  Dipole polarizabilities of light pseudoscalar mesons are calculated in the
framework of the mean field approach to QCD vacuum and bosonization based on
the statistical ensemble of almost everywhere homogeneous Abelian
(anti-)self-dual gluon fields -- the domain model of QCD vacuum. In this
approach, one derives a nonlocal effective action of meson fields which
describes two-point correlation functions and all possible strong, weak and
electromagnetic interactions of meson fields including their excited states.
Specifically, the role of intermediate scalar meson fields in formation of the
polarizabilities is addressed. Within the domain model, the propagators of
scalar meson fields composed of light quark-anti-quark pairs have no poles at
real momenta. It turns out that for charged pions and kaons, the contribution
of intermediate scalar fields to polarizability is substantial, but not the
largest one. The calculated polarizabilities are in reasonable agreement with
COMPASS experimental data and results of Chiral Perturbation Theory.
