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arXiv · 2505.06969

Non-decreasable K-types are unitarily small

Chao-Ping Dong·Chengyu Du·Haojun Xu
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Abstract

Let $G$ be a connected simple non-compact real reductive Lie group with a maximal compact subgroup $K$. This note aims to show that any non-decreasable $K$-type (in the sense of the first named author) is unitarily small (in the sense of Salamanca-Riba and Vogan). This answers Conjecture 2.1 of \cite{D} in the affirmative.

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Chao-Ping Dong, Chengyu Du, Haojun Xu. 2025-05-11. Non-decreasable K-types are unitarily small. https://arxiv.org/abs/2505.06969

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