Relating harmonic and projective descriptions of N=2 nonlinear sigma models

Understand

Recent papers have established the relationship between projective superspace and a complexified version of harmonic superspace.

• We extend this construction to the case of general nonlinear sigma models in both frameworks.
• Using an analogy with Hamiltonian mechanics, we demonstrate how the Hamiltonian structure of the harmonic action and the symplectic structure of the projective action naturally arise from a single unifying action on a complexified version of harmonic superspace.
• This links the harmonic and projective descriptions of hyperkahler target spaces.