The geometric deformation of curved $L_\infty$ algebras and Lie algebroids

Abstract: We investigate the deformation of an $L_\infty$ structure that encodes the geometric information about a smooth vector bundle. We establish that this specific type of deformation endows the bundle with a Lie algebroid structure. Additionally, we compute the Atiyah class and Atiyah-Chern classes in the geometrically deformed case. The precise relationship between the first Atiyah-Chern class and the modular class is shown. In the case of action Lie algebroids, the Atiyah-Chern classes at the leading order are given by the equivariant Chern characters.