INTRODUCTION

Since their discovery, the nature of quasars has been one of the most intriguing and baffling problems as evinced by the following quotations:

'... the problem of understanding quasi-stellar objects ... is one of the most important and fascinating tasks in all physics' - G.Burbidge and Hoyle,
' The quasar continues to rank both as one of the most baffling objects in the universe and one most capable of inspiring heated argument' - Morrison,
' The redshift problem is one of the most critical problems in astronomy today.' G.Burbidge,
' ...quasars still remain the profoundest mystery in the heavens' Hazard and Mitton.

The conventional interpretation of the spectral lines observed in quasars is based on the redshift hypothesis. Three hypotheses have been advanced to account for the supposed redshifts:

Cosmological hypothesis; the redshifts are due to the expansion of the universe,
Gravitational hypothesis,
Local-Doppler hypothesis; in this hypothesis the redshifts are due to the Doppler effect, but the quasars are relatively nearby and have nothing to do with the expansion of the universe.

Of these hypotheses, the first one is the most publicized one. Terell gives a good account of the difficulties present in the cosmological redshift hypothesis.

One is led to attribute to quasars very many mysterious properties if one assumes the redshift hypothesis to be correct. A patient analysis of the data on quasars over the years led the author to the conclusion that the real source of the trouble is in the assumption that the spectra of quasars have redshifts. In 1973, the author proposed a radically different explanation of the spectra of quasars. In this paper we give the salient features of this theory and compare it to the cosmological redshift hypothesis. For the sake of clarity we shall confine ourselves to quasars in this paper.

Next Section: The new theory.