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We give a fully covariant energy momentum stress tensor for the gravitationalfield which is easily physically motivated, and which leads to a very generalderivation of the Einstein equation for gravity. We do not need to assume anyproperty of the surce matter fields' energy momentum stress tensor other thansymmetry. We give a physical motivation for this choice using laser lightpressure. As a consequence of our derivation, the energy momentum stress tensorfor the total source matter and fields must be divergence free, when spacetimeis 4 dimensional. Moreoverr, if the total source matter fields are assumed tobe divergence free, then either spacetime is dimension 4 or the spacetime hasconstant scalar curvature.

The Fully Covariant Energy Momentum Stress Tensor For Gravity and the Einstein Equation in General Relativity