Cosmology for Scalar Fields with Negative Potentials and w <-1
| dc.creator | de la Macorra, A. | |
| dc.creator | German, G. | |
| dc.date | 2002-12-05 | |
| dc.date | 2004-02-04 | |
| dc.date.accessioned | 2026-07-07T02:06:44Z | |
| dc.date.available | 2026-07-07T02:06:44Z | |
| dc.description | We study the cosmology of canonically normalized scalar fields that lead to an equation of state parameter of w_ϕ=p_ϕ/ρ_ϕ<-1 without violating the weak energy condition: rho=Σ_iρ_i \geq 0 and ρ_i+p_i\geq 0. This kind of behavior requires a negative scalar potential V, widely predicted in particle physics. We show that the energy density ρ_ϕ=E_k+V takes negative values with an equation of state with w_ϕ< -1. However, the net effect of the $ϕ$ field on the scale factor is to decelerate it giving a total equation of state parameter w=p/ρ> w_b=p_b/ρ_b, where ρ_b stands for any kind of energy density with -1\leq w_b \leq 1. The fact that ρ_ϕ<0 allows, at least in principle, to have a small cosmological constant or quintessence today as the cancellation of high energy scales such as the electroweak or susy breaking scale. While V is negative |ρ_ϕ| is smaller than the sum of all other energy densities regardless of the functional form of the potential V. We show that the existence of a negative potential leads, inevitable, to a collapsing universe, i.e. to a would be "big crunch". In this picture we would still be living in the expanding universe. | |
| dc.description | LaTeX 15 pages, 14 figures. Minor changes. Accepted in IJMPD | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0212148 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0212148 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/5466 | |
| dc.subject | Astrophysics | |
| dc.title | Cosmology for Scalar Fields with Negative Potentials and w <-1 | |
| dc.type | text |