  We investigate finite temperature spin transport in one spatial dimension by
considering the spin-spin correlation function of the Hubbard model in the
limiting case of infinitely strong repulsion. We find that in the absence of
bias the transport is diffusive, and derive the spin diffusion constant. Our
approach is based on asymptotic analysis of a Fredholm determinant
representation. The obtained results are in agreement with Generalized
Hydrodynamics approach.
