  We quantize the interaction of gravity with Yang-Mills and spinor fields,
hence offering a quantum theory incorporating all four fundamental forces of
nature. Let us\ann{as} abbreviate the spatial Hamilton functions of the
Standard Model by $H_{SM}$ and the Hamilton function of gravity by $H_G$.
Working in a fiber bundle $E$ with base space $\socc=\R[n]$, where the fiber
elements are Riemannian metrics, we can express the Hamilton functions in the
form $H_G+H_{SM}=H_G+t^{-\frac23}\tilde H_{SM}$ if $n=3$, where $\tilde H_{SM}$
depends on metrics $\s_{ij}$ satisfying $\det{\s_{ij}}=1$. In the quantization
process, we quantize $H_G$ for general $\s_{ij}$ but $\tilde H_{SM}$ only for
$\s_{ij}=\de_{ij}$ by the usual methods of QFT. Let $v$ \resp $\psi$ be the
spatial eigendistributions of the respective Hamilton operators, then, the
solutions $u$ of the Wheeler-DeWitt equation are given by $u=wv\psi$, where $w$
satisfies an ODE and $u$ is evaluated at $(t,\de_{ij})$ in the fibers.
