KALUZA-KLEIN TYPE COSMOLOGICAL MODEL WITH Omega-DEPENDENT COSMOLOGICAL CONSTANT AND BIG RIP SINGULARITY

In this paper by using the modified EOS of the formp= rho-f(rho) we investigate the evolution of the scale factor in Kaluza-Klein type cosmological model in which cosmological constant is given by the scalar arisen by the contraction of the scale energy tensor. It is shown that the big rip singularity occurs at finite time t = t(s), by violating null, weak, strong energy condition and satisfying the dominant energy condition for alpha > 0. For the general case f(rho) = alpha rho((beta+1/2)), it is observed that for beta= 1/2 >0,R(t) rho(t) andH(t) ->infinity are reached at a finite time s = 2/b(0), whereb 0 is constant. So again take place big rip singularity at a finite time. However, for beta < 0, singularity does not occurs at a finite time in the framework of Kaluza-Klein theory of gravitation.