Modified cosmology from extended entropy with varying exponent
Modified cosmology from extended entropy with varying exponent
复制标题
DOI：
10.1140/epjc/s10052-019-6740-5
复制
发表时间：
2019-03-16
影响因子：
4.4
通讯作者：
Saridakis, Emmanuel N.
中科院分区：
文献类型：
--
作者：
Nojiri, Shin'ichi;Odintsov, Sergei D.;Saridakis, Emmanuel N.
我们提出了一个修改后的宇宙学方案，从应用非广延热力学与变化的指数。我们提取修改后的弗里德曼方程，其中包含新的条款量化的非广泛的指数，拥有标准的CDM宇宙学作为一个子例。关于宇宙演化的后期，我们得到了一个有效的暗能量部门，我们表明，我们可以获得通常的热历史，连续序列的物质和暗能量的时代，与有效的暗能量状态方程参数是在精华或幻影制度。这个场景有趣的特点是，即使显式宇宙学常数被设置为零，也可以获得上述行为，即它们纯粹来自额外项。此外，我们面对的Ia型超新星和哈勃参数观测数据的模型，我们表明，协议是非常好的。关于早期宇宙，我们得到暴胀deSitter解决方案，这是由一个有效的宇宙学常数，其中包括新的条款的非广延热力学驱动。这种有效的筛选可以用相同的参数选择提供对膨胀和后期加速的描述，这是一个显著的优点。
We present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. We extract the modified Friedmann equations, which contain new terms quantified by the non-extensive exponent, possessing standard CDM cosmology as a subcase. Concerning the universe evolution at late times we obtain an effective dark energy sector, and we show that we can acquire the usual thermal history, with the successive sequence of matter and dark-energy epochs, with the effective dark-energy equation-of-state parameter being in the quintessence or in the phantom regime. The interesting feature of the scenario is that the above behaviors can be obtained even if the explicit cosmological constant is set to zero, namely they arise purely from the extra terms. Additionally, we confront the model with Supernovae type Ia and Hubble parameter observational data, and we show that the agreement is very good. Concerning the early-time universe we obtain inflationary deSitter solutions, which are driven by an effective cosmological constant that includes the new terms of non-extensive thermodynamics. This effective screening can provide a description of both inflation and late-time acceleration with the same parameter choices, which is a significant advantage.