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Register a new userThe innocuousness of adiabatic instabilities in coupled scalar field-dark matter models
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Added by
Pier Stefano Corasaniti
Publication date
2010
fields
Physics
and research's language is
English
Authors
Pier Stefano Corasaniti
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Non-minimally coupled scalar field models suffer of unstable growing modes at the linear perturbation level. The nature of these instabilities depends on the dynamical state of the scalar field. In particular in systems which admit adiabatic solutions, large scale instabilities are suppressed by the slow-roll dynamics of the field. Here we review these results and present a preliminary likelihood data analysis suggesting that along adiabatic solutions coupled models with coupling of order of gravitational strength can provide viable cosmological scenarios satisfying constraints from SN Ia, CMB and large scale structure data.
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