Research in Classical and Quantum Gravity

该项目支持加州大学圣巴巴拉分校的引力物理研究。理论物理中许多最深层次的问题都围绕着爱因斯坦的广义相对论与量子理论的结合展开。由此产生的理论被称为量子引力，需要用来更好地理解宇宙的起源、小尺度上的空间和时间性质，以及黑洞内发生的事情。该奖项支持的研究将使用最新的技术和工具来尝试回答这些根本问题中的一些。这个项目的一个重要部分是对研究生和博士后研究人员进行知识和技术方面的培训，这些知识和技术是理解和发现引力物理的核心。首席调查员会透过一系列的论坛，从公开讲座到告知传媒记者，向广大的听众宣传他们的研究方向和结果。整个社会将受益于增加他们对科学和他们生活的世界的理解。詹姆斯·哈特尔将继续探索量子力学和宇宙学之间的接口。他将致力于将今天用于观测的宇宙无边界量子态的预测扩展到越来越普遍和详细的情况。他将进一步发展宇宙学所必需的量子力学的一般化，并研究量子力学在宇宙学上的扩展。他建议继续完善我们对日常体验的准经典领域的起源的理解，将其作为我们量子宇宙的一个紧急特征。加里·霍洛维茨将研究量子引力全息理论中宇宙奇点附近的物理学。在这些理论中，量子引力自由度可以用低维的非引力理论来等价地描述。霍洛维茨还将探索重力和凝聚态物质之间的联系，这种联系可以用经典的全息术极限来产生。这为研究超导电性等现象提供了新的工具。此外，霍洛维茨还将研究高维黑洞的方方面面。唐·马洛夫将探索经典和量子引力中与黑洞、热力学和熵有关的各种问题。其一是将黑洞是热力学系统的论点推广到更一般的情况。另一项是研究时空中更一般表面的面积可能也与熵有关，以及时空本身可能只因热力学现象而存在。他工作的最后一部分将继续研究一种量子力学现象(所谓的霍金效应)的含义，这种现象会导致黑洞慢慢蒸发，这可能需要我们对基础物理的理解发生重大变化。所有这些工作所采用的方法将主要是解析的，尽管它将辅之以台式计算机上的数值计算。

This project supports research in gravitational physics at the University of California, Santa Barbara. Many of the deepest problems in theoretical physics revolve around combining Einstein's theory of general relativity with quantum theory. The resulting theory is called "quantum gravity" and is needed to better understand the origin of the universe, the nature of space and time on small scales, and what happens inside black holes. The research supported by this award will use the latest techniques and tools to try to answer some of these fundamental problems. An essential part of this project is the training of graduate students and postdoctoral researchers in the knowledge and techniques that are central to understanding and discovery in gravitational physics. Through a range of forums from public lectures, to informing media reporters, the Principal Investigators will disseminate the directions and results of their research to a broad audience. Society at large will benefit by increasing their understanding of science and the world they live in.James Hartle will continue exploring the interface between quantum mechanics and cosmology. He will work on extending the predictions of the no-boundary quantum state of the universe for observations today to increasingly general and detailed situations. He will further develop the generalizations of quantum mechanics that are necessary for cosmology and investigate cosmologically motivated extensions of quantum mechanics. He proposes to continue to refine our understanding of the origin of the quasiclassical realm of every day experience as an emergent feature of our quantum universe. Gary Horowitz will investigate physics near cosmological singularities in holographic theories of quantum gravity. These are theories in which quantum gravitational degrees of freedom are equivalently described by a lower dimensional nongravitational theory. Horowitz will also explore connections between gravity and condensed matter that can arise using a classical limit of holography. This provides a new tool for the study of superconductivity and other phenomena. In addition, Horowitz will investigate aspects of higher dimensional black holes. Don Marolf will explore a variety of issues in classical and quantum gravity related to black holes, thermodynamics, and entropy. One is to extend arguments that black holes are thermodynamic systems to more general situations. Another is to investigate the possibility that the area of more general surfaces in spacetime might also be associated with entropy, and that spacetime itself may exist only due to thermodynamic phenomena. A final part of his work will continue to study implications of a quantum-mechanical phenomenon (the so-called Hawking effect) that causes black holes to slowly evaporate and which may require significant changes in our understanding of fundamental physics. The methods employed for all this work will be primarily analytic, though it will be supplemented with numerical calculations on desktop computers.