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arXiv 2404.06375gr-qcastro-ph.COhep-th
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演生修正引力

Emergent Modified Gravity

Martin Bojowald, Erick I. Duque

AI总结:

本文利用广义协变性的完整正则表述,引入区别于演生时空度规的基本引力场以规避唯一性定理,构建非高曲率修正引力理论,并给出宇宙学耦合、无额外场MOND及量子引力一致性等结果。

摘要:

广义协变性的完整正则表述使构建非高曲率形式的新型修正引力理论成为可能,本文在球对称情形下展示了这一点。通常的唯一性定理通过使用一个关键而新颖的要素被规避:允许引力的基本场不同于为所有解提供几何结构的演生时空度规。作为具体例子,宇宙学模型中出现了新的膨胀–剪切耦合;一种修正牛顿动力学(MOND)形式可以在不引入额外场的情况下出现在时空协变理论中;相关效应有助于使正则量子引力的有效模型与广义协变性完全一致。

英文摘要:

A complete canonical formulation of general covariance makes it possible to construct new modified theories of gravity that are not of higher-curvature form, as shown here in a spherically symmetric setting. The usual uniqueness theorems are evaded by using a crucial and novel ingredient, allowing for fundamental fields of gravity distinct from an emergent space-time metric that provides a geometrical structure to all solutions. As specific examples, there are new expansion-shear couplings in cosmological models, a form of modified Newtonian dynamics (MOND) can appear in a space-time covariant theory without introducing extra fields, and related effects help to make effective models of canonical quantum gravity fully consistent with general covariance.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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