# Positive energy in quantum gravity

@article{Smolin2014PositiveEI, title={Positive energy in quantum gravity}, author={Lee Smolin}, journal={Physical Review D}, year={2014}, volume={90}, pages={044034} }

This paper addresses the question of whether Witten’s proof of positive ADM energy for classical general relativity[3] can be extended to give a proof of positive energy for a non-perturbative quantization of general relativity. To address this question, a set of conditions is shown to be sufficient for showing the positivity of a Hamiltonianoperatorcorrespondingto theADM energy. One oftheseconditions is a particular factor ordering for the constraints of general relativity, in a representation…

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