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Brans-Dicke Cosmology Corrected for a Quantum Effect due to the Scalar-Matter Coupling

Yasunori Fujii
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Abstract

Cosmological solutions of the Brans-Dicke theory are investigated by including a quantum effect coming from 1-loop correction of matter fields that couple to the scalar field. As the most serious result we face a cosmological ``constant'' in the original conformal frame which is shown to be ``physical'' after a careful analysis of the time variable employed in any of the conventional approaches. We find an ``attractor'' solution featuring no expansion during the radiation-dominated eras. To evade this unacceptable consequence, we suggest to modify one of the fundamental premises of the model, rendering the scalar field almost ``invisible.''

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Yasunori Fujii. 1996-09-17. Brans-Dicke Cosmology Corrected for a Quantum Effect due to the Scalar-Matter Coupling. https://arxiv.org/abs/gr-qc/9609044

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