On the APM power spectrum and the CMB anisotropy: evidence for a phase transition during inflation?

Abstract

A B S T R A C TAdams et al. have noted that according to our current understanding of the unification of fundamental interactions, there should have been phase transitions associated with spontaneous symmetry breaking during the inflationary era. This may have resulted in the breaking of scale-invariance of the primordial density perturbation for brief periods. A possible such feature was identified in the power spectrum of galaxy clustering in the automated plate measurement (APM) survey at the scale k , 0:1 h Mpc 2 1 and it was shown that the secondary acoustic peaks in the power spectrum of the cosmic microwave background (CMB) anisotropy should consequently be suppressed. We demonstrate that this prediction is confirmed by the recent Boomerang and Maxima observations, which favour a step-like spectral feature in the range k , ð0:06-0:6Þ h Mpc 2 1 , independently of the similar previous indication from the APM data. Such a spectral break enables an excellent fit to both APM and CMB data with a baryon density consistent with the big bang nucleosynthesis (BBN) value. It also allows the possibility of a matter-dominated universe with zero cosmological constant, which we show can now account for even the evolution of the abundance of rich clusters.

Punctuated inflation and the low CMB multipoles

“…[10,38,39,40,41,42,43,44,45]). The degree of the deviation from a nearly scale invariant spectrum would be determined by the extent and duration of the departure, which are, in turn, controlled by the parameters of the model.…”

Evidence for an inflationary phase transition from the LSS and CMB anisotropy data

“…If established this would provide the first direct connection between astronomical data and physics at very high energies. (The reader is referred to [1] for further details, references and acknowledgements).…”

“…Note that the Γ = 0.5 reconstruction has significantly less power than a scale-free H-Z spectrum on scales k > ∼ 0.1hMpc −1 , while the Γ = 0.2 reconstruction is closer to a H-Z spectrum but has relatively more power. Thus the latter possibility does not give a good fit to the Boomerang/MAXIMA data with the value (given above) of the baryon density from big bang nucleosynthesis (the reader is referred to [1] for further comments on this). …”

“…Reconstructing the primordial spectrum 2.1. Primordial spectrum from the APM There are several arguments (reviewed in the Appendix of [1]) that on scales 0.01h −1 Mpc < ∼ k < ∼ 0.6hMpc −1 , which are at most weakly non-linear, the APM galaxy power spectrum P APM (k) [4] is an unbiased (or moderately linearly biased) tracer of the mass. The linear power spectrum recovered under this assumption from P APM (k) is well fitted in this range by [5]:…”

“…From the expressions above we estimate P 0 (k) to be : 3 and A 1 and A 2 are such that make P 0 (k) continuous. For the cosmological parameters which define Γ we consider the observationally indicated values h ∼ 0.5 − 0.8 and Ω B = (0.019 +0.0013 −0.0012 )h −2 [8] (for further discussion see [1])). Figure 1 shows the recovered primordial spectrum (1) for two choices of Γ corresponding to the sCDM model (Γ = 0.5) and a low density variant.…”