Nonlinear dynamics in the Einstein-Gauss-Bonnet gravity

作     者：Hisa-aki Shinkai Takashi Torii 

作者机构：Department of Information Systems Faculty of Information Science & Technology Osaka Institute of Technology Kitayama Hirakata City Osaka 573-0196 Japan Department of System Design Faculty of Robotics & Design Osaka Institute of Technology Kita-ku Osaka City Osaka 530-8568 Japan 

出 版 物：《Physical Review D》 (Phy. Rev. D)

年 卷 期：2017年第96卷第4期

页      面：044009-044009页

核心收录：

基　　金：Japan Society for the Promotion of Science, JSPS, (25400277) Ministry of Education, Culture, Sports, Science and Technology, MEXT, (17H06357, 17H06358) 

主　　题：Alternative gravity theories General relativity Gravity in dimensions other than four Singularities In general relativity 

摘      要：We numerically investigated how nonlinear dynamics depends on the dimensionality and on the higher-order curvature corrections in the form of Gauss-Bonnet (GB) terms. We especially monitored the processes of appearances of a singularity (or black hole) in two models: (i) a perturbed wormhole throat in spherically symmetric space-time, and (ii) colliding scalar pulses in plane-symmetric space-time. We used a dual-null formulation for evolving the field equations, which enables us to locate the trapping horizons directly, and also enables us to follow close to the large-curvature region due to its causal integrating scheme. We observed that the fate of a perturbed wormhole is either a black hole or an expanding throat depending on the total energy of the structure, and its threshold depends on the coupling constant of the GB terms (αGB). We also observed that a collision of large scalar pulses will produce a large-curvature region, of which the magnitude also depends on αGB. For both models, the normal corrections (αGB0) work for avoiding the appearance of singularity, although it is inevitable. We also found that in the critical situation for forming a black hole, the existence of the trapped region in the Einstein-GB gravity does not directly indicate the formation of a black hole.