01059nas a2200133   4500008004300000245007500043210007000118260001300188520062700201100002100828700001800849700002200867856003600889       1997                        en_Ud  00aKrichever maps, Faà di Bruno polynomials, and cohomology in KP theory0 aKrichever maps Faà di Bruno polynomials and cohomology in KP the  bSpringer3 aWe study the geometrical meaning of the Faa\\\' di Bruno polynomials in the context of KP theory. They provide a basis in a subspace W of the universal Grassmannian associated to the KP hierarchy. When W comes from geometrical data via the Krichever map, the Faa\\\' di Bruno recursion relation turns out to be the cocycle condition for (the Welters hypercohomology group describing) the deformations of the dynamical line bundle on the spectral curve together with the meromorphic sections which give rise to the Krichever map. Starting from this, one sees that the whole KP hierarchy has a similar cohomological meaning.1 aFalqui, Gregorio1 aReina, Cesare1 aZampa, Alessandro  uhttp://hdl.handle.net/1963/3539