On the solutions of the Cartan equation in Metric Affine Gravity
  In the Tucker-Wang approach to Metric Affine gravity we review some particular solutions of the Cartan equation for the non-riemannian part of the connection. As application we show how a quite general non Riemannian model gives a Proca type equation for the trace of the nonmetricity 1-forms Q. 
Roberto Mignani (University of Rome III) Roberto Scipioni (University   of British Columbia)