  We derive general closed-form analytical expressions for the finite-energy
one- and two-electron spectral-weight distributions of an one-dimensional
correlated metal with on-site electronic repulsion. Our results also provide
general expressions for the one- and two-atom spectral functions of a
correlated quantum system of cold fermionic atoms in a one-dimensional optical
lattice with on-site atomic repulsion. In the limit of zero spin density our
spectral-function expressions provide the correct zero-spin density results.
Our results reveal the dominant non-perturbative microscopic many-particle
mechanisms behind the exotic spectral properties observed in
quasi-one-dimensional metals and correlated systems of cold fermionic atoms in
one-dimensional optical lattices.
