The connections among galaxies , the dark matter halos where they form and the properties of the large-scale Cosmic Web still need to be completely disentangled .
We use the cosmological hydrodynamical simulation TNG100 of the IllustrisTNG suite to quantify the effects played by the large-scale density field and the Cosmic Web morphology on the relation between halo mass and galaxy stellar mass .
We select objects with total dynamical mass in the range \geq 6.3 \times 10 ^ { 10 } h ^ { -1 } M _ { \odot } up to a few 10 ^ { 14 } h ^ { -1 } M _ { \odot } between redshift z = 4 and redshift z = 0 .
A Cosmic Web class ( knot , filament , sheet , void ) is assigned to each region of the volume using a density field deformation tensor-based method .
We find that galaxy stellar mass strongly correlates with total dynamical mass and formation time , and more weakly with large-scale overdensity and Cosmic Web class .
The latter two quantities correlate with each other , but are not entirely degenerate .
Furthermore , we find that at fixed halo mass , galaxies with stellar mass lower than the median value are more likely to be found in voids and sheets , whereas galaxies with stellar mass higher than the median are more likely to be found in filaments and knots .
Finally , we find that the dependence on environment is stronger for satellites than for centrals , and discuss the physical implications of these results .