Let M-n a closed, connected manifold, n greater than or equal to 6. Denote
by Nov(M) and Nov(st)(M) the minimal number of zeros of a generic closed on
e-form defined on M, resp. the minimal number of zeros of a generic closed
one-form on M x R-k which is almost quadratic at infinity.
Under an assumption on the Bieri-Neumann-Strebel and Bieri-Renz invariants
of pi(n), we show the implication Nov(st) = 0 => Nov = 0. If we drop this a
ssumption, the implication above turns out to be false in general. In fact,
our assumption is closely related to the implication FP2 => F-2, therefore
, it's in some sense optimal.
Applications in Novikov homology theory and in symplectic topology are give
n. (C) 2000 Editions scientifiques et medicales Elsevier SAS.