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Multipole particle in relativity

Akira Ohashi
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Abstract

We discuss the motion of extended objects in a spacetime by considering a gravitational field created by these objects. We define multipole moments of the objects as a classification by Lie group SO(3). Then, we construct an energy-momentum tensor for the objects and derive equations of motion from it. As a result, we reproduce the Papapetrou equations for a spinning particle. Furthermore, we will show that we can obtain more simple equations than the Papapetrou equations by changing the center-of-mass.

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Akira Ohashi. 2003-06-16. Multipole particle in relativity. https://doi.org/10.1103/physrevd.68.044009

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