Pontential energies and potential-energy tensors for subsystems: general properties

R. Caimmi

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arXiv · 1611.06697

Pontential energies and potential-energy tensors for subsystems: general properties

R. Caimmi

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Abstract

With regard to generic two-component systems, the theory of first variations of global quantities is reviewed and explicit expressions are inferred for subsystem potential energies and potential-energy tensors. Performing a conceptual experiment, a physical interpretation of subsystem potential energies and potential-energy tensors is discussed. Subsystem tidal radii are defined by requiring an unbound component in absence of the other one. To this respect, a few guidance examples are presented as: (i) an embedding and an embedded homogeneous sphere; (ii) an embedding and an embedded truncated, singular isothermal sphere where related centres are sufficiently distant; (iii) a homogeneous sphere and a Roche system i.e. a mass point surrounded by a vanishing atmosphere. The results are discussed and compared with the findings of earlier investigations.

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R. Caimmi. 2016-11-21. Pontential energies and potential-energy tensors for subsystems: general properties. https://arxiv.org/abs/1611.06697

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