String Theory as Quantum Gravity IV

作为量子引力的弦理论 IV

• 批准号: SAPIN-2015-00034
• 负责人: Peet, Amanda
• 金额: $ 3.28万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=689112
• 关键词: String; Theory; Quantum; Gravity; IV

My long term goal is to understand how to reconcile Einstein's theory of gravity with quantum mechanics, with a special interest in the physics of black holes. To investigate this, I use string theory, which is currently the best-developed theoretical framework available for doing computations of interest in quantum gravitational physics. String theory is an appropriate toolset because it manages to encompass both the smooth spacetime geometry of gravity on large scales and the probabilistic uncertainty of quantum mechanics on small scales. Two related advances in string theory technology in the past nineteen years have helped make my long term goal more accessible. ***   The first advance was the discovery of higher-dimensional objects known as D-branes in string theory, which co-exist alongside the one-dimensional fundamental strings. D-branes are versatile theoretical beasts, because they gravitate and carry charges. Applications were quickly discovered which shed new light on longstanding fundamental questions about the physics of black holes. E.g. string technologies applied to a variety of special higher-dimensional black holes enabled the first quantitative derivation from first principles of the Bekenstein-Hawking entropy, a quantity akin to disorganization which encodes the large number of ways a black hole could be formed in gravitational collapse. String theory models with many moving parts also have the potential to address another more complicated question: Hawking's famous black hole information paradox, which concerns the fate of information that falls into black holes. Much progress has been made, but still more territory remains to be understood. Contributing to developing microscopic string theory models of black hole physics further is one of the twin themes of this research proposal. ***   The second advance was a surprising and powerful new discovery that certain gravitational theories with negative cosmological constant possessing one extra dimension of space can be physically equivalent to certain non-gravitational field theories. This is akin to how holograms work: you can reconstruct the whole three-dimensional image from only the two-dimensional hologram. String theory holography, also known as the AdS/CFT correspondence, has been applied to a wide variety of theoretical problems of interest for string and particle theorists, and has also produced partial progress on modelling aspects of the quark-gluon plasma and condensed matter phenomena. It has sparked discovery of new types of gravitational spacetimes, and strengthened the conceptual connections between information theoretic entanglement and the geometry of spacetime. Contributing to developing holography is the other main theme of this proposal.**

我的长期目标是理解如何调和爱因斯坦的引力理论和量子力学，以及对黑洞物理学的特殊兴趣。为了研究这个问题，我使用了弦理论，这是目前在量子引力物理中进行计算的最好的理论框架。弦理论是一个合适的工具集，因为它成功地涵盖了大尺度上引力的光滑时空几何和小尺度上量子力学的概率不确定性。在过去的19年里，弦理论技术的两个相关进展使我的长期目标更容易实现。***第一个进展是发现了弦理论中被称为d膜的高维物体，它与一维基本弦共存。d膜是多用途的理论巨兽，因为它们具有引力和携带电荷。人们很快发现了一些应用，为长期存在的黑洞物理学基本问题提供了新的线索。例如，将弦技术应用于各种特殊的高维黑洞，可以从贝肯斯坦-霍金熵的第一原理中获得第一个定量推导，贝肯斯坦-霍金熵是一个类似于无序的量，它编码了黑洞在引力坍缩中形成的大量方式。具有许多运动部件的弦理论模型也有可能解决另一个更复杂的问题：霍金著名的黑洞信息悖论，它涉及落入黑洞的信息的命运。已经取得了很大的进展，但仍有更多的领域有待了解。进一步发展黑洞物理的微观弦理论模型是本研究计划的两个主题之一。***第二个进展是一个令人惊讶和强大的新发现，即某些具有负宇宙常数的引力理论具有一个额外的空间维度，可以在物理上等同于某些非引力场理论。这类似于全息图的工作原理：你可以仅从二维全息图重建整个三维图像。弦理论全息，也被称为AdS/CFT对应，已经应用于弦和粒子理论家感兴趣的各种理论问题，并且在夸克-胶子等离子体和凝聚态现象的建模方面也取得了部分进展。它激发了对新型引力时空的发现，并加强了信息理论纠缠与时空几何之间的概念联系。促进全息摄影的发展是本提案的另一个主题