Relation Between the Gravitational and Inertial Masses and Conservation Laws

We assumed before that the electromagnetic field is influenced by the gravitational field. We also can assume that the gravitational field is influenced by the electromagnetic field. We remind that we assume the first approximation of the law of gravitation in the form of ( 4.67 ), i.e. \({\left\{ \begin{array}{ll} {\text {curl}}_{\textbf{x}}\left( {\text {curl}}_{\textbf{x}}\textbf{v}\right) = 0,\\ \frac{\partial }{\partial t}\left( {{\,\textrm{div}\,}}_{\textbf{x}}\textbf{v}\right) +{{\,\textrm{div}\,}}_{\textbf{x}}\left\{ \left( {{\,\textrm{div}\,}}_{\textbf{x}}\textbf{v}\right) \textbf{v}\right\} +\frac{1}{4}\left| d_{\textbf{x}}\textbf{v}+\{d_{\textbf{x}}\textbf{v}\}^T\right| ^2-\left( {{\,\textrm{div}\,}}_{\textbf{x}}\textbf{v}\right) ^2= -4\pi GM, \end{array}\right. }\) where M is the density of gravitational masses. However, till now, we said nothing about the relation between the density of inertial and gravitational masses.