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Multipolar Expansions for the Relativistic N-Body Problem in the Rest-Frame Instant Form

D. Alba·L. Lusanna·M. Pauri
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Abstract

Dixon's multipoles for a system of N relativistic positive-energy scalar particles are evaluated in the rest-frame instant form of dynamics. The Wigner hyperplanes (intrinsic rest frame of the isolated system) turn out to be the natural framework for describing multipole kinematics. In particular, concepts like the {\it barycentric tensor of inertia} can be defined in special relativity only by means of the quadrupole moments of the isolated system.

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D. Alba, L. Lusanna, M. Pauri. 2001-03-13. Multipolar Expansions for the Relativistic N-Body Problem in the Rest-Frame Instant Form. https://doi.org/10.1063/1.1897841

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