标题： 各向异性在物质主导的反弹宇宙背景下的功率谱印记 显示英文标题

标题： Imprints of Anisotropy on the Power Spectrum in Matter Dominated Bouncing Universe as Background

摘要： 在本文中，我们旨在研究各向异性对尺度不变功率谱的影响，考虑物质主导坍缩宇宙作为背景，并寻找这种尺度不变性的偏差。 建立此背景后，我们考虑一个无质量标量场，并首先通过微扰方法计算相关性，在这种方法中各向异性背景被近似为由物质主导坍缩宇宙度规表示的有效各向同性度规，其次通过直接数值求解场方程，然后获得对宇宙学感兴趣的模式范围的功率谱。 使用这两种技术，我们得到了功率谱相对于尺度不变性的偏差上限。 我们还计算了更小模式的功率谱，并考察是否可以通过物质反弹情景解释观测到的CMB异常。 显示英文摘要

摘要： In this paper, we aim to investigate the effects of the anisotropy on the scale-invariant power spectrum considering the matter-dominated collapsing universe as background and look for the deviations from this scale invariance. Having set up this background, we consider a massless scalar field and work out the correlations, first by using the perturbative approach in which the anisotropic background is approximated with an effective isotropic metric represented by the metric of matter dominated collapsing universe, second by directly solving the field equation numerically, and then obtain the power spectrum for the range of modes which are of cosmological interest. Using both techniques, we get an upper bound on the deviation in the power spectrum from the scale invariance. We also work out the power spectrum for much smaller modes and look at whether it is possible to explain the observed anomalies in CMB via the matter bounce scenario.