Cosmology in time asymmetric extensions of general relativity

Abstract

We investigate the cosmological behavior in a universe governed by time asymmetric extensions of general relativity, which is a novel modified gravity based on the addition of new, time-asymmetric, terms on the Hamiltonian framework, in a way that the algebra of constraints and local physics remain unchanged. Nevertheless, at cosmological scales these new terms can have significant effects that can alter the universe evolution, both at early and late times, and the freedom in the choice of the involved modification function makes the scenario able to produce a huge class of cosmological behaviors. For basic ansatzes of modification, we perform a detailed dynamical analysis, extracting the stable late-time solutions. Amongst others, we find that the universe can result in dark-energy dominated, accelerating solutions, even in the absence of an explicit cosmological constant, in which the dark energy can be quintessence-like, phantom-like, or behave as an effective cosmological constant. Moreover, it can result to matter-domination, or to a Big Rip, or experience the sequence from matter to dark energy domination. Additionally, in the case of closed curvature, the universe may experience a cosmological bounce or turnaround, or even cyclic behavior. Finally, these scenarios can easily satisfy the observational and phenomenological requirements. Hence, time asymmetric cosmology can be a good candidate for the description of the universe.

42 pages, 6 figures, 8 tables, version published in JCAP

References in corpus (20)

• Dynamics of dark energy
• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Resummation of Massive Gravity
• Dark torsion as the cosmic speed-up
• Einstein's Other Gravity and the Acceleration of the Universe
• Covariant Galileon
• Modified f(R) gravity consistent with realistic cosmology: from matter dominated epoch to dark energy universe
• Membranes at Quantum Criticality
• Generalized Galileons: All scalar models whose curved background extensions maintain second-order field equations and stress tensors
• Cosmological perturbations in f(T) gravity
• Horava-Lifshitz Cosmology
• Construction of cosmologically viable f(G) gravity models
• Teleparallel equivalent of Gauss-Bonnet gravity and its modifications
• Dynamical behavior in $f(T,T_G)$ cosmology
• Einstein gravity as a 3D conformally invariant theory
• Cosmological applications of $F(T,T_G)$ gravity
• Dynamical analysis of generalized Galileon cosmology
• Fourth order Weyl gravity
• Dynamics of a scalar field in Robertson-Walker spacetimes
• Time asymmetric extensions of general relativity

Cited by in corpus (8)

• Dynamical systems applied to cosmology: dark energy and modified gravity
• Falsifying cosmological models based on a non-linear electrodynamics
• Generalized Tachyonic Teleparallel cosmology
• Generalized scalar field cosmologies: theorems on asymptotic behavior
• Time-averaging axion-like interacting scalar fields models
• Generalized Scalar Field Cosmologies: A Global Dynamical Systems Formulation
• Averaging Generalized Scalar Field Cosmologies I: Locally Rotationally Symmetric Bianchi III and open Friedmann-Lemaître-Robertson-Walker models
• Cosmological signatures of time-asymmetric gravity