Critical closed matter-cosmological-constant universe
= Critical closed matter-cosmological-constant universe
For positive spatial curvature and positive <cosmological constant>, the effective potential has its maximum at
$$
a_E=\left(\frac{3\mu}{2\Lambda}\right)^{1/3}.
$$
The critical case $V(a_E)=-1$ has
$$
\Lambda=\frac{4}{9\mu^2},
\qquad
a_E=\frac{3\mu}{2}=\Lambda^{-1/2},
$$
and contains the <Einstein static universe>.