  The paper deals with the scale discrepancy between the observed vacuum energy
in cosmology and the theoretical quantum vacuum energy (cosmological constant
problem). Here, we demonstrate that Einstein's equation and an analogy to
particle physics leads to the first physical justification of the so-called
fine-tuning problem. This fine-tuning could be automatically satisfied with the
variable cosmological term $\Lambda(a)=\Lambda_0+\Lambda_1 a^{-(4-\epsilon)}$,
$0 < \epsilon \ll 1,$ where $a$ is the scale factor.
  As a side effect of our solution of the cosmological constant problem, the
dynamical part of the cosmological term generates an attractive force and
solves the missing mass problem of dark matter.
