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Harmonic metrics and connections with irregular singularities

Claude Sabbah
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Abstract

We identify the holomorphic de Rham complex of the minimal extension of a meromorphic vector bundle with connexion on a compact Riemann surface X with the L^2 complex relative to a suitable metric on the bundle and a complete metric on the punctured Riemann surface. Applying results of C. Simpson, we show the existence of a harmonic metric on this vector bundle, giving the same L^2 complex. As a consequence, we obtain a Hard Lefschetz-type theorem.

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Claude Sabbah. 1999-05-06. Harmonic metrics and connections with irregular singularities. https://arxiv.org/abs/math/9905039

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