年骏  助理教授学术报告

Title: Schwarzian Theory and Cosmological Constant

Speaker: Jun Nian (年骏)

Affiliation: ICTP-AP, University of Chinese Academy of Sciences（中国科学院大学国际理论物理中心（亚太地区））

Time: 16:00-17:00, Friday, 15th May, 2026 (UTC+8, Beijing Time)

Venue: Room 1502, Shing-Tung Yau Center, Sipailou Campus of Southeast University（东南大学四牌楼校区丘成桐中心1502室）

Inviter: Jianfei Xu（许剑飞）

Abstract

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 results of Schwarzian theory 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 Schwarzian theory and its ensemble average to the cosmological constant problem and propose a new approach to resolving it. We will show that this new method yields a theoretical value that exactly matches the observed value. We will also comment on the recent striking results of dark energy observations, such as DESI, and discuss how the theoretical model needs to be adapted. This talk is based on my latest paper, arXiv:2602.17476, and some work in progress.

Speaker

Jun Nian is an assistant professor at the International Centre for Theoretical Physics Asia Pacific (ICTP-AP), University of Chinese Academy of Sciences. He received a Diplom degree from the University of Heidelberg in 2009 and a Ph.D. degree from Stony Brook University in 2015. Before joining ICTP-AP in 2021, he was a postdoctoral fellow at Institut des Hautes Etudes Scientifiques (IHES), the University of Michigan, and the University of Milan. His research interests include quantum field theory, gravity theory, and string theory, with a recent focus on the quantum-gravitational effects in black holes and cosmology.