报告题目：Bubble wall velocity from number density current

报 告 人：王少江 (Institute of Theoretical Physics, Chinese Academy of Sciences)

报告时间：2024年10月17日13:30

报告地点：物理楼W105

内容摘要：Cosmological first-order phase transitions (FOPTs) serve as comprehensive probes into our early Universe with associated generations of stochastic gravitational waves and superhorizon curvature perturbations or even primordial black holes. In characterizing the FOPT, phenomenological parameters like transition temperatures, strength factors, bubble separations, and energy budgets can be easily extracted from the macroscopic equilibrium features of the underlying particle physics models except for the terminal wall velocity of the bubble expansion, making it the last key parameter to be determined most difficultly due to the non-equilibrium nature of the microscopic transition model. In this talk, I will introduce our recent work on proposing a new model-independent approach to calculate the bubble wall velocity from the conservation and violation of total number density current.

报告人简介：Shao-Jiang Wang received his PhD in 2018 from the Institute of Theoretical Physics, Chinese Academy of Sciences (ITP-CAS), after that, he became a postdoctoral researcher at Tufts University. In 2021, he came back to ITP-CAS as a Special Research Assistant (Postdoctoral), and later became a Fixed-Term Associate Researcher since 2023. His research interest widely spans over various topics on the meeting-point of cosmology, gravitation, and particle physics. His current focus is on the cosmological first-order phase transition and the Hubble-constant problem.