Einstein introduced lambda parameter L determining his world model - the so-called Einstein-cosmos (Einstein 1917). I evaluate its variability how following with those interpretation, which Stephani gave:

+L means properties of gravitation of ordinary mass (coino-masse).

-L gives the qualities of antimass.

The coupled inside of one equation describing our world's properties, the positive L should give a positive curvature of cosmos. In special case, the cosmos is locked or closed. The presence of negative mass would lead to the contrary effect with negative L: the cosmos would be induced to get a negative curvature, first by weakening of positive curvature down to zero and deeper. If both L-parameters were compensated to zero, the space would be flat then. Although it should not have some curvature any more, the solution makes a constant curvature (this seems to be our vacuum like a stationary spherical body). In this space neither mass nor antimass are existing free. Or both are existing as vacuum quanta in the same distribution. Vacuum quanta cannot induce special curvature. Because the complete stationary space of collecting vacuum quanta is a sphere, there a curved world limit exists - the so-called constant curvature. Each circular orbit is part of a flat space in this vacuum space. The more of such circular orbits are given by real bodies, the more the real flat space becomes a three-dimensional relationship, in which time only is the equivalent for these three way-coordinates x, y and z while it determines them with t_x, t_y and t_z. The real fourth coordinate is j²=-1, which determines mathematically, that two different cosms are separated from each other, because their three-dimensional coordinate system is only valid inside of their isolated cosms.

(cf.: Stephani, Allgemeine Relativitätstheorie, pp 243 and 244, Berlin 1980, VEB Deutscher Verlag der Wissenschaften)

Present interpreters mean, lambda parameter could be smaller with a larger part of negative value. Then there would be a factor opening the space. This way they try to explain why galaxies appear in larger and larger distances and why the local density decreases, the more far we optically go away from the "start" of universe. Really there is a magnitude with accelerating action in universe! This should be L now by free manipulating manually. In opposite, I explain you what magnitude has really had its accelerating action making an increasing inflation.