Static Solutions for 4th order gravity
  The Lichnerowicz and Israel theorems are extended to higher order theories of
gravity. In particular it is shown that Schwarzschild is the unique spherically
symmetric, static, asymptotically flat, black-hole solution, provided the
spatial curvature is less than the quantum gravity scale outside the horizon.
It is then shown that in the presence of matter (satisfying certain positivity
requirements), the only static and asymptotically flat solutions of General
Relativity that are also solutions of higher order gravity are the vacuum
solutions
