TY - JOUR
T1 - Harmonic analysis on the space of p-adic unitary hermitian matrices, mainly for dyadic case
AU - Hironaka, Yumiko
PY - 2017/12
Y1 - 2017/12
N2 - We are interested in harmonic analysis on p-adic homogeneous spaces based on spherical functions. In the present paper, we investigate the space X of unitary hermitian matrices of size m over a p-adic field k mainly for dyadic case, and give the unified description with our previous papers for non-dyadic case. The space becomes complicated for dyadic case, and the set of integral elements in X has plural Cartan orbits. We introduce a typical spherical function ω(x; z) on X, study its functional equations, which depend on m and the ramification index e of 2 in k, and give its explicit formula, where Hall-Littlewood polynomials of type Cn appear as a main term with different specialization according as the parity m = 2n or 2n + 1, but independent of e. By spherical transform, we show the Schwartz space S(K\X) is a free Hecke algebra H(G, K)-module of rank 2n, and give parametrization of all the spherical functions on X and the explicit Plancherel formula on S(K\X). The Plancherel measure does not depend on e, but the normalization of G-invariant measure on X depends.
AB - We are interested in harmonic analysis on p-adic homogeneous spaces based on spherical functions. In the present paper, we investigate the space X of unitary hermitian matrices of size m over a p-adic field k mainly for dyadic case, and give the unified description with our previous papers for non-dyadic case. The space becomes complicated for dyadic case, and the set of integral elements in X has plural Cartan orbits. We introduce a typical spherical function ω(x; z) on X, study its functional equations, which depend on m and the ramification index e of 2 in k, and give its explicit formula, where Hall-Littlewood polynomials of type Cn appear as a main term with different specialization according as the parity m = 2n or 2n + 1, but independent of e. By spherical transform, we show the Schwartz space S(K\X) is a free Hecke algebra H(G, K)-module of rank 2n, and give parametrization of all the spherical functions on X and the explicit Plancherel formula on S(K\X). The Plancherel measure does not depend on e, but the normalization of G-invariant measure on X depends.
KW - Dyadic fields
KW - Hall-Littlewood polynomials
KW - Hermitian matrices
KW - Plancherel formula
KW - Spherical functions
KW - Unitary groups
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U2 - 10.3836/tjm/1502179240
DO - 10.3836/tjm/1502179240
M3 - Article
AN - SCOPUS:85040446279
VL - 40
SP - 517
EP - 564
JO - Tokyo Journal of Mathematics
JF - Tokyo Journal of Mathematics
SN - 0387-3870
IS - 2
ER -