Abstract
For a Poisson manifold $M$ we develop systematic methods to compute its Picard group $\mathrm{Pic}(M)$, i.e., its group of self Morita equivalences. We establish a precise relationship between $\mathrm{Pic}(M)$, and the group of gauge transformations up to Poisson diffeomorphisms showing, in particular, that their connected components of the identity coincide; this allows us to introduce the Picard Lie algebra of $M$ and to study its basic properties. Our methods lead to the proof of a conjecture from “Poisson sigma models and symplectic groupoids, in Quantization of Singular Symplectic Quotients” [A.S. Cattaneo, G. Felder, Progress in Mathematics 198 (2001), 41] stating that $\mathrm{Pic}(\mathfrak{g}^*)$, for any compact simple Lie algebra agrees with the group of outer automorphisms of $\mathfrak{g}$.
Funding Statement
HB has had the support of Faperj, and RLF is partially supported by NSF grants DMS 1308472 and DMS 1405671. Both authors acknowledge the support of a Capes/Brazil–FCT/Portugal cooperation grant and the Ciências Sem Fronteiras program sponsored by CNPq.
Citation
Henrique Bursztyn. Rui Loja Fernandes. "Picard groups of Poisson manifolds." J. Differential Geom. 109 (1) 1 - 38, May 2018. https://doi.org/10.4310/jdg/1525399215