  Quantum Electrodynamics (QED) has been so successful a theory that it is
taken as a model for the production of further quantum theories. However, when
the prescription for quantising electromagnetic interactions that so
successfully resulted in QED is applied to General Relativity the theory
obtained is not renormalizable. We derive a different method of quantising
classical electromagnetism which also results in QED. We call the method the
versatile method. We then apply the versatile method to General Relativity, in
particular the Einstein equation which equates a geometrical description
derivable from the metric to the energy-momentum-stress tensor, or as we shall
call it the matter tensor of the matter field. The method can be applied
provided that there is always a reference frame, which may differ with location
and time, where the matter tensor can be reduced to a mass density with the
other elements zero. We call such matter tensors simple. This restriction means
that the tensor can be put into one to one correspondence with the Dirac
current. When the versatile method of quantising a classical theory is applied
to General Relativity the theory that results is renormalizable. It is in fact
isomorphic to QED, provided that the temporal and a spatial co-ordinate are
exchanged.

General Relativity and Quantum Cosmology