General relativity. What does momentum conservation mean?

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Discussion Overview

The discussion revolves around the concept of momentum conservation in the context of general relativity (GR). Participants explore whether "momentum conservation" refers to the conservation of 4-momentum or 3-momentum, and the implications of this distinction within GR.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant questions whether momentum conservation in GR refers to 4-momentum or 3-momentum.
  • Another participant states that conservation of 4-momentum encompasses the conservation of 3-momentum, energy, and mass.
  • A different participant seeks clarification on the specific definition of "momentum conservation" within the context of GR.
  • One participant suggests that there is no universal rule and that each author should define their terms clearly.

Areas of Agreement / Disagreement

Participants express differing views on the definition of momentum conservation in GR, indicating that multiple competing interpretations exist without a consensus.

Contextual Notes

Participants note the importance of definitions and clarity in discussing momentum conservation, highlighting the potential for varied interpretations among different authors.

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In general relativity, does momentum conservation mean conservation of 4-momentum or 3-momentum
 
Last edited:
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Conservation of 4 momentum includes the conservation of 3 momentum, the conservation of energy, and the conservation of mass
 
I know that. But I am asking the definition of the phrase "Momentum conservation" in the context of GR. Does it mean 4- or 3-momentum conservation?
 
I don't think there is a general rule. Each author should clarify their meaning
 

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