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    Statistical significance of a large quasar inhomogeneity in the sky
    (EDP Sciences, 1985-05-09) Narlikar, J. V.; Subramanian, Kandaswamy
    Statistical techniques are devised to study the significance of apparent inhomogeneities in the distribution of points on a spherical surface, especially in the form of jets and chains. The methods are applied to complete samples of radio quasars in specific windows of magnitudes and redshifts. It is found that while most of the distributions studied show very little evidence of non-randomness, the inhomogeneity reported by Arp (1984) is highly significant. There is also some evidence, although a statistically weaker one, for a chainlike structure in the distribution of low redshift quasars in another area of the sky.
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    Counter images in closed elliptical friedmann universes
    (American Astronomical Society, 1985-01-06) Narlikar, J. V.; Seshadri, T. R.
    It is shown that the different connectivity implied by the elliptical version of a closed Friedmann model allows two images of a distant astronomical object to be seen, provided the deceleration parameter q0 of the Friedmann model exceeds unity. Of the two images the direct image is along the shortest-route light track. If the redshift of the direct image exceeds (1.5q0 - 1)/(q0 - 1)sq then a second counterimage should be visible at the diametrically antipodal position. The direct image has a maximum possible redshift, and it is suggested that the apparent cutoff in the redshifts of QSOs may be due to this effect. Other observable consequences of this result are discussed in relation to galaxies and QSOs.
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    3C 273 : A gravitationally lensed quasar?
    (EDP Sciences, 1984-05-30) Chitre, S. M.; Narasimha, D.; Narlikar, J. V.; et al.
    It is suggested that the abnormal brightness of the quasar 3C 273, coupled with the observations of superluminal motions in its radio core B as well as the misalignment of its VLBI jet with the optical jet, can be understood by postulating a faint spheroidal lensing galaxy located about halfway along the line of sight to the quasar. The lens model also helps to understand why the quasar is found slightly off-centre with respect to its nebulosity. The probability for such a lens system to arise for 3C 273 by chance is shown to be no less than that computed on the basis of the relativistic beaming hypothesis. Further tests of the lens model are discussed.
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    Quasars Q 2345 + 007 A,B and 3C 273 : Gravitational Lenses?
    (Liege University Press, Liege, 1983-01-14) Narlikar, J. V.; Subramanian, Kandaswamy; Narasimha, D.; et al.
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    Observational limitations of the Doppler theory of quasars
    (American Astronomical Society, 1982-09-13) Narlikar, J. V.; Subramanian, Kandaswamy
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    Anomalous redshifts of quasi-stellar objects
    (American Astronomical Society, 1980-09-01) Narlikar, J. V.; Das, P. K.
    This paper is based on the assumption that the observational evidence to date does point to the possibility that high-redshift quasars are physically associated with low-redshift galaxies. It is first argued that the excess (or anomalous) redshifts of the quasars in such associations are unlikely to be either of Doppler or of gravitational origin. A new source for this excess redshift was suggested by Narlikar on the basis of the Hoyle-Narlikar theory of gravitation which is based on Mach's principle. This idea is applied to the hypothesis that quasars may have been ejected from galactic nuclei. The dynamics of such an ejection and its observable consequences are discussed. In particular, it is shown that quasar alignments and redshift bunching which have been observed recently can be understood within the framework of this theory. Further tests of this hypothesis are discussed.
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    Extragalactic universe: an alternative view
    (Nature Publishing Group, 1990-08-30) Narlikar, J. V.; Arp, H. C.; Burbidge, G.; et al.
    We discuss evidence to show that the generally accepted view of the Big Bang model for the origin of the Universe is unsatisfactory. We suggest an alternative model that satisfies the constraints better.
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    Doppler interpretation for close pairs and compact groups of quasars
    (American Astronomical Society, 1989-03-01) Narasimha, D.; Narlikar, J. V.
    We consider a Doppler model to account for (a) abnormal concentration of quasars in a given part of the sky and (b) the presence of two quasars with very nearly equal redshifts lying close to each other. The ejection parameters are explicitly determined and are shown to be reasonable for the nine quasars in the 1146+111 field. This example illustrates both (a) and (b). It is suggested that these calculations be carried out for quasars usually believed to be gravitationally lensed, as well as to other fields containing anomalously high concentration of quasars.