We define double principal bundles (DPBs), for which the frame bundle of a double vector bundle, double Lie groups and double homogeneous spaces are basic examples. It is shown that a double vector bundle can be realized as the associated bundle of its frame bundle. Also dual structures, gauge transformations and connections in DPBs are investigated.

中文翻译：

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双主丛

我们定义了双主丛（DPBs），其中双向量丛的标架丛、双李群和双齐次空间是基本的例子。结果表明，一个双向量丛可以实现为其标架丛的相关丛。还研究了 DPB 中的双重结构、规范转换和连接。