in the cross section. The t-dependence of the cross section exhibits a dip structure in the small t region.Comment: 16 pages, 3 eps figure

    New N=1 Extended Superconformal Algebras with Two and Three Generators

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    In this paper we consider extensions of the super Virasoro algebra by one and two super primary fields. Using a non-explicitly covariant approach we compute all SW-algebras with one generator of dimension up to 7 in addition to the super Virasoro field. In complete analogy to W-algebras with two generators most results can be classified using the representation theory of the super Virasoro algebra. Furthermore, we find that the SW(3/2, 11/2)-algebra can be realized as a subalgebra of SW(3/2, 5/2) at c = 10/7. We also construct some new SW-algebras with three generators, namely SW(3/2, 3/2, 5/2), SW(3/2, 2, 2) and SW(3/2, 2, 5/2).Comment: 30 pages (Plain TeX), BONN-HE-92-0

    Teleparallelism: A New Insight Into Gravity

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    Teleparallel gravity, a gauge theory for the translation group, turns up as fully equivalent to Einstein's general relativity. In spite of this equivalence, it provides a whole new insight into gravitation. It breaks several paradigms related to the geometric approach of general relativity, and introduces new concepts in the description of the gravitational interaction. The purpose of this chapter is to explore some of these concepts, as well as discuss possible consequences for gravitation, mainly those that could be relevant for the quantization of the gravitational field.Comment: Chapter to appear in "Handbook of Spacetime", edited by A. Ashtekar and V. Petcov (Springer, Berlin, 2013). V2: misprints corrected, references update

    INNOVATION PERFORMANCE FACTOR OF ECONOMIC ENTITIES

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    Innovation is the base of economic growth and there for it must be sustained with research and development. The economic enterprises to survive on market, they must became competitive and generate performances there for they have to be innovative. In Romania the innovative entities are unevenly distributed and in time the number of them has growth. There for in this work the inovative entities are treated from the standpoint of economic regions (macroregions 1, 2, 3, 4), years (2002-2006) and economic activity or branchinnovation, performance, economic entities, development, research, economic regions

    Molecular Cloud Structure in the Magellanic Clouds: Effect of Metallicity

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    The chemical structure of neutral clouds in low metallicity environments is examined with particular emphasis on the H to H_2 and C+ to CO transitions. We observed near-IR H_2 lines and the CO J=1-0 line from 30 Doradus and N159/N160 in the Large Magellanic Cloud and from DEM S 16, DEM S 37, and LI-SMC 36 in the Small Magellanic Cloud. We find that the H_2 emission is UV-excited and that (weak) CO emission always exists (in our surveyed regions) toward positions where H_2 and [CII] emission have been detected. Using a PDR code and a radiative transfer code, we simulate the emission of line radiation from spherical clouds and from large planar clouds. Because the [CII] emission and H_2 emission arise on the surface of the cloud and the lines are optically thin, these lines are not affected by changes in the relative sizes of the neutral cloud and the CO bearing core, while the optically thick CO emission can be strongly affected. The sizes of clouds are estimated by measuring the deviation of CO emission strength from that predicted by a planar cloud model of a given size. The average cloud column density and therefore size increases as the metallicity decreases. Our result agrees with the photoionization regulated star formation theory by Mc Kee (1989).Comment: 45 Pages including 15 figures. To be published in the ApJ May 10, 1998 issue, Vol. 49
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