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arXiv · 1210.1010

Brans-Dicke theory of gravity with torsion: A possible solution of the $ω$-problem

Yu-Huei Wu·Chih-Hung Wang
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Abstract

We study the Brans-Dicke theory of gravity in Riemann-Cartan space-times, and obtain general torsion solutions, which are completely determined by Brans-Dicke scalar field $Φ$, in the false vacuum energy dominated epoch. The substitution of the torsion solutions back to our action gives the original Brans-Dicke action with $Φ$-dependent Brans-Dicke parameter $ω(Φ)$. The evolution of $ω(Φ)$ during the inflation is studied and it is found that $ω$ approaches to infinity at the end of inflation. This may solve the $ω$-problem in the extended inflation model.

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Yu-Huei Wu, Chih-Hung Wang. 2012-11-15. Brans-Dicke theory of gravity with torsion: A possible solution of the $ω$-problem. https://doi.org/10.1103/physrevd.86.123519

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