Published for SISSA by Springer Received: March 10, 2019 Revised: May 29, 2020 Accepted: July 7, 2020 Published: August 4, 2020 Four-dimensional gravity on a covariant noncommutative space JHEP08(2020)001 G. Manolakos,a P. Manousselisa and G. Zoupanosa;b;c;d aPhysics Department, National Technical University, Zografou Campus 9, Iroon Polytechniou str, GR-15780 Athens, Greece bInstitute of Theoretical Physics, D-69120 Heidelberg, Germany cMax-Planck Institut f¨urPhysik, Fohringer Ring 6, D-80805 Munich, Germany dLaboratoire d' Annecy de Physique Theorique, Annecy, France E-mail:
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[email protected] Abstract: We formulate a model of noncommutative four-dimensional gravity on a co- variant fuzzy space based on SO(1,4), that is the fuzzy version of the dS4. The latter requires the employment of a wider symmetry group, the SO(1,5), for reasons of covari- ance. Addressing along the lines of formulating four-dimensional gravity as a gauge theory of the Poincar´egroup, spontaneously broken to the Lorentz, we attempt to construct a four-dimensional gravitational model on the fuzzy de Sitter spacetime. In turn, first we consider the SO(1,4) subgroup of the SO(1,5) algebra, in which we were led to, as we want to gauge the isometry part of the full symmetry. Then, the construction of a gauge theory on such a noncommutative space directs us to use an extension of the gauge group, the SO(1,5)×U(1), and fix its representation. Moreover, a 2-form dynamic gauge field is included in the theory for reasons of covariance of the transformation of the field strength tensor.