报告人：刘建良 博士（东莞理工学院）

时间：2019-11-16 上午10:00

地点：数学系实验室

摘要：The quasi-local energy (QLE) under 4D isometric matching reference depends on two free functions on a spacelike closed two surface. One free function corresponds to the isometric embedding of a closed two surface and the other free choice also depends on the boost of the timelike displacement vector N on the surface. Consider QLE for the axisymmetric spacetime with the two surface isometric embedding into R^3, the choice of embedding is fixed and the remaining free choice corresponds to the boost of N. We analyze QLE along timelike geodesics normal to the two surface generated by N (as a freely falling observer on the surface) and found that for Kerr spacetime, the integrand k_0-λk is in the form o(ϵ^2) with a=rϵ and it is negative at the pole. For the application on Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology, QLE along timelike geodesics is proportional to the spatial curvature k which is positive for closed universe, zero for flat universe and negative for open universe.

报告人简介：刘建良，东莞理工学院计算机科学与技术学院讲师。台湾中央大学博士。主要从事广义相对论中拟局域能量的研究。研究工作主要发表于Classical and Quantum Gravity, Physical Review D等国际权威杂志。