Talk detail

Participant	Starobinsky, Alexei
Institution	Landau Institute for Theoretical Physics RAS - 2, Kosygina - Moscow - Moscow - Russia

Session	DE1	Accepted		Order	Time
Talk	Oral abstract	Title	Reconstruction of primordial dark energy in f(R) gravity
Coauthors
Abstract	Results of the old paper by Hodges and Blumenthal (1990) on the reconstruction of an inflaton potential for inflation driven by a scalar field in GR, given a primordial spectrum of scalar perturbations generated during it, are generalized to the case of inflation driven by primordial dark energy in f(R) gravity which occurs when f(R)=R^2A(R) for some range of values of the Ricci scalar R where A(R) is a slowly changing function (so gravity becomes approximately scale-free in this regime). The simplest forms of A(R) producing the best fit to the measured slope of the primordial scalar spectrum n_s are discussed and resulting predictions for the tensor-to-scalar ratio r are presented. Among these models, the R+R^2 model leading to n_s = 1 - 2/N and r = 12/N^2 is distinguished by the aesthetic assumptions of the absence of additional scales (parameters) during and after inflation and smooth transition to the GR regime at small R.
Pdf file