  Einstein thought that he could solve the difficulties of an unstable  non-static universe with boundary conditions at infinity that do not  satisfy Mach’s Principle, by introducing the cosmological term  \(\Lambda\) into his field equations. He showed that for positive values of the cosmological constant, his modified field equation admitted a  solution for a   static[78]  universe in which space is curved, unbounded and finite; that is,  space is a hyper surface of a sphere in four dimensions. Einstein’s spatially closed universe is often  referred to as Einstein’s “cylinder” world: with two of  the spatial dimensions suppressed, the model universe can be pictured as a cylinder where the radius \(A\) represents the space and the  axis the time coordinate. 