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arXiv · q-alg/9705006

Separation of variables and integral relations for special functions

Vadim B. Kuznetsov·Evgueni K. Sklyanin
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Abstract

We show that the method of separation of variables gives a natural generalisation of integral relations for classical special functions of one variable. The approach is illustrated by giving a new proof of the ``quadratic'' integral relations for the continuous q-ultraspherical polynomials. The separating integral operator M expressed in terms of the Askey-Wilson operator is studied in detail: apart from writing down the characteristic (``separation'') equations it satisfies, we find its spectrum, eigenfunctions, inversion, invariants (invariant q-difference operators), and give its interpretation as a fractional q-integration operator. We also give expansions of the A1 Macdonald polynomials into the eigenfunctions of the separating operator M and vice versa.

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BibTeXRIS

Vadim B. Kuznetsov, Evgueni K. Sklyanin. 1997-05-08. Separation of variables and integral relations for special functions. https://doi.org/10.1023/a%3A1009880307186

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