Radio Sources opposite Quasars as a Cosmological Test

Abstract

IN a previous communication1 I discussed the possibility of having a closed universe model with the pole at a red-shift z ≃ 1.7. One possible observation in such a universe would be images in opposite or near opposite directions to the original object, if the object is not too far from the pole. I showed that this may happen for a few radio sources listed in the 4C radio catalogues2. Another possible observation is to look for radio sources opposite known quasars. To illustrate such an investigation I will refer to a cosmological model with a pole at red-shift 1.7, deceleration parameter q0 = −1.4 and a density parameter σ0 = 0.085. In this model objects must have lifetimes of the order of 1–10 × 109 yr to be seen in two directions, because of the difference in light travel time. This lifetime is too long for a quasar, but it may be possible to observe the object in a pre-quasar or post-quasar stage as a radio source or even as a faint optical object.