Galaxy metallicity, a result of the integrated star formation history and evolution of the interstellar medium, is an important property describing the galaxy evolution. As such it has been widely studied in the local Universe with the data from the SDSS, as well as its relations with galaxy stellar mass and SFR. The relation between these three galaxy physical properties, known as Fundamental Metallicity Relation (FMR), was shown not to undergo any significant evolution at least up to z~2. Despite that, different studies find some differences in 2D projections of this relation.
After the construction of a better framework in which compare different samples, we studied the VIMOS Public Extragalactic Redshift Survey (VIPERS) data and compared these results with the SDSS data. We have found that both FMR and its projection at z~0.6 to z~0 are not in agreement even when the data selection effects are carefully applied. This implies a small but statistically significant evolution of the FMR between z~0.6 to z~0 which needs to be taken into account in future studies.
To study the evolution at z>2, it is important to expand the studies also where spectroscopic data are lacking. The multi-wavelength observation in the NEP field could be, in addition to SDSS and VIPERS data, the perfect opportunity to extend the studies of the ``photometric'' metallicity and consequently the studies of the FMR at higher redshifts.