Testing a curvature model using fisher forecasts for a EUCLID-like spectroscopic survey

International audienceCurrent data have shown that the ΛCDM framework gives a good description of theuniverse with a small set of parameters. Although we are able to give very goodconstraints over the cosmological parameters, some physical quantities such asthe curvature isn't directly measured. Even if the general relativity (GR) is akey part of the standard model of the cosmology it has not been already testedon cosmological scales. We propose in this work an extended Newtonianformulation to test the GR relevance through the equivalence between mattercontent and geometry of the Universe, using Fisher forecasts for a Euclid-likeSpectroscopic survey. We found in agreement with previous studies that relaxingthe dark energy equation of state leads to less stringent constraints over boththe curvature and the dark energy