报告题目：Dark Energy and Time Reparametrizations

报告人：年骏 副教授（中国科学院大学 ICTP-AP）

报告时间：2026 年 11 月 12 日（周四）15 : 30-16 : 30

报告地点：北洋园校区 49 教 410 室

报告摘要：

The cosmological constant’s quantum origin is a famous open problem in theoretical physics and cosmology. Its observed value and theoretical prediction exhibit a large 120-order discrepancy. In this talk, we first summarize the current state of research on the cosmological constant problem and review the Schwarzian theory of time reparametrizations in the literature. Inspired by an early work by Gary Gibbons and our recent attempts to solve various formidable problems (e.g., color confinement in SYM, fluid/gravity correspondence at low temperatures, etc.) via the JT gravity/Schwarzian theory duality, we apply the Schwarzian theory of time reparametrizations and its ensemble average to the cosmological constant problem and propose a new approach to resolving it. We will show that this new method, at leading order, yields a theoretical value that exactly matches the observed value of the cosmological constant. However, recent results from dark energy observations (such as DESI) suggest a dynamical dark energy. Starting from the leading-order constant value, we will take into account matter-gravity interactions and develop a more realistic dynamical dark energy model based on time reparametrizations that can fit observational data with comparable precision to other models (e.g., ΛCDM and CPL). We also provide some falsifiable predictions for future more precise observations. This talk is based on my recent paper arXiv:2602.17476 and another upcoming work.

报告人简介：

年骏，中国科学院大学国际理论物理中心（亚太地区）副教授。2009年本硕连读毕业于德国海德堡大学，2015年在美国纽约州立大学石溪分校获得博士学位。2015～2021年先后在法国高等科学研究院、美国密歇根大学、意大利米兰大学任博士后研究员。2021年入职中国科学院大学国际理论物理中心（亚太地区）。研究领域包括量子场论、引力理论、弦论，近期主要关注黑洞物理和宇宙学中的量子引力效应。