论文标题
非单明的早期粘性宇宙学模型
A non-singular early-time viscous cosmological model
论文作者
论文摘要
在本文中，我们研究了一种被称为软杆爆炸的非单一早期粘性宇宙学模型的热力学和数学一致性，该模型以前在[N. Cruz，E。González和J. Jovel，物理。修订版D \ textbf {105}，024047（2022）]。该模型代表了一个平坦的同质和各向同性宇宙，充满了耗散辐射流体和宇宙常数$λ$，在Eckart理论的框架内，该宇宙$λ$很小，但不容易忽略。特别是，我们讨论了解决方案在满足以下三个条件方面的能力：（i）在Eckart的非完美流体理论中假定的近平衡条件，（ii）在小扰动下解决方案的数学稳定性，以及（iii）熵产生的正面性。我们发现，这种粘性模型可以描述$λ$ CDM型号的辐射统治时代，同时满足了对庞大的粘性系数$ξ_{0} $的单一约束所提到的三种条件，此外，这种非辛基模型还发现了无限的无限型在无限内的无限型，而无限型的无限密度则是无限内部的infinity the Infinity Hotopy。
In this paper, we study the thermodynamical and mathematical consistencies for a non-singular early-time viscous cosmological model known as soft-Big Bang, which was previously found in [N. Cruz, E. González, and J. Jovel, Phys. Rev. D \textbf{105}, 024047 (2022)]. This model represents a flat homogeneous and isotropic universe filled with a dissipative radiation fluid and a cosmological constant $Λ$, which is small but not negligible, in the framework of Eckart's theory. In particular, we discuss the capability of the solution in the fulfillment of the three following conditions: (i) the near equilibrium condition, which is assumed in Eckart's theory of non-perfect fluids, (ii) the mathematical stability of the solution under small perturbations, and (iii) the positiveness of the entropy production. We have found that this viscous model can describe the radiation domination era of the $Λ$CDM model and, at the same time, fulfill the three conditions mentioned by the fulfillment of a single constraint on the bulk viscous coefficient $ξ_{0}$, finding also that this non-singular model has a positive energy density in the infinity past which is infinity hotter with a constant entropy.
