Abstract:
In this thesis we analyze the properties of asymptotically flat three dimensional space-times with extended supersymmetry. We then give the construction of the asymptotic algebra for the extended supersymmetric cases by two different methods: first by Inönü-Wigner contraction of two copies of superconformal algebra, and then by an asymptotic symmetry analysis. We thereafter go on to explore important physical properties like energy bounds and generic gravity solutions. Finally, we construct the free field realizations of the (super) BMS 3 systems, which may be an interesting step towards understanding flat holography.