Tetrad Fields and Gravitational Fields

The consequences of the hypothesis that gravitation may be described by a tetrad field, are examined by studying the most general Lagrargian obtained as a linear combination of invariants. A particular choice of these can be made on the basis of correspondence with the Newtonian theory. The field equations obtained from this particular Lagrangian, although somewhat different from those of Moller, give rise, in the case of a static, spherically symmetric system, to the usual Schwarzschild metric. Moreover, in the cases considered explicitly by Moller, the solutions of the field equations are the same. A conserved energymomentum complex having the property that the energy density is localizable is also derived. The use of a tetrad field to describe the structure of space- time allows the introduction of spinor fields, and in particular of the neutrino field, in a natural way. A new coupling between fermions and gravitation also follows from this theory. (auth)