Abstract
Let \(K: = {\rm{G}}{{\rm{L}}_n}({\cal O})\) denote the maximal compact subgroup of GLn(F), where F is a nonarchimedean local field with ring of integers \({\cal O}\). We study the decomposition of the space of locally constant functions on the unit sphere in Fn into irreducible K-modules; for F = ℚp, these are the p-adic analogues of spherical harmonics. As an application, we characterise the newform and conductor exponent of a generic irreducible admissible smooth representation of GLn(F) in terms of distinguished K-types. Finally, we compare our results to analogous results in the archimedean setting.
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Acknowledgements
Thanks are owed to Subhajit Jana for helpful discussions regarding newforms and matrix coefficients.
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Humphries, P. The newform K-type and p-adic spherical harmonics. Isr. J. Math. (2023). https://doi.org/10.1007/s11856-023-2581-x
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DOI: https://doi.org/10.1007/s11856-023-2581-x