La condition “ constant” est une condition numérique d’équisingularité introduite par B. Teissier. Celui-ci a démontré dans (Astérisque, 7 & 8 (1973) II. Théorème 3.9) que cette condition implique les conditions de Whitney, nous montrons ici la réciproque.
To every morphism of differential graded Lie algebras we associate a functors of artin rings whose tangent and obstruction spaces are respectively the first and second cohomology group of the suspension of the mapping cone of . Such construction applies to Hilbert and Brill-Noether functors and allow to prove with ease that every higher obstruction to deforming a smooth submanifold of a Kähler manifold is annihilated by the semiregularity map.