论文标题
重新访问单模型重力和$ H_0 $张力的宇宙扩散模型
Revisiting cosmological diffusion models in Unimodular Gravity and the $H_0$ tension
论文作者
论文摘要
在非模块性重力的框架内，我们考虑了暗物质与暗能量之间的非重力相互作用。特别是，我们通过考虑将冷暗物质流体与暗能量分量相结合的扩散模型来描述黑暗扇区中的这种相互作用，在该模型中，后者的形式具有可变的宇宙学“常数”。我们第一次解决了这些模型从辐射主导的时代到今天的宇宙学演变。我们通过分析能量密度参数的宇宙学演化$ω__{CDM} $和$ω_λ$以及Hubble参数的宇宙学演化是如何进行扩散过程的。最后，我们通过使用Planck 2018，SH0ES，Pantheon和H0licow协作的数据来执行统计分析，对扩散参数施加约束。我们发现，在单模型重力框架中，宇宙扩散模型可以缓解$ H_0 $的当前张力。我们还表明，所有扩散模型的未来宇宙学演变都在不将来的奇异性的情况下永恒加速。
Within the framework of Unimodular Gravity, we consider non-gravitational interactions between dark matter and dark energy. Particularly, we describe such interactions in the dark sector by considering diffusion models that couple the cold dark matter fluid with the dark energy component, where the latter has the form of a variable cosmological "constant". For the first time, we solve the cosmological evolution of these models from the radiation dominated era to the present day. We show how the diffusion processes take place by analyzing the cosmological evolution of the energy density parameters $Ω_{cdm}$ and $Ω_Λ$, as well as that of the Hubble parameter. Finally, we perform the statistical analysis, imposing constraints on the diffusion parameters, by using data from Planck 2018, SH0ES, Pantheon, and H0LICOW collaborations. We found that cosmological diffusion models in the framework of Unimodular Gravity can ease the current tension in the value of $H_0$. We also show that the very far future cosmological evolution for all diffusion models is eternally accelerating without future singularities.
