Scalar field mass in generalized gravity
نویسنده
چکیده
The notions of mass and range of a Brans-Dicke-like scalar field in scalar-tensor and f(R) gravity are subject to an ambiguity that hides a potential trap. We spell out this ambiguity and identify a physically meaningful and practical definition for these quantities. This is relevant when giving a mass to this scalar in order to circumvent experimental limits on the PPN parameters coming from Solar System experiments. PACS numbers: 04.20.-q, 04.50.+h
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