I Quasi-local mass as a measure of the gravitational energy?

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Quasi-local mass, or quasi-local energy, is a concept in general relativity that measures gravitational energy, raising questions about its interpretation since gravity is not viewed as a force but as a curvature of spacetime. The discussion highlights the need for specific references to ground the inquiry in established research, with a suggestion to consult an arXiv paper for further insights. The term "quasi-local mass" is noted to be more familiar among experts in mathematical relativity. The core question remains focused on understanding how quasi-local mass can quantify gravitational energy without treating gravity as a force field. This inquiry into the nature of gravitational energy continues to prompt deeper exploration in the field.
Steve Rogers
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How can we talk about the gravitational energy without considering it as a force field?
I'm self-studying the mathematical aspects of quasi-local mass, or quasi-local energy (e.g. Hawking energy), and a fundamental question has been lingering in my mind for a long time: why does quasi-local mass provide us with a measure of the gravitational energy? In general relativity, gravitation is seen as a consequence of the curved spacetime instead of a force in classical mechanics. If so, how can we talk about its energy without considering it as a force field? Thank you.
 
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Steve Rogers said:
quasi-local mass, or quasi-local energy
Please give a specific reference for where you are getting this from. Without a specific reference we do not have a valid basis for discussion.
 
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PeterDonis said:
Please give a specific reference for where you are getting this from. Without a specific reference we do not have a valid basis for discussion.
Hello, a quick reference for this topic can be found on arXiv, as follows.
https://arxiv.org/abs/1510.02931

I guess the term "quasi-local mass" is more familiar to people working on mathematical relativity or mathematical physics, such as Shing-Tung Yau and Robert Geroch.

Thank you for replying.
 
Steve Rogers said:
a quick reference for this topic can be found on arXiv, as follows.
Thanks for the reference. Can you point out which particular part of it is the basis for your question?

Steve Rogers said:
why does quasi-local mass provide us with a measure of the gravitational energy?
 
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