In the case of Komar mass, we can express the mass as an integral of ##\rho + 3P##, so we can meaningful divide the total mass (or energy) of a system into the contribution due to each part, just by integrating over that spatial part of the system.(adsbygoogle = window.adsbygoogle || []).push({});

What happens if we try to do this with other definitions of mass, say the ADM or Bondi mass? My overall impression is that it can't be done, but I don't have a specific reference for this, so I want to be cautious about saying it cant be done.

I suppose I'm open to general ways of partitioning the mass, and not just my suggested approach of integrating some (pseudo) tensor of some sort over a spatial region.

One obstacle that comes to mind with psuedotensors is the obvious issue of the gauge degree of freedom affecting the subdivision process. But this seems lacking as a proof of impossibility, at least without an example illustrating different "partitioning".

**Physics Forums - The Fusion of Science and Community**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Assigning energy (and maybe mometum) to part of a system in GR.

Loading...

Similar Threads - Assigning energy maybe | Date |
---|---|

A Dark Matter and the Energy-Momentum Tensor | Mar 12, 2018 |

I A question about the relativistic energy dispersion relation | Feb 20, 2018 |

I Stress–energy pseudotensor of gravitation field for DE | Jan 30, 2018 |

I Mass-Energy derivation | Jan 28, 2018 |

Assignment of Variables Help! | Jun 10, 2010 |

**Physics Forums - The Fusion of Science and Community**