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}
}
  • L. Smolin
  • Published 10 June 2014
  • Physics
  • Physical Review D
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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