  Chirality induced spin selectivity, discovered about two decades ago in
helical molecules, is a non-equilibrium effect that emerges from the interplay
between geometrical helicity and spin-orbit interactions. Several model
Hamiltonians building on this interplay have been proposed and while these can
yield spin-polarized transport properties that agrees with experimental
observations, they simultaneously depend on unrealistic values of the
spin-orbit interaction parameters. It is likely, however, that a common deficit
originates from the fact that all these models are uncorrelated, or,
single-electron theories. Therefore, chirality induced spin selectivity is,
here, addressed using a many-body approach, which allows for non-equilibrium
conditions and a systematic treatment of the correlated state. The intrinsic
molecular spin-polarization increases by two orders of magnitudes, or more,
compared to the corresponding result in the uncorrelated model. In addition,
the electronic structure responds to varying external magnetic conditions
which, therefore, enables comparisons of the currents provided for different
spin-polarizations in one of the (or both) leads between which the molecule is
mounted. Using experimentally feasible parameters and room temperature, the
obtained normalized difference between such currents may be as large as 5 - 10
% for short molecular chains, clearly suggesting the vital importance of
including electron correlations when searching for explanations of the
phenomenon.
