  Instantons, monopoles and vortices have become paradigms of topological
structures in field theory and quantum mechanics, with important applications
in particle physics, astrophysics, condensed matter physics and mathematics. We
have discussed here the self-dual Chern-Simons theory specially in (2+1)
dimensions. we start with a relevant topological quantum mechanical model (such
as Landau problem consisting of two basic chiral oscillators) and extrapolate
the analysis to (2+1)dimensional vector field theory. Aspects of selfdual
symmetry in topologically massive gravity model were also considered using
three different approaches. We have demonstrated how duality symmetric (or
chiral) actions are already present in the quantum mechanical examples such as
in usual harmonic oscillator. Using the chiral oscillator form, we will briefly
develop the key concepts of the soldering mechanism. We have also discussed the
non commutative property of such quantum models. Models involving higher order
derivative of Abelian CS-term in (2+1)dimensions, specially the leading third
order derivative Chern-Simons term were studied; Inclusion of this term with
usual Maxwell term or with CS term or to both of these terms reveals many
interesting observations. We have also described the spin 2 tensor models which
appear in discussions of linearised gravity in (2 + 1) dimensions.
