Details

Autor(en) / Beteiligte

• Giani, Leonardo
• Piattella, Oliver F.

Titel

Late-times asymptotic equation of state for a class of nonlocal theories of gravity

Ist Teil von

• Physical review. D, 2019-12, Vol.100 (12), p.1, Article 123508

Ort / Verlag

College Park: American Physical Society

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We investigate the behavior of the asymptotic late-times effective equation of state for a class of nonlocal theories of gravity. These theories modify the Einstein-Hilbert Lagrangian introducing terms containing negative powers of the d'Alembert operator acting on the Ricci scalar. We find that imposing vanishing initial conditions for the nonlocal content during the radiation-dominated epoch implies the same asymptotic late-times behavior for most of these models. In terms of the effective equation of state of the Universe, we find that asymptotically ω eff → − 1 , approaching the value given by a cosmological constant. On the other hand, unlike in the case of Λ CDM , the Hubble factor is a monotonic growing function that diverges asymptotically. We argue that this behavior is not a coincidence and discuss under which conditions this is to be expected in these nonlocal models.