Weyl scaling invariant R2 gravity for inflation and dark matter

Inflation in the early universe can generate the nearly conformal invariant fluctuation that leads to the structures we observe at the present. The simple viable Starobinsky R2 inflation has an approximate global scale symmetry. We study the conformal symmetric Weyl Rˆ2 and general F(Rˆ) theories an...

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Bibliographic Details
Main Authors: Yong Tang, Yue-Liang Wu
Format: Article
Language:English
Published: Elsevier 2020-10-01
Series:Physics Letters B
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269320305190
Description
Summary:Inflation in the early universe can generate the nearly conformal invariant fluctuation that leads to the structures we observe at the present. The simple viable Starobinsky R2 inflation has an approximate global scale symmetry. We study the conformal symmetric Weyl Rˆ2 and general F(Rˆ) theories and demonstrate their equivalence to Einstein gravity coupled with a scalar and a Weyl gauge field. The scalar field in Weyl Rˆ2 gravity can be responsible for inflation with Starobinsky model as the attractor, potentially distinguishable from the latter by future experiments. The intrinsic Weyl gauge boson becomes massive once the Einstein frame is fixed, and constitutes as a dark matter candidate with mass up to ∼5×1016GeV.
ISSN:0370-2693