General geronimus perturbations for mixed multiple orthogonal polynomials

General Geronimus transformations, defined by regular matrix polynomials that are neither required to be monic nor restricted by the rank of their leading coefficients, are applied through both right and left multiplication to a rectangular matrix of measures associated with mixed multiple orthogona...

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Detalles Bibliográficos
Autores: Mañas Baena, Manuel Enrique, Rojas Gómez, Miguel Ángel
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/124486
Acceso en línea:https://hdl.handle.net/20.500.14352/124486
Access Level:acceso abierto
Palabra clave:51-73
Mixed multiple orthogonal polynomials
Geronimus perturbations
Christoffel formulas
Spectral theory of matrix polynomials
Física matemática
2212 Física Teórica
Descripción
Sumario:General Geronimus transformations, defined by regular matrix polynomials that are neither required to be monic nor restricted by the rank of their leading coefficients, are applied through both right and left multiplication to a rectangular matrix of measures associated with mixed multiple orthogonal polynomials. These transformations produce Christoffel-type formulas that establish relationships between the perturbed and original polynomials. Moreover, it is proven that the existence of Geronimus-perturbed orthogonality is equivalent to the non-cancellation of certain τ -determinants. The effect of these transformations on the Markov-Stieltjes matrix functions is also determined. As a case study, we examine the Jacobi–Piñeiro orthogonal polynomials with three weights.