{ "id": "1803.02775", "version": "v1", "published": "2018-03-07T17:14:21.000Z", "updated": "2018-03-07T17:14:21.000Z", "title": "Dualities in the $q$-Askey scheme and degenerated DAHA", "authors": [ "Tom H. Koornwinder", "Marta Mazzocco" ], "comment": "44 pages, 1 figure", "categories": [ "math.CA", "math.QA", "nlin.SI" ], "abstract": "The Askey-Wilson polynomials are a four-parameter family of orthogonal symmetric Laurent polynomials $R_n[z]$ which are eigenfunctions of a second-order $q$-difference operator $L$, and of a second-order difference operator in the variable $n$ with eigenvalue $z + z^{-1}=2x$. Then $L$ and multiplication by $z+z^{-1}$ generate the Askey-Wilson (Zhedanov) algebra. A nice property of the Askey-Wilson polynomials is that the variables $z$ and $n$ occur in the explicit expression in a similar and to some extent exchangeable way. This property is called duality. It returns in the non-symmetric case and in the underlying algebraic structures: the Askey-Wilson algebra and the double affine Hecke algebra (DAHA). In this paper we follow the degeneration of the Askey-Wilson polynomials until two arrows down and in four diferent situations: for the orthogonal polynomials themselves, for the degenerate Askey-Wilson algebras, for the non-symmetric polynomials and for the (degenerate) DAHA and its representations.", "revisions": [ { "version": "v1", "updated": "2018-03-07T17:14:21.000Z" } ], "analyses": { "subjects": [ "33D45", "33D80", "33D52", "16T99" ], "keywords": [ "askey scheme", "degenerated daha", "askey-wilson polynomials", "orthogonal symmetric laurent polynomials", "second-order difference operator" ], "note": { "typesetting": "TeX", "pages": 44, "language": "en", "license": "arXiv", "status": "editable" } } }