Novikov's theorem in higher dimensions?
Sushmita Venugopalan
TL;DR
The authors address whether Novikov-type rigidity extends to higher dimensions by constructing a 5-dimensional manifold $X^5$ with a smooth foliation and a strong symplectic form that violate the natural analogue of Novikov's theorem. They develop foliated symplectic Lefschetz fibrations as the core tool, adapting Gompf's construction to foliated bases and proving a local model near singular fibers with controlled fiber area. The main result is a counterexample: a strong symplectic foliation for which the map $\pi_1(\,\mathcal{F})\to\pi_1(X)$ is not injective and a transversal loop can be contractible in $X$, underscoring that rigidity in higher dimensions differs from the 3-manifold case. The work suggests a weaker Novikov-type constraint may hold in odd dimensions and highlights the continued rigidity of strong symplectic foliations, while contrasting them with weak symplectic foliations. Overall, the paper clarifies the limits of extending 3D rigidity phenomena to higher-dimensional foliations and introduces new foliated Lefschetz techniques to construct and analyze such counterexamples.
Abstract
Novikov's theorem is a rigidity result on the class of taut foliations on three-manifolds. For higher dimensional manifolds, foliations with a strong symplectic form have been suggested as the class of foliations having similar rigidity properties to taut foliations on three-manifolds. This leads to the natural question of whether strong symplectic foliations satisfy an analogue of Novikov's theorem. In this paper, we construct a five-dimensional manifold with a smooth foliation and a strong symplectic form that does not satisfy the expected analogue of Novikov's theorem. Our example is a foliated Lefschetz fibration.
