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The Adelic Grassmannian and Exceptional Hermite Polynomials


It is shown that when dependence on the second flow of the KP hierarchy is added, the resulting semi-stationary wave function of certain points in George Wilson’s adelic Grassmannian are generating functions of the exceptional Hermite orthogonal polynomials. This surprising correspondence between different mathematical objects that were not previously known to be so closely related is interesting in its own right, but also proves useful in two ways: it leads to new algorithms for effectively computing the associated differential and difference operators and it also answers some open questions about them.

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Correspondence to Alex Kasman.

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Kasman, A., Milson, R. The Adelic Grassmannian and Exceptional Hermite Polynomials. Math Phys Anal Geom 23, 40 (2020).

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  • Bispectrality
  • KP hierarchy
  • Exceptional orthogonal polynomials
  • Generating function
  • Hermite polynomials
  • Adelic grassmannian

Mathematics Subject Classification (2010)

  • 33C45
  • 33C47