Black hole thermodynamics, spacetime conformal mappings, cosmological perturbations, and modified gravity.

黑洞热力学、时空共形映射、宇宙扰动和修正引力。

• 批准号: RGPIN-2017-05388
• 负责人: Hammad, Fayçal
• 金额: $ 1.37万
• 依托单位: Bishop's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=710826
• 关键词: Black; hole; thermodynamics; spacetime; conformal

Nature of the work: The aim of this program is to achieve a better understanding of gravity, black holes, and the beginning as well as the evolution of the Universe. Black holes are regions of spacetime where matter is so dense that it literally forms holes in spacetime according to Einstein's General Relativity (GR) (the best theory of gravity we have today). I will examine more closely the evolution of black holes using one of theorists' favorite tools, called spacetime conformal mapping, for studying spacetime. This tool consists in changing the lengths and the duration of an event without changing the coordinates of that event. Since the thermodynamics and the mechanics of black holes are deeply intertwined, by studying the latter using this precious theoretical tool I will bring more light to the former. On the other hand, the increased precision of recent observations of the Cosmic Microwave Background (CMB) (a thermal radiation filling the sky) gives a precious tool to put to test any model of gravity that departs from GR. I will pursue my investigation on my recent model of modified gravity ((varying power)-law model) and confront it with the latest data from the sky. Finally, a very active research in gravitational physics recently is the use of thermodynamics to obtain the dynamics of the Universe. I will extend my previous research on this topic to obtain a link between cosmology and modified gravity theories in view of providing all the possible theoretical constraints on both. Importance of the research: This work will contribute to our understanding of black holes, and to our understanding of the Universe and its evolution. Expected results: Spacetime thermodynamics: This work will allow me to extract valuable results concerning the difference between GR and its modifications in such extreme conditions as in the presence of a black hole. It will also shed more light on black hole thermodynamics which is widely believed that it will provide us with an understanding of gravity at the microscopic level. Evolution of the Universe: I will extract from modified gravity models in general, and from my recent model in particular, the theoretical parameters necessary to be confronted with observations of the sky. This work will tell us more about how to (or not to) modify GR. I will then compare those results with what is found using thermodynamics-based cosmology for a better understanding of the latter. Main benefits: By contributing to a better understanding of black holes and the beginning of the Universe, this work will help shed light on the origins of the Universe and its evolution, as well as provide specific signatures about the fundamental physics of black holes that might be observed by the recent Event Horizon Telescope, in which the University of Waterloo and the Perimeter Institute for Theoretical Physics are taking part, scheduled to give its first images of the giant black hole at the center of our galaxy in 2017.

工作的性质： 该计划的目的是更好地理解重力，黑洞，开始以及宇宙的演变。黑洞是时空的区域，物质是如此稠密，以至于根据爱因斯坦的一般相对论（GR）（我们今天拥有的最佳重力理论）在时空形成孔。我将使用一种理论家最喜欢的工具（称为时空形象映射）来更仔细地研究黑洞的演变，以研究时空。该工具包括更改事件的长度和持续时间，而无需更改该事件的坐标。由于热力学和黑洞的力学是通过使用这种宝贵的理论工具来研究后者的，因此我将为前者带来更多的光线。 另一方面，最近观察到宇宙微波背景（CMB）（填充天空的热辐射）的精确度提高，提供了一种珍贵的工具，可用于测试与GR相差的任何重力模型。我将对我最近的修改重力模型（（（变化的功率）law型号）进行调查，并与天空中的最新数据对抗。最后，最近在重力物理学方面非常活跃的研究是使用热力学来获得宇宙的动力学。我将扩展我对该主题的先前研究，以获得宇宙学和修改后的重力理论之间的联系，以提供两者的所有可能的理论约束。 研究的重要性： 这项工作将有助于我们对黑洞的理解，以及我们对宇宙及其进化的理解。 预期结果： 时空热力学：这项工作将使我能够在极端条件下（如黑洞存在）提取有关GR及其修饰之间差异的有价值的结果。它还将对黑洞热力学有更多的启示，这被广泛认为，它将为我们提供对显微镜水平的重力的理解。 宇宙的演变：我将从一般的重力模型中提取，尤其是从我最近的模型中提取，即面对天空观察所必需的理论参数。这项工作将告诉我们更多有关如何（或不）修改GR的信息。然后，我将将这些结果与使用基于热力学的宇宙学的发现的结果进行比较，以更好地理解后者。 主要好处： 通过有助于更好地了解黑洞和宇宙的开始，这项工作将有助于阐明宇宙的起源及其进化的起源，并提供有关黑洞基本物理的特定签名，这些签名可能是最近事件视野远程镜头可能会观察到的，这是在该地平线上，在该望远平上，在该望远镜中，在该望远镜中，在该望远镜的中心和近距离的一部分是在该中心的一部分，以一定程度地表现出一定的图像，以一定程度地符合特定的一部分，以一定程度地符合特定的一部分，以使特定的一部分符合特定的一部分。我们的银河系在2017年。