 However, if one does this for the model under discussion, understood as an exact solution of the Einstein equations, the resulting picture of matter evolution would not have a general character and would be specific for the high symmetry imminent to the present model.Mathematically, this specificity is related to the fact that for the homogeneous space geometry discussed here, the Ricci tensor components formula_52 are identically zeros and therefore the Einstein equations would not allow movement of matter (which gives non-zero stress energy-momentum tensor components formula_53).In other words, the synchronous frame must also be co-moving with respect to matter.