  Spontaneous Lorentz symmetry breaking can occur when the dynamics of a tensor
field cause it to take on a non-zero expectation value in vacuo, thereby
providing one or more "preferred directions" in spacetime. Couplings between
such fields and spacetime curvature will then affect the dynamics of the
metric, leading to interesting gravitational effects. Bailey & Kostelecky
developed a post-Newtonian formalism that, under certain conditions concerning
the field's couplings and stress-energy, allows for the analysis of
gravitational effects in the presence of Lorentz symmetry breaking. We perform
a systematic survey of vector models of spontaneous Lorentz symmetry breaking.
We find that a two-parameter class of vector models, those with kinetic terms
we call "pseudo-Maxwell," can be successfully analyzed under the
Bailey-Kostelecky formalism, and that one of these two "dimensions" in
parameter space has not yet been explored as a possible mechanism of
spontaneous Lorentz symmetry breaking.
