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Mathisson-Papapetrou equations in metric and gauge theories of gravity in a Lagrangian formulation

M. Leclerc
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Abstract

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.

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M. Leclerc. 2005-07-23. Mathisson-Papapetrou equations in metric and gauge theories of gravity in a Lagrangian formulation. https://doi.org/10.1088/0264-9381%2F22%2F16%2F006

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