  We discuss the duality in three dimensional quantum field theory at infrared
limit. The starting point is to use a conjecture of a duality between the free
fermion and the interacting scalar field theories at the Wilson-Fisher fixed
point. The conjecture is useful for deriving various dualities in three
dimensions to obtain a duality web. The study is also interesting for
understanding the dualities, or equivalence of different theories from the
perspective of the renormalization group flow. We first discuss the
"derivation" without losing the holonomy. Furthermore, we also derive these
dualities from the mean-field study, and consider the extension of the
conjecture or dualities at finite temperature.
