We consider the classic question posed by Pardo and Spergel about the price of abandoning dark matter in the context of an invariant, metric-based theory of gravity. Our answer is that the price is nonlocality. This has been known for some time in the context of the quasi-static regime. We show that it also applies for cosmology and we exhibit a model which reproduces standard CDM successes such as perturbations in the cosmic microwave background, baryon acoustic oscillations and structure formation.

中文翻译：

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放弃暗物质的代价是非定域性

我们考虑帕尔多和斯佩格尔提出的经典问题，即在不变的、基于度量的引力理论的背景下放弃暗物质的代价。我们的答案是价格是非定域性的。在准静态制度的背景下，这一点已经为人所知一段时间了。我们证明它也适用于宇宙学，并且我们展示了一个模型，该模型再现了标准 CDM 的成功，例如宇宙微波背景的扰动、重子声振荡和结构形成。