If I understand right, GR says that internal motions in an object add to its gravitational mass, because there is associated kinetic energy. My question is, do all observers agree on the quantity of gravitational mass?(adsbygoogle = window.adsbygoogle || []).push({});

To an observer far away from the object, the object's internal motions would appear slower due to gravitational time dilation, so wouldn't the distant observer assign the object a lower internal kinetic energy than another observer deep in its gravity well? If so, do the two observers each measure a different gravitational mass, or does some other effect cancel out the apparent difference in kinetic energy?

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# Do all observers agree on gravitational mass?

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