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NationMaster - Encyclopedia: Einstein's field equation (Site not responding. Last check: ) |
 | | In physics, the Einstein field equation or Einstein equation is a differential equation in Einstein's theory of general relativity. |
 | | Electromagnetism is the physics of the electromagnetic field: a field, encompassing all of space, which exerts a force on those particles that possess a property known as electric charge, and is in turn affected by the presence and motion of such particles. |
 | | In general relativity, Einsteins field equations can be derived from an action principle starting from the Einstein-Hilbert action: where g is the (pseudo)Riemannian metric, R is the Ricci scalar, n is the number of spacetime dimensions and k is a constant which depends on the units chosen... |
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