1 research outputs found
Mathisson-Papapetrou equations in metric and gauge theories of gravity in a Lagrangian formulation
We present a simple method to derive the semiclassical equations of motion
for a spinning particle in a gravitational field. We investigate the cases of
classical, rotating particles (pole-dipole particles), as well as particles
with intrinsic spin. We show that, starting with a simple Lagrangian, one can
derive equations for the spin evolution and momentum propagation in the
framework of metric theories of gravity and in theories based on a
Riemann-Cartan geometry (Poincare gauge theory), without explicitly referring
to matter current densities (spin and energy-momentum). Our results agree with
those derived from the multipole expansion of the current densities by the
conventional Papapetrou method and from the WKB analysis for elementary
particles.Comment: 28 page