Inflation with R <sub>(αβ)</sub> terms in the Palatini formulation
نویسندگان
چکیده
We study inflation with the most general non-degenerate gravitational action that depends on symmetric part of Ricci tensor coupled to a scalar field in Palatini formulation gravity. use redefinitions shift effect terms from gravity field, and apply result slow-roll inflation. As examples, we consider actions quadratic cubic tensor. In case results are similar $R+\alpha R^2$ has been studied earlier: tensor-to-scalar ratio $r$ can be suppressed by an arbitrary amount, while spectrum is unaffected. case, at factor $2/9$, change spectral index $n_s$ large.
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2021
ISSN: ['1475-7516', '1475-7508']
DOI: https://doi.org/10.1088/1475-7516/2021/09/032