Proper projective and curvature symmetries in FRW space-times

A study of Friedmann-Robertson-Walker (FRW) space-times according to their symmetries (i.e. proper projective and curvature) is given. Although these results are not new, a different approach is developed to study these symmetries. It is shown that the special class of the above space-times admit proper projective vector fields. The study of the above space-times according to their proper curvature collineations is also given by using the rank of the 6 x 6 Riemann matrix. Studying proper curvature collinations in the above space-times, we show that proper curvature collineations form an infinite-dimensional vector space.