  An investigation of the spatial fluctuations and their manifestations in the
vicinity of the quantum critical point within the framework of the renormalized
$\phi^{4}$ theory is proposed. Relevant features are reported through the
Ginzburg-Landau-Wilson (GLW)-based calculations, combined with an efficient non
perturbative technique. Both the dimension and size, but also microscopic
details of the system, leading to critical behavior, and strongly deviating
from the classical mean-field approach far from the thermodynamic limit, are
taken into account. Further, the important role that harmonic and anharmonic
fluctuations and finite-size effects can play in the determination of the
characteristic properties of corresponding various systems, involving phase
transitions and critical phenomena, is then discussed in detail with emphasis
on the qualitative validity of the analysis
