Gravitation of the Casimir Effect and the Cosmological Non-Constant
  Whereas the total energy in zero-point fluctuations of the particle physics vacuum gives rise to the cosmological constant problem, differences in the vacuum give rise to real physical phenomena, such as the Casimir effect. Hence we consider the zero-point energy bound between two parallel conducting plates -- proxy for a solid slice of cosmological constant -- as a convenient laboratory in which to investigate the gravitation and inertia of vacuum energy. We calculate the Casimir effect in a weak gravitational field, obtaining corrections to the vacuum stress-energy and attractive force on the plates due to the curvature of spacetime. These results suggest that if the cosmological constant is due to zero-point energy then it is susceptible to fluctuations induced by gravitational sources. 
R. R. Caldwell (Dartmouth)