The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles

Details The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles

2009-12-15

arxiv.org/abs/0912.2994v2

Phys.Rev.D81:063520,2010

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

31 pages, 10 figures. Version to appear in PRD

Scientific paper

10.1103/PhysRevD.81.063520

We study the entire coupled evolution of the inflaton and the scale factor for general initial conditions at a given initial time. The generic early universe evolution has three stages: decelerated fast-roll followed by inflationary fast roll and then inflationary slow-roll. This evolution is valid for all regular inflaton potentials. In addition, we find a special (extreme) slow-roll solution starting at t = -infty in which the fast-roll stages are absent. At some time t = t_*, the generic evolution backwards in time reaches a mathematical singu- larity where a(t) vanishes and Hubble becomes singular. We find the general behaviour near the singularity. The classical inflaton description is valid for t-t_* > 10 t_{Planck} well before the beginning of inflation, quantum loop effects are negligible there. The singularity is never reached in the validity region of the classical treatment and therefore it is not a real physical phenomenon here. The whole evolution of the fluctuations is computed. The Bunch-Davies initial conditions (BDic) are generalized for the present case. The power spectrum gets dynamically modified by the effect of the fast-roll eras and the BDic choice at a finite time through the transfer function D(k) of initial conditions. D(0) = 0. D(k) presents a first peak for k ~ 2/eta_0 (eta_0 being the conformal initial time), then oscillates with decreasing amplitude and vanishes asymptotically for k -> infty. The transfer function D(k) affects the low CMB multipoles C_l: the change Delta C_l/C_l for l=1-5 is computed as a function of the starting instant of the fluctuations t_0. CMB quadrupole observations give large suppressions which are well reproduced here(Abridged)

Affiliated with

Also associated with

No associations

Rating

The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The pre-inflationary and inflationary fast-roll eras and their signatures in the low CMB multipoles will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-48083