Abstract :
A dynamical model of the decaying vacuum energy is presented, which is based on Jordan-Brans-Dicke theory with a scalar field φ. The solution of an evolutionary differential equation for the scalar field φ drives the vacuum energy towards a cosmological constant at the present epoch that can give for the age of the universe, t0 ∼ 13.5 Gyr for Ω0 = 1, which is consistent with the age of globular clusters.
