1999/08/06 by Yasunori Fujii
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #astro-ph #gr-qc
paper · pdf · doi:10.1103/physrevd.62.064004
published as Phys.Rev. D62 (2000) 064004 · 9 pages plus 7 figures
arxiv created 1999/08/06 · openalex publication_date 2000/07/31 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We reexamine a model of the two-scalar system proposed previously for understanding a small but nonzero cosmological constant. The model provides solutions of the scalar-field energy \ensuremathρs which behaves as a true constant for a limited time interval rather than in the way of tracker- or scaling-type variations. This causes mini-inflation, as indicated by recent observations. As another novel feature, \ensuremathρs and the ordinary matter density \ensuremathρm always fall off side by side, but interlacing, also as (time)^\ensuremath-2 as an overall behavior in conformity with the scenario of a decaying cosmological constant. Mini-inflation occurs whenever \ensuremathρs overtakes \ensuremathρm, which may happen more than once, shedding 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 the chaoslike nature of the solution.