Mean-field description of high-spin states

Recent high-spin observations reveal entirely new modes of collective rotational motion and the existence of novel symmetries and spontaneous symmetry breaking phenomena, uncovering hitherto unexploited coupling schemes of intrinsic and collective degrees of freedom. It continues to stimulate the theoretical progress in the field, which clearly turns towards a microscopic description based on self-consistent approaches using either an effective non-relativistic Hamiltonian or an effective relativistic Lagrangian. New coupling schemes call not only for symmetry unrestricted mean-field theories, but also for extensions going beyond the mean-field. The progress in the development of these theoretical methods is discussed in this review.