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Register a new userInhomogeneities in the Microwave Background Radiation interpreted within the framework of the Quasi-Steady State Cosmology
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We calculate the expected angular power spectrum of the temperature fluctuations in the microwave background radiation (MBR) generated in the quasi-steady state cosmology (QSSC). The paper begins with a brief description of how the background is produced and thermalized in the QSSC. We then discuss within the framework of a simple model, the likely sources of fluctuations in the background due to astrophysical and cosmological causes. Power spectrum peaks at $l approx 6-10$, 180-220 and 600-900 are shown to be related in this cosmology respectively to curvature effects at the last minimum of the scale factor, clusters and groups of galaxies. The effect of clusters is shown to be related to their distribution in space as indicated by a toy model of structure formation in the QSSC. We derive and parameterize the angular power spectrum using six parameters related to the sources of temperature fluctuations at three characteristic scales. We are able to obtain a satisfactory fit to the observational band power estimates of MBR temperature fluctuation spectrum. Moreover, the values of `best fit parameters are consistent with the range of expected values.
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In this paper we show that, within the framework of the QSSC, the small scale deviations on angular scales $lesssim 1^{0}$ expected in the MBR are due to inhomogeneities in the distribution of galaxies and clusters. It is shown how these can be estimated on the galaxy-cluster-supercluster scale at the epoch of redshift $sim 5$ when the universe was last passing through the minimum phase of the scale factor. Rich clusters on the scale of 5-10 Mpc generate the kind of peak in the fluctuation power spectrum observed by the Boomrang and Maxima projects. Weaker inhomogeneities on smaller scales with $l~sim 10^3$ are expected to arise from individual galaxies and small groups.
A recently proposed mechanism for large-scale structure in string cosmology --based on massless axionic seeds-- is further analyzed and extended to the acoustic-peak region. Existence, structure, and normalization of the peaks turn out to depend crucially on the overall evolution of extra dimensions during the pre-big bang phase: conversely, precise cosmic microwave background anisotropy data in the acoustic-peak region will provide, within the next decade, a window on string-theorys extra dimensions before their eventual compactification.
A brief historical account of modern cosmology shows that the standard big bang (BB) model, believed by so many, does not have the strong observational foundations that are frequently claimed for it. The theory of the Quasi-Steady State Cosmology (QSSC) and explosive cosmogony is outlined. Comparisons are made between the two theories in explaining the observed properties of the universe, namely, the expansion, chemical composition, CMB, QSO redshifts and explosive events, galaxy formation, and the m-z and theta-z relations. Only two of the observed properties have ever been predicted from the theories (a) the expansion predicted from Einsteins theory by Friedmann and Lemaitre, and (b) the acceleration predicted by the classical steady state theory and the QSSC.
We study inhomogeneities in the distribution of the excursion sets in the Cosmic Microwave Background (CMB) temperature maps obtained by the three years survey of the Wilkinson Microwave Anisotropy Probe (WMAP). At temperature thresholds |T|<90 mu K, the distributions of the excursion sets with over 200 pixels are concentrated in two regions, nearly at the antipodes, with galactic coordinates l= 94^circ.7, b= 34^circ.4 and l= 279^circ.8, b= -29^circ.2. The centers of these two regions drift towards the equator when the temperature threshold is increased. The centers are located close to one of the vectors of ell =3 multipole. The two patterns of the substructures in the distribution of the excursion sets are mirrored, with chi^2=0.7-1.5. There is no obvious origin of this effect in the noise structure of WMAP, and there is no evidence for a dependence on the galactic cut. Would this effect be cosmological, it could be an indication of an anomalously large component of horizon-size density perturbations, independent of one of the spatial coordinates, and/or of a non-trivial slab-like spatial topology of the Universe.
The detection of primordial gravitational waves is one of the biggest challenges of the present time. The existing (Wilkinson Microwave Anisotropy Probe) observations are helpful on the road to this goal, and the forthcoming experiments (Planck) are likely to complete this mission. We show that the 5-year Wilkinson Microwave Anisotropy Probe $TE$ data contains a hint of the presence of gravitational wave contribution. In terms of the parameter $R$, which gives the ratio of contributions from gravitational waves and density perturbations to the temperature quadrupole, the best-fit model produced $R=0.24$. Because of large residual noises, the uncertainty of this determination is still large, and it easily includes the R=0 hypothesis. However, the uncertainty will be strongly reduced in the forthcoming observations which are more sensitive. We numerically simulated the Planck data and concluded that the relic gravitational waves with $R=0.24$ will be present at a better than 3$sigma$ level in the $TE$ observational channel, and at a better than 2$sigma$ level in the `realistic $BB$ channel. The balloon-borne and ground-based observations may provide a healthy competition to Planck in some parts of the lower-$ell$ spectrum.
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