Principle of the existence of space and the de Sitter metric

The principle proposed in a number of studies [1-6] for selecting solutions of Einstein's equations leads to the existence of space ($g_{ik}\ne0$) only in the presence of matter ($T_{ik}\ne0$). This selection principle (in the terminology of Markov, the principle for the existence of space) leads in general, to the absence of a cosmological solution with de Sitter metric. On the other hand, the de Sitter metric is needed to describe both the inflationary and the deflationary period of the universe. It is shown in the paper that the de Sitter metric too is admissible in the framework of the selection principle if it evolves into the Friedmann metric.