Unimodular quantum gravity and the cosmological constant

@article{Percacci2018UnimodularQG,
  title={Unimodular quantum gravity and the cosmological constant},
  author={Roberto Percacci},
  journal={Foundations of Physics},
  year={2018},
  volume={48},
  pages={1364-1379}
}
  • R. Percacci
  • Published 28 December 2017
  • Physics
  • Foundations of Physics
It is shown that the one-loop effective action of unimodular gravity is the same as that of ordinary gravity, restricted to unimodular metrics. The only difference is in the treatment of the global scale degree of freedom and of the cosmological term. A constant vacuum energy does not gravitate, addressing one aspect of the cosmological constant problem. 

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