@MISC{Souradeep92cosmicmicrowave, author = {Tarun Souradeep and Varun Sahni}, title = {Cosmic Microwave Background by}, year = {1992} }

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Abstract

We asses the contribution to the observed large scale anisotropy of the cosmic microwave background radiation, arising from both gravity waves as well as adiabatic density perturbations, generated by a common inflationary mechanism in the early Universe. We find that for inflationary models predicting power law primordial spectra |δk | 2 ∝ k n, the relative contribution to the quadrupole anisotropy from gravity waves and scalar density perturbations, depends crucially upon n. For n < 0.87, gravity waves perturb the CMBR by a larger amount than density perturbations, whereas for n> 0.87 the reverse is true. Normalising the amplitude of the density perturbation spectrum at large scales, using the observed value of the COBE quadrupole, we determine (δM/M)16 – the rms density contrast on scales ∼ 16h −1 50 Mpc, for cosmological models with cold dark matter. We find that for n < 0.75, a large amount of biasing is required in order to reconcile theory with observations.