2017/03/02 by Baird, Thomas John
#14P25 #32L05 #FOS: Mathematics #Symplectic Geometry (math.SG)
paper · doi:10.48550/arxiv.1703.00778
Let (Σ,τ) denote a Riemann surface of genus g ≥ 2 equipped with an anti-holomorphic involution τ. In this paper we study the topology of the moduli space M(r,ξ)τ of stable Real vector bundles over (Σ,τ) of rank r and fixed determinant ξ of degree coprime to r. We prove that M(r,ξ)τ is an orientable and monotone Lagrangian submanifold of the complex moduli space M(r,ξ) so it determines an object in the appropriate Fukaya category. We derive recursive formulas for the mod 2 Betti numbers of M(r,ξ)τ and compute mod p Betti numbers for odd p through a range of degrees. We deduce that if r is even and g >>0, then M(r,ξ)τ and M(r,ξ')τ have non-isomorphic cohomology groups unless ξ and ξ' have equivalent Stieffel-Whitney classes modulo automorphisms of (Σ,τ). If r is even, and g>>0 is even, we prove that the Betti numbers of M(r,ξ)τ distinguish topological types of (Σ, τ; ξ). If r=2 and g is odd, we compute all mod p Betti numbers of M(2,ξ)τ. MR 32L05, 14P25.