Comparing the effects of curved space and noninertial frames on spin 1/2 particles - art. no. 024016

The most accurate description possible of the behavior of a spin 1/2 partic le in Earth's gravitational field is obtained by writing the Dirac equation in Kerr spacetime. Approximate methods, such as the use of rotating frames in Schwarzschild spacetime and accelerated and rotating frames in Minkowsk i spacetime, can also be used and will in general give different results. I n this paper the orders of magnitude of energies are determined at which th e Hamiltonian in the above cases become distinct, thus enabling one to choo se the appropriate spacetime for the interpretation of experimental results .