  Compton wavelength and Schwarzschild radius are considered here as limiting
cases of a unified length scale. Using this length, it is shown that the Dirac
equation and the Einstein equations for a point mass are limiting cases of an
underlying theory which includes torsion. We show that in this underlying
theory the gravitational interaction between small masses is weaker than in
Newtonian gravity. We explain as to why the Kerr-Newman black hole and the
electron both have the same non-classical gyromagnetic ratio. We propose a
duality between curvature and torsion and show that general relativity and
teleparallel gravity are respectively the large mass and small mass limit of
the ECSK theory. We demonstrate that small scale effects of torsion can be
tested with current technology.
