Upper Limit of the Age of the Universe with Cosmological Constant

The Friedmann, Robertson-Walker universe is based on the assumption that the universe is exactly homogeneous and isotropic. This model expresses that there is an all encompassing big bang singularity in the past as the origin from which the universe emerges in a very hot phase and continues its expansion as it cools. Here homogeneous and isotropic assumptions of the observed universe are not strictly followed to calculate the present age of the universe. Einstein equation plays an important role in cosmology to determine the present age of the universe. The determination of present age and density of the universe are two very important issues in cosmology, as they determine the future evolution and the nature of the universe. An attempt has been taken here to find the upper limit of the age of the universe with cosmological constant.