... BOLLOBAS, W. FULTON, A. KATOK, F. KIRWAN, P. SARNAK 150 Harmonic maps, conservation laws and moving frames Second edition 4 Geometric and analytic setting and for the energy density (1.4)ee2vg(φ)=e−2veg(φ). ... weakly harmonic maps, or their regularity. This is an opportunity to exploresome ideas and methods (symmetries, compensation phenomena, the useof moving frames and of Coulomb moving frames) , ... recently in the reg-ularity theory of harmonic maps, and are the companion ingredients tothe conservation laws. The limitation of techniques which use conservation laws is that sym-metric variational...