Interacting realization of cosmological singularities with variable vacuum energy

Abstract

We examine an interacting dark matter--variable vacuum energy model for a spatially flat Friedmann-Roberston-Walker spacetime, focusing on the appearance of cosmological singularities such as \emph{big rip, big brake, big freeze}, and \emph{ big separation} along with abrupt events (\emph{infinite $\gamma$- singularity} and \emph{new w-singularity}) at late times. We introduce a phenomenological interaction which has a nonlinear dependence on the total energy density of the dark sector and its derivative, solve exactly the source equation for the model and find the energy density as function of the scale factor as well as the time dependence of the approximate scale factor in the neighborhood of the singularities. We describe the main characteristics of these singularities by exploring the type of interaction that makes them possible along with behavior of dark components near them. We apply the geometric Tipler and Królak method for determining the fate of time-like geodesic curves around the singularities. We also explore the strength of them by analyzing the leading term in some geometric invariants such as the square Riemann scalar and the Ricci scalar.

10 pages, 1 figure. All comments are welcome

References in corpus (17)

• Future of the universe in modified gravitational theories: Approaching to the finite-time future singularity
• The future evolution and finite-time singularities in $F(R)$-gravity unifying the inflation and cosmic acceleration
• Worse than a big rip?
• Classification of cosmological milestones
• Barotropic index w-singularities in cosmology
• On the generalised Chaplygin gas: worse than a big rip or quieter than a sudden singularity?
• Singular Inflation
• Strings at future singularities
• A quantitative analysis of singular inflation with scalar-tensor and modified gravity
• Quantum cosmology and late-time singularities
• $w$-cosmological singularities
• Interacting Cosmological Fluids and the Coincidence Problem
• Dark radiation and dark matter coupled to holographic Ricci dark energy
• Interacting dark sector with variable vacuum energy
• Geodesics at Sudden Singularities
• Dark matter, dark energy, and dark radiation coupled with a transversal interaction
• Grand Rip and Grand Bang/Crunch cosmological singularities

Cited by in corpus (9)

• Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution
• Phantom singularities and their quantum fate: general relativity and beyond
• Recent advances in cosmological singularities
• On sign-changeable interaction in FLRW cosmology
• Finite time future singularities in the interacting dark sector
• Type V singularities in non-standard cosmological backgrounds
• Type V singularities with inhomogeneous equations of state
• The frozen vanilla model: Exploring dark sector interactions with delta effective theories
• Cosmological sudden singularities in $f(R,T)$ gravity