报告人：刘超博士

  澳大利亚莫纳什大学(Monash University)

报告题目：Cosmological Newtonian limits on large scales

报告时间： 2017年9月19日下午15:40

报告地点：海韵数理楼661

内容摘要：In this talk, I will rigorously answer one basic question in cosmological simulation: on what space and time scales Newtonian cosmological simulations can be trusted to approximate relativistic cosmologies? We resolve this question under a small initial data condition. Informally, we establish the initial data set in the meaning of cosmological scale which solves constraint equations (with the help of a new tool which we call it the generalized Yukawa potential operator) and construct the existence of 1-parameter families of -dependent solutions to Einstein-Euler system with positive cosmological constant Λ > 0 that: (i) are defined for (0,) for some fixed constant > 0, (ii) exist globally on (t,) ∈ [0,+∞), (iii) converge, in a suitable sense, as  0 to solutions of the cosmological Poison-Euler equations of Newtonian gravity, and (iv) are small, non-linear perturbations of the FLRW fluid solutions (via conformal singular formulation of Einstein-Euler system). This talk originates from a joint work with Todd Oliynyk..

报告人简介：刘超，澳大利亚莫纳什大学(Monash University)博士。主要研究兴趣：利用非线性偏微分方程理论及几何分析方法探索大尺度宇宙的发展中的相关问题。具体的，研究牛顿理论与广义相对论的差异问题（即牛顿极限问题），这是物理学中牛顿极限方法和后牛顿展开方法的重要基石。近三年的主要工作：基于FLRW微扰模型，证明宇宙的长时间行为。严格的证明了牛顿理论与广义相对论的差异在长时间以后非常小。考虑引力耦合物质场（如Yang-Mills场，理想流体场）时，任意De Sitter时空的整体稳定性。

学院联系人：王金花助理教授

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