Discrete symmetries and general relativity, the dark side of gravity
Résumé
The space-time exchange, parity and time reversal invariant actions, equations and their conjugated metric solutions are obtained in the context of a general relativistic model modified in order to take into account discrete symmetries. The equations are not covariant however the predictions of the model, in particular its Schwarzschild metric solution in vaccuum, only start to differ from those of General Relativity at the Post-Post Newtonian order. No coordinate singularity (Black Hole) arises in the local privileged coordinate system where the energy of gravity is found to vanish. Vaccum energies cancel as gravitational sources in the global privileged coordinate system where a flat universe accelerated expansion phase is obtained without resorting to inflation nor a cosmological constant. The context may be promising to help us elucidate several outstanding enigmas such as the Pioneer anomalous blueshift, flat galactic rotation curves or the universe voids. A gravitational wave solution of a linear equation is obtained with the same binary pulsar decay rate as observed and predicted in GR.