Research in Classical and Quantum Gravity

该奖项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的性质，以及黑洞内部发生的事情。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。该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，这些知识和技术对理解和发现引力物理至关重要。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·霍洛维茨将研究经典引力和量子引力的各种主题，重点是奇点和时空的起源。他将探索经典奇点是可见的，还是必须总是隐藏在事件视界之后。他还将研究最近发现的潜在可见奇点和带电物质之间的联系。此外，霍洛维茨还将研究时空几何是如何从量子引力的全息理论中产生的。他将考虑量子纠缠的卷曲，但也会基于无穷远处的特殊边界横截面来追求一个新的方向。唐·马洛夫将探索经典和量子引力中的各种问题，通常与黑洞、热力学和熵有关。虽然已经有很多证据表明黑洞在某种意义上是热系统(其熵与其表面积成正比)，尽管这有望为物理学提供深刻而基本的教训，但这一论点尚未完全概括。Marolf将探索所需的扩展和由此产生的影响。他工作的另一部分试图更深入地理解所谓的引力全息描述，即动态时空中的现象实际上相当于一个看似非常不同的非引力系统的量子物理。在这方面，Marolf特别感兴趣的是理解词典，该词典允许人们将黑洞内的物理转换为非引力公式的语言。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award 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 the 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 a variety of topics in classical and quantum gravity, focussing on singularities and the origin of spacetime. He will explore whether classical singularities can be visible, or must always be hidden behind event horizons. He will also examine a recently discovered connection between potential visible singularities and charged matter. In addition, Horowitz will study how spacetime geometry emerges from a holographic theory of quantum gravity. He will consider the roll of quantum entanglement, but also pursue a new direction based on special cross-sections of the boundary at infinity. Don Marolf will explore a variety of issues in classical and quantum gravity generally related to black holes, thermodynamics, and entropy. While there is already much evidence that black holes are in some sense thermal systems (with entropy proportional to their surface area), and while this is expected to hold deep and fundamental lessons for physics, the argument has not yet been made in complete generality. Marolf will explore the required extensions and the resulting implications. Another part of his work seeks to more deeply understand so-called holographic descriptions of gravity, where phenomena in a dynamical spacetime are in fact equivalent to the quantum physics of a seemingly very different non-gravitating system. In this regard, Marolf is particularly interested in understanding the dictionary that allows one to translate physics inside black holes into the language of the non-gravitating formulation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.