In this note, we introduce the notion of almost unramified representations of quasi-split unitary groups of even ranks with respect to an unramified quadratic extension of local fields, and study their behavior under the local theta correspondence. These representations are in some sense the least ramified representations that have root number −1.

中文翻译：

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酉群的几乎无分支表示的 Theta 对应

在本笔记中，我们介绍了关于局部场的无分支二次扩展的偶数秩准分裂酉群的几乎无分支表示的概念，并研究它们在局部 theta 对应下的行为。这些表示在某种意义上是根数为 -1 的最少分支表示。