论文标题
$λCDM$定期宇宙学
$ΛCDM$ periodic cosmology
论文作者
论文摘要
我们研究了定期重复重复的一些$λCDM$扩展的宇宙扩展的可能性，并由某些通胀和辐射占主导的阶段隔开。这种所谓的$λCDM$定期宇宙学是由于通货膨胀和当前阶段加速扩张的可能性是由于相同的暗能量所致。然后，在显示物质密度参数$ω_m$相对于辐射$ω_r$的相位变化的相空间中，曲线$ω_m（ω_r）$看起来像是宇宙可以永远贯穿的封闭轨迹。在这种情况下，$λCDM$相位的扩展加速度的结束是新通货膨胀阶段的开始。我们表明，这种情况意味着物质和/或辐射与暗能量的耦合。我们认为这些$λCDM$周期性模型中最简单的是，即与辐射相结合的真空能量。从物质统治阶段到今天，它的行为就像$λCDM$模型，然后是通货膨胀阶段。但是，在辐射中突然而快速的腐烂会定期结束膨胀加速度。这导致在新的$λCDM$类型扩展之前，以辐射为主的宇宙。该模型使用Markov Chain Monte Carlo模拟使用超新星，哈勃扩展，BAO和CMB数据来限制，并拟合数据以及$λCDM$。
We examine the possibility that Universe expansion be made of some $ΛCDM$ expansions repeating periodically, separated by some inflation and radiation dominated phases. This so-called $ΛCDM$ periodic cosmology is motivated by the possibility that inflation and the present phase of accelerated expansion be due to the same dark energy. Then, in a phase space showing the variation of matter density parameter $Ω_m$ with respect to this of the radiation $Ω_r$, the curve $Ω_m(Ω_r)$ looks like a closed trajectory that Universe could run through forever. In this case, the end of the expansion acceleration of the $ΛCDM$ phase is the beginning of a new inflation phase. We show that such a scenario implies the coupling of matter and/or radiation to dark energy. We consider the simplest of these $ΛCDM$ periodic models i.e. a vacuum energy coupled to radiation. From matter domination phase to today, it behaves like a $ΛCDM$ model, then followed by an inflation phase. But a sudden and fast decay of the dark energy into radiation periodically ends the expansion acceleration. This leads to a radiation dominated Universe preceding a new $ΛCDM$ type expansion. The model is constrained with Markov Chain Monte Carlo simulations using supernovae, Hubble expansion, BAO and CMB data and fits the data as well as the $ΛCDM$ one.
