Focusing on Dark Energy with Weak Gravitational Lensing

This thesis is devoted to the study of phaenomenology within the quest for Dark Energy (DE) nature. Nowadays, thanks to the accuracy with which cosmological parameters have been constrained, Cosmology has really turned into a high precision science. In spite of their accuracy, however, data are still far from really constraining DE nature, so that this keeps perhaps the main puzzle in today’s cosmology. Constraints on DE, until now, came from measurements of the Cosmic Microwave Background (CMB), from the Hubble diagram of SupernovæIa, from deep galaxy samples and from a few other observables, as Lyα clouds, galaxy cluster distribution, etc. Such measures will be certainly extended and improved in the next decade(s) leading to more stringent constraints. Even more effective are however expected to be future weak lensing (WL) data, namely in combination with the above classical observables, marking a real turning point to Cosmology. This thesis wants to add a brick to the construction of this wide building, trying to study the impact of tomographic WL measurements on constraining dynamical and/or coupled DE models. Within this context, it will be outlined how massive neutrinos, added to the total cosmological energy balance, allow the consistency with present data of a higher DM–DE coupling. This last issue outlines how tomographic WL observables will allow to shed new light over a problem as neutrino masses, so enriching the patterns through which large scale data influence microphysical issues.