Averaging inhomogeneities in scalar-tensor cosmology
نویسندگان
چکیده
The backreaction of inhomogeneities on the cosmic dynamics is studied in the context of scalar-tensor gravity. Due to terms of indefinite sign in the non-canonical effective energy tensor of the Brans–Dicke-like scalar field, extra contributions to the cosmic acceleration can arise. Brans–Dicke and metric f(R) gravity are presented as specific examples. Certain representation problems of the formalism peculiar to these theories are pointed out. PACS numbers: 98.80.-k, 98.80.H, 04.20.-q, 04.90.+e
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