We present the transition of the universe from the early decelerating phase to the current accelerating phase with viscous fluid and time-dependent cosmological constant (A) as a source of matter in Bianchi- V spaceti...We present the transition of the universe from the early decelerating phase to the current accelerating phase with viscous fluid and time-dependent cosmological constant (A) as a source of matter in Bianchi- V spacetime.To study the transit behaviour of the universe,we assume the scale factor as an increasing function of time,which generates a time-dependent deceleration parameter (DP).The study revesls that the cosmological term does not change its fundamental nature for ε =const and ε =ε(t),where ε is the coefficient of bulk viscosity.The A(t)is found to be positive and is a decreasing function of time.The same behavior was observed during recent supernovae observations.The physical behaviour of the universe is discussed in detail.展开更多
文摘We present the transition of the universe from the early decelerating phase to the current accelerating phase with viscous fluid and time-dependent cosmological constant (A) as a source of matter in Bianchi- V spacetime.To study the transit behaviour of the universe,we assume the scale factor as an increasing function of time,which generates a time-dependent deceleration parameter (DP).The study revesls that the cosmological term does not change its fundamental nature for ε =const and ε =ε(t),where ε is the coefficient of bulk viscosity.The A(t)is found to be positive and is a decreasing function of time.The same behavior was observed during recent supernovae observations.The physical behaviour of the universe is discussed in detail.
