Foundations of Physics

, Volume 48, Issue 10, pp 1364–1379 | Cite as

Unimodular quantum gravity and the cosmological constant

  • R. PercacciEmail author
Part of the following topical collections:
  1. Black holes, Gravitational waves and Space Time Singularities


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.


Cosmological constant Quantum gravity Unimodular 



This paper is based in part on joint work with R. de León Ardón and N. Ohta. I also thank M. Henneaux and S. Gielen for discussions and D. Benedetti and A. Eichhorn for reading parts of the manuscript and making useful suggestions.


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Authors and Affiliations

  1. 1.SISSATriesteItaly
  2. 2.INFN, Sezione di TriesteTriesteItaly

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