Cosmological Modified Gravity Simulations with Massive Sterile Neutrinos

该项目将包括在修正重力（MOND）框架下建立一个大型（bbb100 Mpc）的宇宙学模拟，但辅以11-eV的无菌中微子，以弥补与Lambda冷暗物质（LCDM）宇宙学中相同的总暗能量和物质密度。模拟将建立在现有的无菌中微子+ MOND框架（例如Katz+ 2013）的模拟基础上，该框架获得了有希望的结果。该项目将在修正重力下使用现有的RAMSES代码幻影（Nagesh+ 2021），结合牛顿初始条件，红移约为200，此时MOND效应应该可以忽略不计。在大尺度上，结构的形成将比LCDM更快，而在小尺度上，冷暗物质的缺乏将通过增强的远程引力定律得到补偿。目的是寻找(1)类似于埃尔戈多的大质量星系团对，(2)类似于当地300 Mpc的KBC空洞；这两者都排除了6西格玛显著性以上的LCDM （Haslbauer+ 2020, Asencio+ 2021）。更一般地说，模拟的结果将与一系列观测结果进行比较，例如，在低密度区域（空洞）中，像我们这样的观测者500 Mpc内的星团质量函数。该项目将由赵宏生博士监督，Indranil Banik博士密切指导。它将与波恩的动力学小组合作，该小组长期以来一直对类似问题感兴趣，并有研究人员在类似领域工作。请参阅Banik & Zhao最近的评论（https://arxiv.org/abs/2110.06936）和最近邀请的讲座概述修正重力，请参阅（https://www.youtube.com/watch?v=jL09gRe1q7s）。

This project would involve setting up a large (>100 Mpc) cosmological simulation in the Modified Gravity (MOND) framework, but supplemented with 11-eV sterile neutrinos to make up the same total dark energy and matter density as in the Lambda Cold Dark Matter (LCDM) cosmology.The simulations would build on existing simulations of the sterile neutrino + MOND framework (e.g. Katz+ 2013) that obtained promising results. The project would use the existing Phantom of RAMSES code (Nagesh+ 2021) in Modified Gravity combined with Newtonian initial conditions at a redshift of about 200, when MOND effects should be negligible. Structure formation would proceed more rapidly than in LCDM on large scales, while on small scales the lack of cold dark matter would be compensated by an enhanced long range gravity law.The aim would be to look for (1) analogues to the El Gordo-like massive galaxy cluster pair and (2) analogues to the local 300 Mpc KBC void; both of these rule out LCDM above 6-sigma significance (Haslbauer+ 2020, Asencio+ 2021). More generally, the results of the simulations would be compared with a range of observations, e.g., the cluster mass function within 500 Mpc of observers like us in a low-density region (void).The project would be supervised by Dr Hongsheng Zhao and closely guided by Dr Indranil Banik. It would be in collaboration with the dynamics group in Bonn, which has long been interested in similar problems and has researchers working on a similar area. See a recent review by Banik & Zhao (https://arxiv.org/abs/2110.06936) and a recent invited lecture overviewing Modified Gravity, see (https://www.youtube.com/watch?v=jL09gRe1q7s).