2004/12/31 by Hao Wei, Rong-Gen Cai · 2 citations
Mathematics · Physics and Astronomy · #Astrophysics #Attractor #Coincidence #Cosmology and Gravitation Theories #Coupling (piping) #Dark Matter and Cosmic Phenomena #Field (mathematics) #Galaxies: Formation, Evolution, Phenomena #Mathematical analysis #Mathematical physics #Mathematics #Omega #Physics #Pure mathematics #Quantum mechanics #Theoretical physics #Universe #astro-ph #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.71.043504
published as Phys.Rev.D71:043504,2005 · Revtex, 17 pages; v2: 18 pages, two figures, more comments and references added, to appear in PRD, v3: published version
openalex publication_date 2005/02/08 · arxiv created 2005/02/09 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In this paper we present a hybrid model of k-essence and chameleon, named as k-chameleon. In this model, due to the chameleon mechanism, the directly strong coupling between the k-chameleon field and matters (cold dark matters and baryons) is allowed. In the radiation-dominated epoch, the interaction between the k-chameleon field and background matters can be neglected; the behavior of the k-chameleon therefore is the same as that of the ordinary k-essence. After the onset of matter domination, the strong coupling between the k-chameleon and matters dramatically changes the result of the ordinary k-essence. We find that during the matter-dominated epoch, only two kinds of attractors may exist: one is the familiar K attractor and the other is a completely new, dubbed C attractor. Once the Universe is attracted into the C attractor, the fraction energy densities of the k-chameleon \ensuremathΩ_\ensuremathφ and dust matter \ensuremathΩm are fixed and comparable, and the Universe will undergo a power-law accelerated expansion. One can adjust the model so that the K attractor does not appear. Thus, the k-chameleon model provides a natural solution to the cosmological coincidence problem.