Einstein Field Equations in Polynomial Form

Einstein Field Equations in Polynomial Form


Einstein's Field equations (and the action from which it is derived) are sometimes, I would say mistakenly, said to be `highly non-polynomial'. This little article explains one method of writing the equations so they are polynomial in a redefinition of the metric tensor to a suitable metric tensor-density. 


Another way to put the equations in polynomial form when there is a diliton field such as in Brans-Dicke gravity is to absorb the determinants of the metric into the definition of the diliton field. 

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