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The alignment between halo spins and the cosmic web is still poorly understood despite being a widely studied topic. Here, we study this alignment within the context of tidal torque theory (TTT) and deviations from it. To this end, we analyze the evolution of the shape and spin direction of proto-haloes, i.e. of all the volume elements associated to a $z=0$ halo, with respect to the present-day filaments. We find that the major axis of proto-haloes undergoes a major change, from being strongly perpendicular to the filament spine in the initial conditions, to being preferentially aligned at the present time. In comparison, the spin orientation shows only a mild evolution: it starts slightly parallel to the filament spine, but the subsequent evolution, up to $z{sim}1$, gradually changes its orientation to preferentially perpendicular. In order to analyze these signals in the TTT framework, we split the haloes according to their net spin growth with respect to the median TTT expectation, finding a clear correlation with the spin--filament alignment. At the present time, haloes whose spin grew the most are the ones most perpendicular to the filament spine, while haloes whose spin grew below the median TTT expectation are typically more aligned. The dependence of spin directions on net spin growth is already present in the initial conditions, and gets further modified by late-time, $z<2$, evolution. Also, spin directions mildly deviate from the TTT predictions even at high redshift, indicating the need for extensions to the model.
The correlation between the spins of dark matter halos and the large-scale structure (LSS) has been studied in great detail over a large redshift range, while investigations of galaxies are still incomplete. Motivated by this point, we use the state-
We present that the spin$-$orbit alignment (SOA; i.e., the angular alignment between the spin vector of a halo and the orbital angular momentum vector of its neighbor) provides an important clue to how galactic angular momenta develop. In particular,
Contradictory results have been reported on the time evolution of the alignment between clusters and their Brightest Cluster Galaxy (BCG). We study this topic by analyzing cosmological hydro-simulations of 24 massive clusters with $M_{200}|_{z=0} gtr
We examine the properties and evolution of a simulated polar disc galaxy. This galaxy is comprised of two orthogonal discs, one of which contains old stars (old stellar disc), and the other, containing both younger stars and the cold gas (polar disc)
We study the evolution of the luminosity-to-halo mass relation of Luminous Red Galaxies (LRGs). We select a sample of 52 000 LOWZ and CMASS LRGs from the Baryon Oscillation Spectroscopic Survey (BOSS) SDSS-DR10 in the ~450 deg^2 that overlaps with im