Deformations of coisotropic submanifolds in locally conformal symplectic manifolds

Abstract: In this paper, we study deformations of coisotropic submanifolds in a locally conformal symplectic manifold. Firstly, we derive the equation that governs $C^\infty$ deformations of coisotropic submanifolds and define the corresponding $C^\infty$-moduli space of coisotropic submanifolds modulo the Hamiltonian isotopies. Secondly, we prove that the formal deformation problem is governed by an $L_\infty$-structure which is a $\frak b$-deformation of strong homotopy Lie algebroids introduced in Oh and Park (2005) in the symplectic context. Then we study deformations of locally conformal symplectic structures and their moduli space, and the corresponding bulk deformations of coisotropic submanifolds. Finally we revisit Zambon's obstructed infinitesimal deformation (Zambon, 2002) in this enlarged context and prove that it is still obstructed.