Holomorphic submersions of locally conformally K\"ahler manifolds

Abstract

A locally conformally K\"ahler (LCK) manifold is a complex manifold covered by a K\"ahler manifold, with the covering group acting by homotheties. We show that if such a compact manifold X admits a holomorphic submersion with positive dimensional fibers at least one of which is of K\"ahler type, then X is globally conformally K\"ahler or biholomorphic, up to finite covers, to a Vaisman manifold (i.e. a mapping torus over a circle, with Sasakian fibre). As a consequence, we show that the product between a compact non-K\"ahler LCK and a compact K\"ahler manifold cannot carry a LCK metric.