Stationary analogs of de Sitter and anti-de Sitter spacetimes: Evidence in favor of $\mathrm{\Lambda }$ as a dark fluid

We introduce novel Einstein spaces which are the {\it stationary analogs of de Sitter and ani-de Sitter} spacetimes. Having $\mathrm{\Lambda }$ as their only parameter, the inherent anisotropy in these solutions appears as a dilemma if we treat the cosmological term as a constant background curvature. Since the cosmological term is an inseparable element of the current cosmological models, further development of these models as well as resolution of the problems related to this term, including any quantum aspect will crucially depend on the true nature of this term. These solutions, which to the best of our knowledge appear here for the first time in the literature, not only open a new direction to study the cosmological term, but also provide strong evidence in favor of the cosmological term as a dark fluid, hence furnishing a resolution to the above mentioned dilemma.