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Coherent Orthogonal Polynomials
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 , for an alternative countable basis . 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 gives rise to the second order
differential equation that defines the corresponding family of orthogonal
polynomials. Thus, the Weyl-Heisenberg algebra with for
Hermite polynomials and with for Laguerre and
Legendre polynomials are obtained.
Starting from the orthogonal polynomials the Lie algebra is extended both to
the whole space of the functions and to the corresponding
Universal Enveloping Algebra and transformation group. Generalized coherent
states from each vector in the space and, in particular,
generalized coherent polynomials are thus obtained.Comment: 11 page
Calcificación idiopática de ganglios basales (sÃndrome de Fahr) y discinesias tardÃas tratadas con Diltiazem.
Se describe un caso de discinesias bucolinguo-masticatorias en un SÃndrome 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, SÃndrome de Fahr y discinesia tardÃa, al tratamiento con diltiazem a dosis de 90 mg/dÃa
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