On a complexification of the moduli space of Bohr - Sommerfeld lagrangian cycles

TL;DR

This paper constructs a complex structure on a space related to Bohr-Sommerfeld Lagrangian cycles, providing a complexification of their moduli space, with implications for geometric quantization.

Contribution

It introduces a complex structure on the moduli space of Bohr-Sommerfeld Lagrangian cycles, extending it to a complexified space with new geometric insights.

Findings

The differential of the projection p is an isomorphism.

The space U_SBS admits a natural complex structure.

The moduli space B_S is complexified via a suitable section.

Abstract

In the previous papers we present a construction of the set ${\cal U}_{SBS}$ in the direct product ${\cal B}_S \times \mathbb{P} \Gamma (M, L)$ of the moduli space of Bohr - Sommerfeld lagrangian submanifolds of fixed topological type and the projectivized space of smooth sections of the prequantization bundle $L \to M$ over a given compact simply connected symplectic manifold $M$. Canonical projections $p: {\cal U}_{SBS} \to \mathbb{P} \Gamma (M, L)$ and $q: {\cal U}_{SBS} \to {\cal B}_S$ are studied in the present text: first, we show that the differential ${\rm d} p$ at a given point is an isomorphism, which implies that a natural complex structure can be defined on ${\cal U}_{SBS}$; second, the projection $q: {\cal U}_{SBS} \to {\cal B}_S$ splits as the combination ${\cal U}_{SBS} \to T {\cal B}_S \to {\cal B}_S$ such that the fibers of the first map are complex subsets in ${\cal U}_{SBS}$. This implies that an appropriate section of the first map should define a complex structure on $T {\cal B}_S$; therefore it can be seen as a complexification of the moduli space ${\cal B}_S$. The construction can be exploited in the Lagrangian approach to Geometric Quantization