Generalized equations of state and regular universes

19th Chilean Physics Symposium 2014

Contreras, F.^1 ; Cruz, N.^2 ; González, E.^2

Departamento de Matemátiea y Cieneia de la Computación, Universidad de Santiago de Chile, Las Sophoras 173, Santiago, Chile^1

Departamento de Físiea, Universidad de Santiago de Chile, Avenida Ecuador 3493, Santiago, Chile^2

关键词: Generalized Equations;    Matter field;    Regular solution;    Singular solutions;    Time evolutions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/720/1/012014/pdf
DOI  :  10.1088/1742-6596/720/1/012014

来源: IOP

【 摘 要 】

We found non singular solutions for universes filled with a fluid which obey a Generalized Equation of State of the form P(ρ) = - Aρ + γρλ. An emergent universe is obtained if A =1 and λ = 1/2. If the matter source is reinterpret as that of a scalar matter field with some potential, the corresponding potential is derived. For a closed universe, an exact bounce solution is found for A = 1/3 and the same λ. We also explore how the composition of theses universes ean be interpreted in terms of known fluids. It is of interest to note that accelerated solutions previously found for the late time evolution also represent regular solutions at early times.