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arXiv astro-ph/9601034astro-phgr-qchep-th
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混沌混合会促进Ω <1暴胀吗?

Does Chaotic Mixing Facilitate Omega<1 Inflation?

Neil J. Cornish, David N. Spergel, Glenn D. Starkman

摘要:

是的,如果宇宙有紧凑的拓扑结构。暴胀是目前最优雅的解释为什么宇宙是古老的,大的,几乎平坦的,在大尺度上均匀的,在小尺度上结构。暴胀范式的一个弱点是暴胀的初始条件问题:暴胀宇宙一定有些古老,有些大,有些均匀。这些初始条件的要求在Ω < 1暴胀模型中甚至更为严格:如果宇宙没有膨胀到足够扁平的程度,那么它也没有膨胀到足够均匀的程度。一个解决方案是有两个通货膨胀时期。在这里,我们提出了另一种解决暴胀前均匀性问题的方法:如果宇宙是紧凑的,那么在暴胀前时期,有足够的时间使宇宙均匀化,因为混沌混合消除了原始波动。能量密度中的熵被减少为e^(-kappa d),其中kappa是流动的Kolomogorov-Sinai熵,d是流动行进的距离。我们探讨了这种均匀化过程,概述了为什么紧凑的负弯曲的宇宙是最自然的,并结束了生活在这样一个宇宙的影响的讨论。

英文摘要:

Yes, if the universe has compact topology. Inflation is currently the most elegant explanation of why the universe is old, large, nearly flat, homogeneous on large scales and structured on small scales. One of the weaknesses of the inflationary paradigm is the problem of initial conditions for inflation: the pre-inflationary universe must be somewhat old, somewhat large and somewhat homogeneous. These initial condition requirements are even more severe in Omega < 1 inflationary models: if the universe does not inflate enough to appear flat, then it does not inflate enough to appear homogeneous. One solution is to have two inflationary epochs. Here, we propose another solution to the problem of pre-inflationary homogeneity: if the universe is compact, then during the pre-inflationary period, there is sufficient time to homogenize the universe as chaotic mixing smoothes out primordial fluctuations. Gradients in the energy-density are reduced as e^(-kappa d), where kappa is the Kolomogorov-Sinai entropy of the flow, and d is the distance the flow travels. We explore this homogenization process, outline why compact negatively-curved universes are the most natural, and conclude with a discussion of the implications of living in such a universe.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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