English

A two-scalar model for a small but nonzero cosmological constant

General Relativity and Quantum Cosmology 2009-10-31 v1 Astrophysics

Abstract

We revisit a model of the two-scalar system proposed previously for understanding a small but nonzero cosmological constant. The model provides solutions of the scalar-fields energy ρs\rho_s which behaves truly constant for a limited time interval rather than in the way of tracker- or scaling-type variations. This causes a mini-inflation, as indicated by recent observations. As another novel feature, ρs\rho_s and the ordinary matter density ρm\rho_m fall off always side by side, but interlacing, also like (time)2^{-2} as an overall behavior in conformity with the scenario of a decaying cosmological constant. A mini-inflation occurs whenever ρs\rho_s overtakes ρm\rho_m, which may happen more than once, shedding a new light on the coincidence problem. We present a new example of the solution, and offer an intuitive interpretation of the mechanism of the nonlinear dynamics. We also discuss a chaos-like nature of the solution.

Keywords

Cite

@article{arxiv.gr-qc/9908021,
  title  = {A two-scalar model for a small but nonzero cosmological constant},
  author = {Yasunori Fujii},
  journal= {arXiv preprint arXiv:gr-qc/9908021},
  year   = {2009}
}

Comments

9 pages plus 7 figures

R2 v1 2026-07-22T12:57:09.761Z