if $g_{p}(u,v)=g(u,v)$ for $u, v\in T_{p}M$,

For any $u, v\in T_{p}M $ we have $g_p (u, v)=(g_p)_{ij}\cdot u^i v^j,$ where $ u^i, v^j$ are coordinates of vectors $u, v$ in the basis $\{ \partial_i \}$ and $(g_p)_{ij}=g_p(\partial_i ,\partial_j)$. We have that $det\|(g_p)_{ij}\|\# 0 $ and matrix $\|(g_p)_{ij}\|$ is invertible.

By using the fact that tangent spaces are $R$-modules we define the tensor bundles under formal manifold.

In [@KoR] was developed the original theory of connections in a context of SDG. There it was shown that connections on the bundles over a subobject $U$ of $R^n$ were defined by $3n$ coefficients $\Gamma_{ij}^k$ and that the tensor of curvature (tensor of Riemann-Christoffel) had the classical expression in coordinates.

So we define the connection on formal manifold by means of definition of $\Gamma_{ij}^k$ in a local chart and than introduce the tensor of curvature by using the its coordinates $R_{ijk}^l$ in a local chart which are expressed in a classical manner. It is evident that in this case the Riemann-Christoffel’s tensor has a standart properties. Further we can define the Ricci’s and Einstein’s tensors by using the classical operations over tensors.

Now we can write the Einstein’s equations of gravitational field if we 