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September 6

Stress-energy tensor

Why is it called "stress energy tensor", although its components intended to refer to the energy - actually refer to the energy divided by the speed of light squared - i.e. actually refer to the (relativistic) mass? HOTmag (talk) 13:14, 6 September 2024 (UTC)[reply]

Check out the Stress-energy tensor#Components section where the components of the tensor are normal or shear stress, momentum or energy. The energy is the sum of energy and mass. Graeme Bartlett (talk) 21:55, 6 September 2024 (UTC)[reply]

It seems that your last sentence contains some logical mistake. That's why I couldn't figure out your answer.

Anyway, don't you agree, that whenever any component of this tensor refers to the energy of a given body - this component actually refers to the energy divided by the speed of light squared - i.e. actually refers to the (relativistic) mass? HOTmag (talk) 18:49, 7 September 2024 (UTC)[reply]

Relativistic mass just is energy. The only difference is the units, and not even that if you use units in which the speed of light is 1. So it's a little hard to figure out what your question means. --Trovatore (talk) 18:43, 8 September 2024 (UTC)[reply]