报告题目:Quantum-Gravity Hamiltonian

报告人：张聪

报告时间：2021年05月07日（周五）上午10:00

报告地点：理学楼二楼师生活动中心

摘要 (Abstract): Given the Loop-Quantum-Gravity (LQG) non-graph-changing Hamiltonian ⟨H[N]⟩the coherent state expectation value.⟨H[N]⟩ admits an semiclassical expansion in l_p^2. In this paper, we compute explicitly the expansion of ⟨H[N]⟩ on the cubic graph to the linear order in l_p^2, when the coherent state is peaked at the homogeneous and isotropic data of cosmology. In our computation, a powerful algorithm is developed to overcome the complexity in computing ⟨H[N]⟩ In particular, some key innovations in our algorithm substantially reduce the computational complexity in the Lorentzian part of ⟨H[N]⟩. In addition, some effects in cosmology from the quantum correction in ⟨H[N]⟩ are discussed at the end of this paper.

报告人简介(Bio) : 张聪，波兰华沙大学物理系博士后。2013年本科毕业于北京师范大学天文系，2019年博士毕业于北京师范大学物理系。之后赴华沙大学物理系进行博士后研究工作。目前主要从事圈量子引力，圈量子宇宙学以及圈量子黑洞的研究，在该方向发表论文10余篇。

邀   请   人  ：朱涛 教授