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Indexed by:Journal Papers

Date of Publication:2019-09-01

Journal:JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

Included Journals:SCIE

Issue:9

ISSN No.:1475-7516

Key Words:modified gravity; cosmology of theories beyond the SM; gravity; inflation

Abstract:A self-consistent model which can unify Starobinsky inflation and the Lambda CDM model in the framework of Poincare gauge cosmology (PGC) is studied in this work, without extra inflaton and "dark energy". We start from the general nine-parameter PGC Lagrangian and get two Friedmann-like analytical solutions with the certain ghost-and tachyon-free conditions on the Lagrangian parameters. The scalar torsion h-determined solution is consistent with Starobinsky cosmology in the early-time and the pseudo-scalar torsion f-determined solution contains naturally a constant "dark energy" density, 3(alpha - 1)(2)/8B(0), which covers the Lambda CDM model in the late-time. According to the latest observations, we estimate the magnitudes of parameters: alpha - 1 similar or equal to 8.07 x 10(-56), B-0 similar or equal to 5.76 x 10(-28) GeV-2 in the natural units.