This is an essay about general covariance, and what it says (or doesn’t say) about spacetime structure. After outlining a version of the dynamical approach to spacetime theories, and how it struggles to deal with generally covariant theories, I argue that we should think about the symmetry structure of spacetime rather differently in generally-covariant theories compared to non-generally-covariant theories: namely, as a form of internal rather than external symmetry structure.

中文翻译：

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广义相对论协方差

这是一篇关于一般协方差的文章，以及它说（或不说）关于时空结构的内容。在概述了时空理论的动力学方法的一个版本，以及它如何努力处理一般协变理论之后，我认为，与非一般协变理论相比，我们应该在一般协变理论中以截然不同的方式思考时空的对称结构：即，作为一种形式的内部而不是外部对称结构。