Phantom Dark Energy, Cosmic Doomsday, and the Coincidence Problem

Abstract

Phantom dark energy models, with w < -1, are characterized by a future singularity and therefore a finite lifetime for the universe. Because the future singularity is triggered by the onset of dark-energy domination, the universe spends a significant fraction of its total lifetime in a state for which the dark energy and matter densities are roughly comparable. We calculate, as a function of w, the fraction of the total lifetime of the universe for which the dark energy and matter densities differ by less than the ratio r_0 in either direction. For r_0 = 10, this fraction varies from 1/3 to 1/8 as w varies from -1.5 to -1.1; the fraction is smaller for smaller values of r_0. This result indicates that the coincidence problem is significantly ameliorated in phantom-dominated cosmologies with a future singularity.

4 pages, 1 figure, more references and discussion added, to appear in Phys. Rev. D

References in corpus (4)

• The final state and thermodynamics of dark energy universe
• Quantum effects can render w<-1 on cosmological scales
• Quantum escape of sudden future singularity
• The Fate of Bound Systems in Phantom and Quintessence Cosmologies

Cited by in corpus (58)

• Gauss-Bonnet dark energy
• Holographic dark energy and cosmic coincidence
• Dark Energy: Vacuum Fluctuations, the Effective Phantom Phase, and Holography
• The Little Rip
• Interacting dark energy, holographic principle and coincidence problem
• Hubble expansion & Structure Formation in Time Varying Vacuum Models
• Two Loop Scalar Self-Mass during Inflation
• "Expansion" around the vacuum equation of state - sudden future singularities and asymptotic behavior
• Cosmological Evolution of Interacting Phantom Energy with Dark Matter
• Quantum Stability of a w < - 1 Phase of Cosmic Acceleration
• Charged Black Holes in Phantom Cosmology
• LXCDM: a cosmon model solution to the cosmological coincidence problem?
• Observational constraints on the dark energy and dark matter mutual coupling
• Some Issues Concerning Holographic Dark Energy
• Statefinder parameters for quintom dark energy model
• Finite-time Cosmological Singularities and the Possible Fate of the Universe
• A Note on Crossing the Phantom Divide in Hybrid Dark Energy Model
• Comparison of Approaches to Quantum Correction of Black Hole Thermodynamics
• Dark energy perturbations and cosmic coincidence
• Dark energy transition between quintessence and phantom regimes - an equation of state analysis
• Phantom Dark Energy Models with a Nearly Flat Potential
• Phantom Dark Energy Models with Negative Kinetic Term
• Large-scale inhomogeneities in modified Chaplygin gas cosmologies
• Constraints on a variable dark energy model with recent observations
• Testing power-law cosmology with galaxy clusters
• Rip cosmological models in extended symmetric teleparallel gravity
• Interacting viscous dark fluids
• Composite dark energy: cosmon models with running cosmological term and gravitational coupling
• Mass varying neutrinos, symmetry breaking, and cosmic acceleration
• Dark-Energy Dynamics Required to Solve the Cosmic Coincidence
• Anthropic versus cosmological solutions to the coincidence problem
• Archimedean-type force in a cosmic dark fluid: III. Big Rip, Little Rip and Cyclic solutions
• Can universe exit from phantom inflation due to gravitational back reaction?
• Dynamical System Analysis for a phantom model
• A study of phantom scalar field cosmology using Lie and Noether symmetries
• Reconstructing the properties of dark energy from recent observations
• Cosmic acceleration and de Sitter expansion in hybrid mass varying neutrino model
• A stringy perspective on the coincidence problem
• Higher dimensional cosmological model with a phantom field
• Qualitative analysis and characterization of two cosmologies including scalar fields
• The Coincidence Problem and the Swampland Conjectures in the Ijjas-Steinhardt Cyclic Model of the Universe
• Dynamical systems analysis of an interacting scalar field model in an anisotropic universe
• Dark Energy and Dark Matter Interaction: Kernels of Volterra Type and Coincidence Problem
• Vacuum energy sequestering and cosmic dynamics
• Sudden Future Singularities in Quintessence and Scalar-Tensor Quintessence Models
• The coincidence problem in $f(R)$ gravity models
• Coincidence Problem in Cyclic Phantom Models of the Universe
• Asymptotically Static Universe
• Cosmological scalar fields that mimic the $\Lambda CDM$ cosmological model
• Early dark energy and scalarization in a scalar-tensor model
• Quantum Bias Cosmology: Acceleration from Holographic Information Capacity
• The nature of cosmological singularities in isotropic universes and braneworlds
• Stability Analysis of DGP Brane-world Model with Agegraphic Dark Energy
• Onset of dark energy from cosmological scalarization and gravitational wave speed
• Self-interaction in a cosmic dark fluid: The four-kernel rheological extension of the equations of state
• Sudden Future Singularities and their observational signatures in Modified Gravity
• Apocalypse When? Solar System Constraints on an Imminent Big Rip
• Singularities and Soft-Big Bang in a viscous $\Lambda$CDM model