General Relativity
The stress-energy tensor is a second-order tensor field containing energy-momentum densities, energy-momentum fluxes, and shear stresses, of a mass-energy distribution. The divergence of this tensor vanishes:
because energy and momentum are conserved. This is an important constraint on the form the Einstein field equations take in general relativity.
Read more about this topic: Continuity Equation
Famous quotes containing the words general and/or relativity:
“A poet’s object is not to tell what actually happened but what could or would happen either probably or inevitably.... For this reason poetry is something more scientific and serious than history, because poetry tends to give general truths while history gives particular facts.”
—Aristotle (384–323 B.C.)
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