论文标题
宇宙学扰动：没有玻尔兹曼等级的非冷遗物
Cosmological perturbations: non-cold relics without the Boltzmann hierarchy
论文作者
论文摘要
我们提出了一种宇宙学扰动理论的表述，其中玻尔兹曼层的层次结构被进化的中微子相位空间分布被积分所取代，积分可以通过快速的傅立叶变换轻松评估。然后，对系统其余部分（暗物质，光子，重子）的微分方程的同时评估将使用迭代方案迅速收敛。该公式对于大型中微子特别有力，其中有效的相空间是三维而不是二维的，甚至对于三种不同的中微子质量特征态。因此，它有可能显着加快宇宙学扰动计算的计算时间。这种方法也应适用于具有其他非冷碰撞文物的模型。
We present a formulation of cosmological perturbation theory where the Boltzmann hierarchies that evolve the neutrino phase-space distributions are replaced by integrals that can be evaluated easily with fast Fourier transforms. The simultaneous evaluation of these integrals combined with the differential equations for the rest of the system (dark matter, photons, baryons) are then solved with an iterative scheme that converges quickly. The formulation is particularly powerful for massive neutrinos, where the effective phase space is three-dimensional rather than two-dimensional, and even moreso for three different neutrino mass eigenstates. Therefore, it has the potential to significantly speed up the computation times of cosmological-perturbation calculations. This approach should also be applicable to models with other non-cold collisionless relics.
