An exact analytic spectrum of relic gravitational waves in an accelerating universe
| dc.creator | Zhang, Yang | |
| dc.creator | Er, XinZhong | |
| dc.creator | Xia, TianYang | |
| dc.creator | Zhao, Wen | |
| dc.creator | Miao, HaiXing | |
| dc.date | 2006-04-21 | |
| dc.date | 2008-11-28 | |
| dc.date.accessioned | 2026-07-07T12:05:01Z | |
| dc.date.available | 2026-07-07T12:05:01Z | |
| dc.description | An exact analytic calculation is presented for the spectrum of relic gravitational waves in the scenario of accelerating Universe $Ω_Λ+Ω_m = 1$. The spectrum formula contains explicitly the parameters of acceleration, inflation, reheating, and the (tensor/scalar) ratio, so that it can be employed for a variety of cosmological models. We find that the spectrum depends on the behavior of the present accelerating expansion. The amplitude of gravitational waves for the model $Ω_Λ=0.65$ is about $\sim 50 %$ greater than that of the model $Ω_Λ=0.7$, an effect accessible to the designed sensitivities of LIGO and LISA. The spectrum sensitively depends on the inflationary models with $a(τ) \propto |τ|^{1+β}$, and a larger $β$ yields a flatter spectrum, producing more power. The current LIGO results rule out the inflationary models of $β\geq -1.8$. The LIGO with its design sensitivity and the LISA will also be able to test the model of $β=-1.9$. We also examine the constraints on the spectral energy density of relic gravitational waves. Both the LIGO bound and the nucleosynthesis bound point out that the model $β=-1.8$ is ruled out, but the model $β=-2.0$ is still alive. The exact analytic results also confirm the approximate spectrum and the numerical one in our previous work. | |
| dc.description | 27 pages, 14figures, minor typos corrected | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0604456 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0604456 | |
| dc.identifier | Class.Quant.Grav.23:3783-3800,2006 | |
| dc.identifier | doi:10.1088/0264-9381/23/11/007 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/208274 | |
| dc.subject | Astrophysics | |
| dc.title | An exact analytic spectrum of relic gravitational waves in an accelerating universe | |
| dc.type | text |