Leaves and trajectories for schemes. Applications.
Institute of Mathematical Sciences, Chennai.
We develope new tools for schemes, namely leaves and trajectories and use it for two applications: 1) we compare two sheaves over the differential spectrum of a differential ring A 2) we geometrize and generalize a lemma of differential Galois theory. This generalization leads us to study the issue of the space of leaves of a scheme endowed with a vector field.