of the system is not algebraically reducible to the DSX dynamical quantities.

Conclusion
==========

The algebraic form of the global relativistic conservation laws has been examined within the perspective of the DSX post-Newtonian dynamics of an $N$-body system. We succeeded in breaking up seven of these conservation laws (mass-energy, center-of-mass quantity, and linear momentum) into a sum of individual contributions involving only the basic dynamical quantities of the DSX formalism. The angular momentum conservation law resisted, however, our efforts.

D. V. finished this work while staying at the OCA/CERGA, Grasse (France) and being supported by an H. Poincaré fellowship. He is also grateful to IHES, Bures sur Yvette (France) for its kind hospitality and partial support.

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