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    Coherent Orthogonal Polynomials

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    We discuss as a fundamental characteristic of orthogonal polynomials like the existence of a Lie algebra behind them, can be added to their other relevant aspects. At the basis of the complete framework for orthogonal polynomials we put thus --in addition to differential equations, recurrence relations, Hilbert spaces and square integrable functions-- Lie algebra theory. We start here from the square integrable functions on the open connected subset of the real line whose bases are related to orthogonal polynomials. All these one-dimensional continuous spaces allow, besides the standard uncountable basis ∣x>{|x>}, for an alternative countable basis ∣n>{|n>}. The matrix elements that relate these two bases are essentially the orthogonal polynomials: Hermite polynomials for the line and Laguerre and Legendre polynomials for the half-line and the line interval, respectively. Differential recurrence relations of orthogonal polynomials allow us to realize that they determine a unitary representation of a non-compact Lie algebra, whose second order Casimir C{\cal C} gives rise to the second order differential equation that defines the corresponding family of orthogonal polynomials. Thus, the Weyl-Heisenberg algebra h(1)h(1) with C=0{\cal C}=0 for Hermite polynomials and su(1,1)su(1,1) with C=−1/4{\cal C}=-1/4 for Laguerre and Legendre polynomials are obtained. Starting from the orthogonal polynomials the Lie algebra is extended both to the whole space of the L2{\cal L}^2 functions and to the corresponding Universal Enveloping Algebra and transformation group. Generalized coherent states from each vector in the space L2{\cal L}^2 and, in particular, generalized coherent polynomials are thus obtained.Comment: 11 page

    Calcificación idiopática de ganglios basales (síndrome de Fahr) y discinesias tardías tratadas con Diltiazem.

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    Se describe un caso de discinesias bucolinguo-masticatorias en un Síndrome de Fahr (Calcificación Idiopática de los ganglios basales, Trastornos del Movimiento, Anormalidades neuropsiquiátricas y Metabolismo del fósforo y calcio normal), revisándose la literatura y discutiéndose la buena respuesta de ambos, Síndrome de Fahr y discinesia tardía, al tratamiento con diltiazem a dosis de 90 mg/día
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