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Generic global generation for unitary local systems on curves (parabolic case)

Show that for g≥3 and a unitary representation \rho: \pi_1(\Sigma_{g,n})\to U(r), for a generic complex structure X with compactification \overline{X} and boundary D, the associated parabolic bundle \widehat{\mathscr{E}_0\otimes \omega_{\overline{X}}(D)} is generically generated by global sections.

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Background

This conjecture is a key geometric input toward big monodromy and vanishing theorems; it predicts generic global generation for twists of parabolic bundles arising via the Mehta–Seshadri correspondence from unitary monodromy. Its verification would imply strong consequences such as the Putman–Wieland conjecture.

References

Conjecture [ggg conjecture] Let $g\geq 3$, and let $$\rho: \pi_1(\Sigma_{g,n})\to U(r)$$ be a unitary representation. Fix a generic complex structure $X$ on $\Sigma_{g,n}$, with $\overline{X}$ the corresponding compact Riemann surface, and $D=\overline{X}\setminus X$, and let $\mathscr{E}\star$ be the corresponding parabolic bundle. Then $\widehat{\mathscr{E}_0\otimes \omega{\overline{X}}(D)}$ is generically generated by global sections.

Motives, mapping class groups, and monodromy (2409.02234 - Litt, 3 Sep 2024) in Conjecture (ggg conjecture), Section 6.3.1