The use of 2-component SUSY is more convenient and mathematically elegant because it allows for the simplification of equations and calculations. It also provides a better description of the physical states in the theory.
In 4-component SUSY, the spinor representations are complex, making the symmetry more difficult to work with. However, in 2-component SUSY, the spinor representations are real, simplifying the calculations and making the symmetry easier to manipulate.
2-component SUSY is closely related to superfields, which are mathematical objects that describe the different components of a supersymmetric theory. The use of 2-component SUSY allows for a more compact and efficient representation of these superfields.
No, 2-component SUSY is not applicable to all supersymmetric theories. It is mainly used in theories with extended supersymmetry, such as N=2 or N=4, where a higher number of components would lead to unnecessary complexity.
One potential drawback to using 2-component SUSY is that it may not fully capture all the intricacies of the supersymmetric theory. Some calculations and predictions may require the use of 4-component SUSY for a more accurate representation. However, the use of 2-component SUSY is still a valuable and widely used tool in studying supersymmetric theories.