Soft coincidence in late acceleration

Abstract

We study the coincidence problem of late cosmic acceleration by assuming that the present ratio between dark matter and dark energy is a slowly varying function of the scale factor. As dark energy component we consider two different candidates, first a quintessence scalar field, and then a tachyon field. In either cases analytical solutions for the scale factor, the field and the potential are derived. Both models show a good fit to the recent magnitude-redshift supernovae data. However, the likelihood contours disfavor the tachyon field model as it seems to prefer a excessively high value for the matter component.

27 pages, 10 eps figures, to be published in Physical Review D

References in corpus (6)

• Simulating the joint evolution of quasars, galaxies and their large-scale distribution
• WMAP constraints on low redshift evolution of dark energy
• Observational constraints on interacting quintessence models
• 511 KeV Photons From Color Superconducting Dark Matter
• Late Universe expansion dominated by domain walls and dissipative dark matter
• What We Already Know About Quintessence

Cited by in corpus (25)

• Cosmological Evolution With Interaction Between Dark Energy And Dark Matter
• Effects of the interaction between dark energy and dark matter on cosmological parameters
• Interacting Dark Energy and Dark Matter: observational Constraints from Cosmological Parameters
• Testing the viability of the interacting holographic dark energy model by using combined observational constraints
• Stability of the curvature perturbation in dark sectors' mutual interacting models
• Signature of the interaction between dark energy and dark matter in galaxy clusters
• Cosmological coincidence problem in interacting dark energy models
• Observational constraints on the dark energy and dark matter mutual coupling
• Interacting models of soft coincidence
• Signature of the interaction between dark energy and dark matter in observations
• Dynamics of Interacting Quintessence Models: Observational Constraints
• Constraining non-minimally coupled tachyon fields by Noether symmetry
• A preliminary analysis of the energy transfer between the dark sectors of the Universe
• Models of vacuum energy interacting with cold dark matter: Constraints and comparison
• Dark-Energy Dynamics Required to Solve the Cosmic Coincidence
• The mass and the coupling of the Dark Particle
• Cosmological Condensation of Scalar Fields -- Making a dark energy
• An interacting holographic dark energy model within an induced gravity brane
• Field independent cosmic evolution
• Anisotropic Dark Energy and the Generalized Second Law of Thermodynamics
• Reconstruction of the interaction term between dark matter and dark energy using SNe Ia
• Cosmic acceleration in screening hybrid quintessence model
• Reconstruction of the interaction term between dark matter and dark energy using SNe Ia, BAO, CMB, H(z) and X-ray gas mass fraction
• Some Classes of Interacting Two-Fluid Model of the Expanding Universe
• Stability Analysis of DGP Brane-world Model with Agegraphic Dark Energy