Onset of the nonlinear regime in unified dark matter models

• Type: Article in International Scientific Journal
• Date: 2004

Authors

Avelino, PP (Author) FCUP; Beca, LMG (Author) Other; de Carvalho, JPM (Author) FCUP; Martins, CJAP (Author) Other; Copeland, EJ (Author) Other

Journal

Title: Physical Review D: Particles and fields

Vol. 69

ISSN: 0556-2821

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 43 Citations

Scopus - 47 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-000-BVZ

DOI: 10.1103/physrevd.69.041301

Abstract (EN): We discuss the onset of the nonlinear regime in the context of unified dark matter models involving a generalized Chaplygin gas. We show that the transition from dark-matter-like to dark-energy-like behavior will never be smooth. In some regions of space the transition will never take place while in others it may happen sooner or later than naively expected. As a result the linear theory used in previous studies may break down late in the matter dominated era even on large cosmological scales. We study the importance of this effect showing that its magnitude depends on the exact form of the equation of state in the low density regime. We expect that our results will be relevant for other unified dark matter scenarios, particularly those where the quartessence candidate is a perfect fluid.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5