报告人：王东刚博士后（剑桥大学应用数学和理论物理系）

题目：The Cosmological Bootstrap: Theory and Observations（宇宙学自举：理论与观测）

时间：2024年6月28日（周五）10:00

地点：理工楼1226

腾讯ID：812704299

联系人：刘玉孝

报告摘要：

Our understanding of the primordial Universe largely depends on the information from spatial correlations of matter distributions. Recently, the advances of the "cosmological bootstrap" program offer new perspectives and powerful tools to study these cosmological correlators. In this talk, I will first review the developments of this exciting new direction. Then I will apply the bootstrap method to systematically classify the leading observational target—primordial non-Gaussianities (bispectrum) from cosmic inflation. For the first time, we derive a complete set of scalar bispectra with analytical shapes and large signals, incorporating three leading scenarios: single field inflation, cosmological collider physics, and multi-field inflation. Remarkably, the bootstrap analysis predict novel phenomenologies, which are testable even in today’s observations. In the end, guided by the theoretical studies, I will present a comprehensive data analysis of these predictions using the latest CMB observation from Planck satellite. As the first attempt, we bridge the gap between theories and observations, and demonstrate how the cosmological bootstrap paves the way towards the discovery of new high energy physics in the very early Universe.

我们目前对极早期宇宙的理解在很大程度上依赖于宇宙尺度物质分布上的空间关联信息。近年来，”宇宙学自举”（The Cosmological Bootstrap）的提出和快速发展为研究宇宙学关联函数提供了全新视角和强大理论工具。在此类研究中，我们由理论自洽性出发，侧重于构建对宇宙”没有时间“的描述。在此次报告中，我会首先回顾这一研究方向的最新进展。然后，我会采用自举法来对暴涨理论的核心预言——原初非高斯性提供一个系统的分类。我们的研究包含三类主流暴胀理论：单场、多场和宇宙学对撞机。有趣的是，自举法给出了完整的解析结果并包含了全新的唯象预言。最后，我会介绍近期对自举法给出的预言进行的首次观测检验。与CMB专家合作，我们在Planck卫星的数据中对这些原初非高斯性信号进行了系统的搜索。将理论和观测相结合，此项研究为未来在极早期宇宙中探寻高能新物理做好了准备。

报告人简介：

Dong-Gang Wang is a Rubicon Postdoctoral Fellow at the Department of Applied Mathematics and Theoretical Physics in the University of Cambridge, UK. Before that, he did his PhD in Leiden University in the Netherlands as a de Sitter Fellow from 2016 to 2020. Before that, he got his master degree from USTC in 2016. His research focuses on theoretical cosmology, in particular on an emerging interdisciplinary direction that applies new theoretical methods of high energy physics in studies of the primordial Universe.

王东刚博士是剑桥大学应用数学和理论物理系的Rubicon高级博后学者。在此之前，王东刚作为de Sitter学者于2020年博士毕业于荷兰莱顿大学，2016年硕士毕业于中国科学技术大学天文学系。王东刚博士的研究兴趣是宇宙暴胀理论，近期侧重于宇宙学和高能理论物理交叉的方向，包括宇宙学自举、德西特时空量子场论、原初非高斯性等。