K-Chameleon and the Coincidence Problem
| dc.creator | Wei, Hao | |
| dc.creator | Cai, Rong-Gen | |
| dc.date | 2004-12-06 | |
| dc.date | 2005-02-09 | |
| dc.date.accessioned | 2026-07-07T10:50:28Z | |
| dc.date.available | 2026-07-07T10:50:28Z | |
| dc.description | 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 {\bf K} attractor and the other is a completely {\em new}, dubbed {\bf C} attractor. Once the universe is attracted into the {\bf C} attractor, the fraction energy densities of the k-chameleon $Ω_ϕ$ and dust matter $Ω_m$ are fixed and comparable, and the universe will undergo a power-law accelerated expansion. One can adjust the model so that the {\bf K} attractor do not appear. Thus, the k-chameleon model provides a natural solution to the cosmological coincidence problem. | |
| dc.description | Revtex, 17 pages; v2: 18 pages, two figures, more comments and references added, to appear in PRD, v3: published version | |
| dc.identifier | https://arxiv.org/abs/hep-th/0412045 | |
| dc.identifier | http://arxiv.org/abs/hep-th/0412045 | |
| dc.identifier | Phys.Rev.D71:043504,2005 | |
| dc.identifier | doi:10.1103/PhysRevD.71.043504 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/184544 | |
| dc.subject | High Energy Physics - Theory | |
| dc.subject | Astrophysics | |
| dc.subject | General Relativity and Quantum Cosmology | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | K-Chameleon and the Coincidence Problem | |
| dc.type | text |