  Equivalence principles are a major part of modern relativity theory.
Gravitational shifts can already be calculated within the time domain as motion
shifts, and we examine the consequences of reversing this argument and
describing motion shifts outside the time domain, as effects of curvature
associated with relative velocity. This unusual "Doppler mass shift" approach
appears to resolve some of Einstein's own criticisms of the "SR+GR" model and
seems to remove some barriers to the reconciliation of classical and quantum
theory. The disadvantage of this model is that constant-velocity problems no
longer obey Euclidean geometry. By bypassing special relativity and the special
theory's flat-space assumptions, the model also suggests an alternative
non-transverse frequency-shift relationship. This difference should be
testable.
