Viscosity in modified gravity

Abstract

A bulk viscosity is introduced in the formalism of modified gravity. It is shown that, on the basis of a natural scaling law for the viscosity, a simple solution can be found for quantities such as the Hubble parameter and the energy density. These solutions may incorporate a viscosity-induced Big Rip singularity. By introducing a phase transition in the cosmic fluid, the future singularity can nevertheless in principle be avoided.

9 pages, no figure; reference list updated and expanded

References in corpus (17)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Introduction to Modified Gravity and Gravitational Alternative for Dark Energy
• Dark energy cosmology: the equivalent description via different theoretical models and cosmography tests
• Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
• Can dark energy evolve to the Phantom?
• Covariant conservation of energy momentum in modified gravities
• Consistent modified gravity: dark energy, acceleration and the absence of cosmic doomsday
• Dark Energy and Viscous Cosmology
• Viscous Little Rip Cosmology
• Non-singular exponential gravity: a simple theory for early- and late-time accelerated expansion
• Entropy and universality of Cardy-Verlinde formula in dark energy universe
• Modified equation of state, scalar field, and bulk viscosity in Friedmann universe
• Viscous FRW Cosmology in Modified Gravity
• Turbulence and Little Rip Cosmology
• Crossing of the w=-1 barrier in viscous modified gravity
• Crossing of the w=-1 Barrier in Two-Fluid Viscous Modified Gravity
• Viscous Modified Gravity on a RS Brane Embedded in AdS5

Cited by in corpus (13)

• Bulk viscous matter and the cosmic acceleration of the universe in $f(Q,T)$ gravity
• Constraining $f(Q,L_m)$ gravity with bulk viscosity
• Observational constraints on the equation of state of viscous fluid in $f(R,T)$ gravity
• Constraining viscous dark energy equation of state in $f(R,L_m)$ gravity
• Viscous cosmology in $f(T)$ gravity
• Effective equation of state in modified gravity and observational constraints
• Phase-space analysis of the viscous fluid cosmological models in the coincident $f(Q)$ gravity
• Cosmic acceleration with bulk viscosity in an anisotropic $f(R,L_m)$ background
• Bulk viscous cosmological model in $f(T,\mathcal{T})$ modified gravity
• Viscous fluid cosmology in symmetric teleparallel gravity
• Bulk viscous fluid in symmetric teleparallel cosmology: theory versus experiment
• Observational constraints on viscous cosmology in $f(T,L_m)$ gravity
• Cosmological constraints in symmetric teleparallel gravity with bulk viscosity