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Register a new userScalar-tensor cosmologies without screening
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Added by
Leonardo Giuliano Trombetta
Publication date
2020
fields
Physics
and research's language is
English
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Scalar-tensor theories are frequently only consistent with fifth force constraints in the presence of a screening mechanism, namely in order to suppress an otherwise unacceptably large coupling between the scalar and ordinary matter. Here we investigate precisely which subsets of Horndeski theories do not give rise to and/or require such a screening mechanism. We investigate these subsets in detail, deriving their form and discussing how they are restricted upon imposing additional bounds from the speed of gravitational waves, solar system tests and cosmological observables. Finally, we also identify what subsets of scalar-tensor theories precisely recover the predictions of standard (linearised) $Lambdatext{CDM}$ cosmologies in the quasi-static limit.
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