Research Papers (JVN)
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Item Doppler theory of quasars(Indian Academy of Sciences, 1981-04-28) Narlikar, J. V.; Edmunds, M. G.We examine a Doppler theory of quasars in which it is assumed that a fraction of the total population of quasars are fired from centres of explosion with moderate cosmological redshifts. It is argued that the substantial part of the redshift of a typical high redshift quasar could be of Doppler origin. If Hoyle’s recent hypothesis that quasars emit the bulk of their radiation in a narrow backward cone is given a quantitative form, it is shown that the kinematic and emission parameters of this model can explain the observed features of the four aligned triplets of quasars discovered by Arp and Hazard (1980) and by Saslaw (personal communication). The model predicts a small but nonzero fraction of quasars with blueshifts. Further observational tests of the model are discussed.Item Dust model for the cosmic microwave background(Kluwer Academic Publishers, 1975-02-07) Narlikar, J. V.; Edmunds, M. G.; Wickramasinghe, N. C.; et al.The cosmic microwave background may be explained on the basis of absorption and reemission of the light from galaxies by graphite whiskers of lengths l⋍0.1-1 mm. The mass density of such particles required is of the order of 10−³⁴ g cm−³ .Item Limits on a microwave background without the big bang(Pergamon, 1976-01-11) Narlikar, J. V.; Edmunds, M. G.; Wickramasinghe, N. C.The possibility of explaining the cosmic microwave back- ground in terms of thermalisation of radiation from such sources as galaxies by dust grains is explored further. Relevant calcula- tions of the optical cross-sections of graphite whiskers are given and it is shown that a smeared out dust density of ^ 10~³³ g cm~³ is required. Limits are set on the large-angle anisotropy of the background which is to be expected on the basis of this model. The relative merits of the conventional explanation and the present theory are discussed and a few discriminatory observational tests proposed. Some cosmological implications of whisker grains in the intergalactic space are examined.