2021/07/22 by Biswas, Indranil, Looijenga, Eduard
#14J42 #53B10 #53C07 #57R20 #Algebraic Geometry (math.AG) #Complex Variables (math.CV) #FOS: Mathematics
paper · doi:10.48550/arxiv.2107.10482
Let f:X→ S be a proper holomorphic submersion of complex manifolds and G a complex reductive linear algebraic group with Lie algebra \mathfrakg. Assume also given a holomorphic principal G-bundle P over X which is endowed with a holomorphic connection ∇ relative to f that is flat (this to be thought of as a holomorphic family of compact complex manifolds endowed with a holomorphic principal G-bundle with flat connection). We show that a refinement of the Chern-Weil homomorphism yields a graded algebra homomorphism ℂ[\mathfrakg]G→ \bigoplusn≥ 0 H0(S, ΩnS,cl⊗ Rnf_*ℂ), where ΩnS,cl stands for the sheaf of closed holomorphic n-forms on S. If the fibers of f are compact Riemann surfaces and we take as our invariant the Killing form, then we recover Goldman's closed holomorphic 2-form on the base S.