In the DFT context, symmetry breaking might be seen as a signature of the approximate nature of a given exchange-correlation functional. Taking as an example the dissociation of the hydrogen molecule discussed in contribution (3.6.1), one might expect to never see any symmetry breaking if one employs the exact exchange-correlation functional within Kohn-Sham DFT, which is true for the Hubbard dimer. Thus, the ability of a given functional not to break the (spin and spatial) symmetries could be potentially seen as a diagnostic of its quality.