Geometric Perfect Fluids from Extended Gravity

Abstract

A main issue in cosmology and astrophysics is whether the dark sector phenomenology originates from particle physics, then requiring the detection of new fundamental components, or it can be addressed by modifying General Relativity. Extended Theories of Gravity are possible candidates aimed in framing dark energy and dark matter in a comprehensive geometric view. Considering the concept of perfect scalars, we show that the field equations of such theories naturally contain perfect fluid terms. Specific examples are developed for the Friedman-Lemaître-Roberson-Walker metric.

7 pages, accepted for publication in Europhysics Letters

References in corpus (6)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Dark energy cosmology: the equivalent description via different theoretical models and cosmography tests
• Extended Theories of Gravity and their Cosmological and Astrophysical Applications
• Cosmological inflation in $F(R,\mathcal{G})$ gravity
• Tracing the cosmic history by Gauss-Bonnet gravity
• w=1/3 to w=-1 evolution in a Robertson-Walker space-time with constant scalar curvature