A SINGULARITY-FREE COSMOLOGICAL MODEL WITH A CONFORMALLY COUPLED SCALAR FIELD

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1994-06-20

Author

BAYIN, SS
COOPERSTOCK, FI
FARAONI, V

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We explore the possibility of describing our universe with a singularity-free, closed, spatially homogeneous and isotropic cosmological model, using only general relativity and a suitable equation of state which produces an inflationary era. A phase transition to a radiation-dominated era occurs as a consequence of boundary conditions expressing the assumption that the temperature cannot exceed the Planck value. We find that over a broad range of initial conditions, the predicted value of the Hubble parameter is approximately 47 km s-1 Mpc-1. Inflation is driven by a scalar field, which must be conformally coupled to the curvature if the Einstein equivalence principle has to be satisfied. The form of the scalar field potential is derived, instead of being assumed a priori.

Subject Keywords

Space and Planetary Science, Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/66525

Journal

ASTROPHYSICAL JOURNAL

DOI

https://doi.org/10.1086/174256

Collections

Department of Physics, Article

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Citation Formats

S. BAYIN, F. COOPERSTOCK, and V. FARAONI, “A SINGULARITY-FREE COSMOLOGICAL MODEL WITH A CONFORMALLY COUPLED SCALAR FIELD,” ASTROPHYSICAL JOURNAL, pp. 439–446, 1994, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66525.