Research On Fluctuations of Gravity and Quantum Fields

本项目将对时空量子涨落的几个方面及相关问题进行理论研究。任何量子引力理论的一个关键问题是理解这些涨落及其物理效应。一个将是早期宇宙中量子能量密度波动的影响，特别是在暴胀宇宙学的背景下。PI和他的合作者先前的研究表明，这些影响可能比人们天真地猜测的要大，并且可能大到足以引起今天可观察到的影响。一个相关的课题是研究量子能量密度波动的概率分布。更好地理解这种分布，特别是描述罕见但大波动的部分，可以应用于量子理论和宇宙学中的几个问题。该项目的其他方面将包括寻找量子引力波动的长期影响，即在宇宙历史中积累的影响。如果这种效应存在并且可以被检测到，它将带来重要的见解。该项目还将涉及寻找实验室实验，以探测模拟系统中的负能量和光锥波动等影响。预计该项目将对其他科学领域、教育和技术领域产生更广泛的影响。这项工作的见解和技术可能在正在研究的物理的特定子领域之外有用。预计该项目将通过研究生和主要教学机构教员的参与来促进教育。它还应该提供可以用来向不同教育水平的学生解释量子理论和相对论的一些概念的例子。该项目的一些研究结果可能对其他物理领域有用，如原子物理学和凝聚态物理学，并可能最终具有技术应用。

This project will entail theoretical studies of several aspects of quantum fluctuations of spacetime and related issues. A key problem in any quantum theory of gravity is understanding these fluctuations and their physical effects. One will be the effects of quantum energy density fluctuation in the early universe, especially in the context of inflationary cosmology. Previous studies by the PI and his collaborators indicate that these effects may be larger than one would have naively guessed, and possibly large enough to cause observable effects today. A related topic is the study of the probability distribution for quantum energy density fluctuations. A better understanding of this distribution, especially the part which describes rare but large fluctuations, can have applications to several questions in quantum theory and cosmology. Other aspects of the project will include a search for secular effects from quantum gravity fluctuations, that is, effects which can accumulate over the history of the universe. If such effects exist and can be detected, it would lead to significant insights. The project will also involve a search for laboratory experiments to detect such effects as negative energy and lightcone fluctuations in analog systems.This project is expected to have a broader impact through possible benefits to other fields of science, to education, and to technology. The insights and techniques of this work may be useful outside of the specific subfields of physics being investigated. The project is expected to further education through the involvement of graduate students and of faculty at primarily teaching institutions. It should also produce examples which can be used to explain some of the concepts of quantum theory and relativity to students on a variety of educational levels. The results of some of the investigations in this project may be useful in other fields of physics, such as atomic physics and condensed matter physics, and might eventually have technological applications.