CONSTRAINTS ON HYBRID METRIC-PALATINI GRAVITY FROM BACKGROUND EVOLUTION
In this work, we introduce two models of the hybrid metric-Palatini theory of gravitation. We explore their background evolution, showing explicitly that one recovers standard General Relativity with an effective cosmological constant at late times. This happens because the Palatini Ricci scalar evolves toward and asymptotically settles at the minimum of its effective potential during cosmological evolution. We then use a combination of cosmic microwave background, supernovae, and baryonic accoustic oscillations background data to constrain the models’ free parameters. For both models, we are able to constrain the maximum deviation from the gravitational constant G one can have at early times to be around 1%.
- OSTI ID:
- 22521530
- Journal Information:
- Astrophysical Journal, Vol. 818, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cosmology of hybrid metric-Palatini f(X)-gravity
f(R) gravity theories in Palatini formalism: Cosmological dynamics and observational constraints