Spinor Theory of Gravity
  The proposal of this work is to provide an answer to the following question: is it possible to treat the metric of space-time - that in General Relativity (GR) describes the gravitational interaction - as an effective geometry? In other words, to obtain the dynamics of the metric tensor as a consequence of the dynamics of other fields. In this work we will use a slight modfication of the non-linear equation of motion of a spinor field proposed some years ago by Heisenberg, although in a completely distinct context, to obtain a field theory that provides a framework equivalent to the way GR represents the gravitational interaction. In particular we exhibit a solution of the equations of motion that represents the gravitational field of a compact object and compare it with the corresponding Schwarzschild solution of General Relativity. 
M. Novello