Cosmological disformal invariance
نویسندگان
چکیده
منابع مشابه
Disformal invariance of cosmological perturbations in a generalized class of Horndeski theories
It is known that Horndeski theories can be transformed to a sub-class of GleyzesLanglois-Piazza-Vernizzi (GLPV) theories under the disformal transformation of the metric gμν → Ω(φ)gμν +Γ(φ,X)∇μφ∇νφ, where Ω is a function of a scalar field φ and Γ is another function depending on both φ and X = g∇μφ∇νφ. We show that, with the choice of unitary gauge, both curvature and tensor perturbations on th...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2015
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2015/10/067