Mathematical modeling of point defects in materials science

We survey some recent mathematical works we have contributed to that are related to the modeling of defects in materials science at different scales. We em-phasize the similarities (need of a reference, often periodic system; renormalization procedure; etc) shared by models arising in different contexts. Our illustrative examples are taken from electronic structure models, atomistic models, homoge-nization problems. The exposition is pedagogic and deliberately kept elementary. Both theoretical and numerical aspects are addressed. ∗Invited article for a special issue of M3AS. ha l-