One project is to use Dirac's constraint algorithm to obtain the canonical Hamiltonian formulation of the Poincar'e gauge theories. This will reveal all the constraints and any hidden gauge transformations. For certain values of the parameters we suspect that these theories will also suffer from the constraint bifurcation phenomena which we recently discovered in the teleparallel theory. We are also investigating this curious phenomena as a general problem in applying Dirac's algorithm.

While interesting in its own right, the Hamiltonian formulation is just the first step in another project: to develop and apply the fundamental theoretical requirement of positive total energy as an effective test of alternate theories of gravity. Positive total energy simply means that gravity is universally attractive. We can reject any theory which permits a repulsive solution: ``antigravity''. Hence we try to find such ``bad'' solutions in a proposed alternate theory. Many otherwise viable theories are failing this test.

Our new rotational gauge conditions recently led to a new proof of positive energy for Einstein gravity. We are developing these ideas further. The new gauge conditions select new variables for gravity which may provide a better physical description of the theory and afford a good localization of gravitational energy.