Numerical and perturbative computations of the fuzzy dark matter model
Numerical and perturbative computations of the fuzzy dark matter model
复制标题
模糊暗物质模型的数值和微扰计算
DOI：
10.1103/physrevd.99.063509
复制
发表时间：
2018
影响因子：
5
通讯作者：
G. Bryan
中科院分区：
文献类型：
--
作者：
Xinyu Li;L. Hui;G. Bryan
我们研究模糊暗物质（FDM）模型中的非线性结构的形成，使用数值和微扰技术。在数值方面，我们研究的优点和局限性的薛定谔-泊松求解器（波制定）与流体动力学求解器（马德隆制定）。我们还进行了微扰计算的单圈质量功率谱。我们发现，（1）在许多情况下，流体动力学求解器能够产生预期的干涉图案，但它失败的破坏性干涉导致密度消失，这通常发生在非线性状态。(2)Schrodinger-Poisson解算器在所有测试用例中都能很好地工作，但它在分辨率上要求很高：必须解决小的德布罗意布罗意尺度以获得大尺度上的正确动力学。(3)我们比较了从微扰理论对从薛定谔-泊松求解器的质量功率谱，并发现在轻度非线性政权良好的协议。与流体微扰理论相比，波动微扰理论的适用范围更为有限。(4)作为一个应用程序，我们比较莱曼α森林通量功率谱从薛定谔-泊松求解器与一个从N体模拟（这是经常被用作一种近似方法，使FDM的预测）。在红移5处，从相同的初始条件开始，只要FDM质量超过2 × 10^{-23}$ eV，两者在观测相关尺度上的一致性就超过10%。
We investigate nonlinear structure formation in the fuzzy dark matter (FDM) model using both numerical and perturbative techniques. On the numerical side, we examine the virtues and limitations of a Schrodinger-Poisson solver (wave formulation) versus a fluid dynamics solver (Madelung formulation). We also carry out a perturbative computation of the one-loop mass power spectrum. We find that (1) in many cases, the fluid dynamics solver is capable of producing the expected interference patterns, but it fails where destructive interference causes the density to vanish which generally occurs in the nonlinear regime. (2) The Schrodinger-Poisson solver works well in all test cases, but it is demanding in resolution: one must resolve the small de Broglie scale to obtain the correct dynamics on large scales. (3) We compare the mass power spectrum from perturbation theory against that from the Schrodinger-Poisson solver, and find good agreement in the mildly nonlinear regime. Compared with fluid perturbation theory, wave perturbation theory has a more limited range of validity. (4) As an application, we compare the Lyman-alpha forest flux power spectrum obtained from the Schrodinger-Poisson solver versus one from an N-body simulation (which is often used as an approximate method to make predictions for FDM). At redshift 5, the two, starting from the same initial condition, agree to better than 10 % on observationally relevant scales as long as the FDM mass exceeds $2 \times 10^{-23}$ eV.