Neutrinos and dark energy constraints from future galaxy surveys and CMB lensing information

We explore the possibility of obtaining better constraints from future astronomical data by means of the Fisher information matrix formalism. In particular, we consider how cosmic microwave background (CMB) lensing information can improve our parameter error estimation. We consider a massive neutrino scenario and a time-evolving dark energy equation of state in the Lambda cold dark matter framework. We use Planck satellite experimental specifications together with the future galaxy survey Euclid in our forecast. We found improvements in almost all studied parameters considering Planck alone when CMB lensing information is used. In this case, the improvement with respect to the constraints found without using CMB lensing is of 93\% around the fiducial value for the neutrino parameter. The improvement on one of the dark energy parameters reaches 4.4\%. When Euclid information is included in the analysis, the improvements on the neutrino parameter constraint are of approximately 128\% around its fiducial value. The addition of Euclid information provides smaller errors on the dark energy parameters as well. For Euclid alone, the figure of merit is a factor of similar to 29 higher than that from Planck alone even considering CMB lensing. Finally, the consideration of a nearly perfect CMB experiment showed that CMB lensing cannot be neglected, especially in more precise future CMB experiments, since it provided in our case a six-times-better figure of merit with respect to the unlensed CMB analysis.