1,125 research outputs found

    Mirror displacement energies and neutron skins

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    A gross estimate of the neutron skin [0.80(5)(NZ)/A(N-Z)/A fm] is extracted from experimental proton radii, represented by a four parameter fit, and observed mirror displacement energies (CDE). The calculation of the latter relies on an accurately derived Coulomb energy and smooth averages of the charge symmetry breaking potentials constrained to state of the art values. The only free parameter is the neutron skin itself. The Nolen Schiffer anomaly is reduced to small deviations (rms=127 keV) that exhibit a secular trend. It is argued that with state of the art shell model calculations the anomaly should disappear. Highly accurate fits to proton radii emerge as a fringe benefit.Comment: 4 pages 3 figures, superseeds first part of nucl-th/0104048 Present is new extended version: 5 pages 4 figures. Explains more clearly the achievements of the previous on

    Long Run Health Impacts of Income Shocks: Wine and Phylloxera in 19th Century France

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    This paper provides estimates of the long-term effects on height and health of a large income shock experienced in early childhood. Phylloxera, an insect that attacks the roots of grape vines, destroyed 40% of French vineyards between 1863 and 1890, causing major income losses among wine growing families. Because the insects spread slowly from the southern coast of France to the rest of the country, Phylloxera affected different regions in different years. We exploit the regional variation in the timing of this shock to identify its effects. We examine the effects on the adult height, health, and life expectancy of children born in the years and regions affected by the Phylloxera. The shock decreased long run height, but it did not affect other dimensions of health, including life expectancy. We find that, at age 20, those born in affected regions were about 1.8 millimeters shorter than others. This estimate implies that children of wine-growing families born when the vines were affected in their regions were 0.6 to 0.9 centimeters shorter than others by age 20. This is a significant effect since average heights grew by only 2 centimeters in the entire 19th century. However, we find no other effect on health, including infant mortality, life expectancy, and morbidity by age 20.

    Non-commutative holonomies in 2+1 LQG and Kauffman's brackets

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    We investigate the canonical quantization of 2+1 gravity with {\Lambda} > 0 in the canonical framework of LQG. A natural regularization of the constraints of 2+1 gravity can be defined in terms of the holonomies of A\pm = A \PM \surd{\Lambda}e, where the SU(2) connection A and the triad field e are the conjugated variables of the theory. As a first step towards the quantization of these constraints we study the canonical quantization of the holonomy of the connection A_{\lambda} = A + {\lambda}e acting on spin network links of the kinematical Hilbert space of LQG. We provide an explicit construction of the quantum holonomy operator, exhibiting a close relationship between the action of the quantum holonomy at a crossing and Kauffman's q-deformed crossing identity. The crucial difference is that the result is completely described in terms of standard SU(2) spin network states.Comment: 4 pages; Proceedings of Loops'11, Madrid, to appear in Journal of Physics: Conference Series (JPCS

    Casimir eigenvalues for universal Lie algebra

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    For two different natural definitions of Casimir operators for simple Lie algebras we show that their eigenvalues in the adjoint representation can be expressed polynomially in the universal Vogel's parameters α,β,γ\alpha, \beta, \gamma and give explicit formulae for the generating functions of these eigenvalues.Comment: Slightly revised versio

    L1-determined ideals in group algebras of exponential Lie groups

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    A locally compact group GG is said to be \ast-regular if the natural map \Psi:\Prim C^\ast(G)\to\Prim_{\ast} L^1(G) is a homeomorphism with respect to the Jacobson topologies on the primitive ideal spaces \Prim C^\ast(G) and \Prim_{\ast} L^1(G). In 1980 J. Boidol characterized the \ast-regular ones among all exponential Lie groups by a purely algebraic condition. In this article we introduce the notion of L1L^1-determined ideals in order to discuss the weaker property of primitive \ast-regularity. We give two sufficient criteria for closed ideals II of C(G)C^\ast(G) to be L1L^1-determined. Herefrom we deduce a strategy to prove that a given exponential Lie group is primitive \ast-regular. The author proved in his thesis that all exponential Lie groups of dimension 7\le 7 have this property. So far no counter-example is known. Here we discuss the example G=B5G=B_5, the only critical one in dimension 5\le 5

    Applications of the group SU(1,1) for quantum computation and tomography

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    This paper collects miscellaneous results about the group SU(1,1) that are helpful in applications in quantum optics. Moreover, we derive two new results, the first is about the approximability of SU(1,1) elements by a finite set of elementary gates, and the second is about the regularization of group identities for tomographic purposes.Comment: 11 pages, no figure

    Quantization of Wilson loops in Wess-Zumino-Witten models

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    We describe a non-perturbative quantization of classical Wilson loops in the WZW model. The quantized Wilson loop is an operator acting on the Hilbert space of closed strings and commuting either with the full Kac-Moody chiral algebra or with one of its subalgebras. We prove that under open/closed string duality, it is dual to a boundary perturbation of the open string theory. As an application, we show that such operators are useful tools for identifying fixed points of the boundary renormalization group flow.Comment: 24 pages. Version published in JHE

    Microscopic calculation of proton capture reactions in mass 60-80 region and its astrophysical implications

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    Microscopic optical potentials obtained by folding the DDM3Y interaction with the densities from Relativistic Mean Field approach have been utilized to evaluate S-factors of low-energy (p,γ)(p,\gamma) reactions in mass 60-80 region and to compare with experiments. The Lagrangian density FSU Gold has been employed. Astrophysical rates for important proton capture reactions have been calculated to study the behaviour of rapid proton nucleosynthesis for waiting point nuclei with mass less than A=80

    Indoor air pollution, health and economic well-being

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    Abstract. Indoor air pollution (IAP) caused by solid fuel use and/or traditional cooking stoves is a global health threat, particularly for women and young children. The WHO World Health Report 2002 estimates that IAP is responsible for 2.7% of the loss of disability adjusted life years (DALYs) worldwide and 3.7% in highmortality developing countries. Despite the magnitude of this problem, social scientists have only recently begun to pay closer attention to this issue and to test strategies for reducing IAP. In this paper, we provide a survey of the current literature on the relationship between indoor air pollution, respiratory health and economic well-being. We then discuss the available evidence on the effectiveness of popular policy prescriptions to reduce IAP within the household

    The Hopf Algebra of Renormalization, Normal Coordinates and Kontsevich Deformation Quantization

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    Using normal coordinates in a Poincar\'e-Birkhoff-Witt basis for the Hopf algebra of renormalization in perturbative quantum field theory, we investigate the relation between the twisted antipode axiom in that formalism, the Birkhoff algebraic decomposition and the universal formula of Kontsevich for quantum deformation.Comment: 21 pages, 15 figure
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