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Symmetric vacuum scalar--tensor cosmology

James E. Lidsey
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Abstract

The existence of point symmetries in the cosmological field equations of generalized vacuum scalar--tensor theories is considered within the context of the spatially homogeneous cosmologies. It is found that such symmetries only occur in the Brans--Dicke theory when the dilaton field self--interacts. Moreover, the interaction potential of the dilaton must take the form of a cosmological constant. For the spatially flat, isotropic model, it is shown how this point symmetry may be employed to generate a discrete scale factor duality in the Brans--Dicke action.

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James E. Lidsey. 1996-03-27. Symmetric vacuum scalar--tensor cosmology. https://doi.org/10.1088/0264-9381%2F13%2F9%2F010

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