论文标题
与各向同性潮汐力的空间平坦宇宙
Spatially flat universes with isotropic tidal forces
论文作者
论文摘要
我们研究了在爱因斯坦方程下提交给各向同性潮汐力和绝热扩张的空间平坦宇宙的动力学。令人惊讶的是，在我们假设强大的能量状况上，高大哈勃各向异性的趋势开始出现，这种特征在辐射时代占主导地位，在僵硬的物质方面更加严格。我们介绍了参数B，该参数B测量了哈勃各向异性和尺度因子的相对变化，并使用它来表明，只要我们假设宇宙已经通过膨胀时期，并且根据宇宙的无头发定理，则必须保持小时。因此，我们有一类模型，向我们展示了一种简单明了的方式，即FLRW宇宙的不稳定性，各向同性概念的外交性，以及它们仍然可以与宇宙学的标准模型保持一致。
We investigate the dynamics of the spatially flat universes submitted to isotropic tidal forces and adiabatic expansion under Einstein's equations. Surprisingly, the tendency to a high Hubble anisotropy at late times starts to appear as far as we assume the strong energy condition, a characteristic which becomes dominant in the radiation era and even more stringent under a stiff matter regime. We introduce the parameter b which measures the relative change in the magnitudes of the Hubble anisotropy and the scale factor and use it to show that the anisotropies must be kept small as long as we assume the Universe has passed through an inflationary period, in accordance with the cosmic no-hair theorem. Hence, we have a class of models that shows us a simple and straightforward way the instability of the FLRW universes, the furtiveness of the isotropy concept, and how they can still be consistent with the standard model of Cosmology as far as we assume the occurrence of an inflationary early period.
