Mimetic Gravity: A Review of Recent Developments and Applications to Cosmology and Astrophysics
Mimetic Gravity: A Review of Recent Developments and Applications to Cosmology and Astrophysics
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DOI：
10.1155/2017/3156915
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发表时间：
2016-12
影响因子：
1.7
通讯作者：
L. Sebastiani;S. Vagnozzi;R. Myrzakulov
中科院分区：
文献类型：
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作者：
L. Sebastiani;S. Vagnozzi;R. Myrzakulov
拟态引力是广义相对论的韦尔对称扩展，通过奇异变形变换与后者相关，其中尘埃状完美流体的出现可以在宇宙学层面上模拟冷暗物质。在这个框架内，可以为暗物质、后期加速和膨胀提供统一的几何解释，使其成为一个非常有吸引力的理论。在这篇综述中，我们总结了拟态重力的主要方面，以及模型最小公式的扩展。我们特别关注重建技术，该技术允许通过准确选择理论中定义的势或其他函数（如模拟引力的情况）来实现任何所需的宇宙膨胀历史。我们简要讨论模拟引力中的宇宙微扰理论。作为应用前面讨论的概念的案例研究，我们研究了一种模仿 Hořava 的理论，我们详细探索了该理论的解决方案和宇宙学扰动。最后，我们通过讨论模拟重力内的静态球对称解来结束综述，并将我们的发现应用于银河旋转曲线问题。我们的综述介绍了拟态引力，并对最近的发现、进展、悬而未决的问题以及对未来研究方向的展望进行了简洁但独立的总结。
Mimetic gravity is a Weyl-symmetric extension of General Relativity, related to the latter by a singular disformal transformation, wherein the appearance of a dust-like perfect fluid can mimic cold dark matter at a cosmological level. Within this framework, it is possible to provide a unified geometrical explanation for dark matter, the late-time acceleration, and inflation, making it a very attractive theory. In this review, we summarize the main aspects of mimetic gravity, as well as extensions of the minimal formulation of the model. We devote particular focus to the reconstruction technique, which allows the realization of any desired expansionary history of the universe by an accurate choice of potential or other functions defined within the theory (as in the case of mimetic gravity). We briefly discuss cosmological perturbation theory within mimetic gravity. As a case study within which we apply the concepts previously discussed, we study a mimetic Hořava-like theory, of which we explore solutions and cosmological perturbations in detail. Finally, we conclude the review by discussing static spherically symmetric solutions within mimetic gravity and apply our findings to the problem of galactic rotation curves. Our review provides an introduction to mimetic gravity, as well as a concise but self-contained summary of recent findings, progress, open questions, and outlooks on future research directions.