Page "Quasar" Paragraph 17

One great topic of debate during the 1960s was whether quasars were nearby objects or distant objects as implied by their redshift.

It was suggested, for example, that the redshift of quasars was not due to the expansion of space but rather to light escaping a deep gravitational well.

However a star of sufficient mass to form such a well would be unstable and in excess of the Hayashi limit.

Quasars also show ' forbidden ' spectral emission lines which were previously only seen in hot gaseous nebulae of low density, which would be too diffuse to both generate the observed power and fit within a deep gravitational well.

There were also serious concerns regarding the idea of cosmologically distant quasars.

One strong argument against them was that they implied energies that were far in excess of known energy conversion processes, including nuclear fusion.

At this time, there were some suggestions that quasars were made of some hitherto unknown form of stable antimatter and that this might account for their brightness.

Others speculated that quasars were a white hole end of a wormhole.

However, when accretion disc energy-production mechanisms were successfully modeled in the 1970s, the argument that quasars were too luminous became moot and today the cosmological distance of quasars is accepted by almost all researchers.