Revealing the cosmic web dependent halo bias
  Halo bias is the one of the key ingredients of the halo models. It was shown
at a given redshift to be only dependent, to the first order, on the halo mass.
In this study, four types of cosmic web environments: clusters, filaments,
sheets and voids are defined within a state of the art high resolution $N$-body
simulation. Within those environments, we use both halo-dark matter
cross-correlation and halo-halo auto correlation functions to probe the
clustering properties of halos. The nature of the halo bias differs strongly
among the four different cosmic web environments we describe. With respect to
the overall population, halos in clusters have significantly lower biases in
the {$10^{11.0}\sim 10^{13.5}h^{-1}\rm M_\odot$} mass range. In other
environments however, halos show extremely enhanced biases up to a factor 10 in
voids for halos of mass {$\sim 10^{12.0}h^{-1}\rm M_\odot$}. Such a strong
cosmic web environment dependence in the halo bias may play an important role
in future cosmological and galaxy formation studies. Within this cosmic web
framework, the age dependency of halo bias is found to be only significant in
clusters and filaments for relatively small halos $\la 10^{12.5}\msunh$.
