Abstract
Let E be a vector bundle over an irreducible projective variety X defined over an algebraically closed field. We give a necessary and sufficient condition for E to be a direct image of a vector bundle on an étale cover, of degree more than one, of X. In fact, we describe all possible ways E can be realized as a direct image. Given a connection D on E, a criterion is given for D to be induced by a connection on a vector bundle whose direct image, by an étale covering map of degree more than one, is E.
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Acknowledgements
The first-named author is supported by a J. C. Bose Fellowship. The last-named author was supported by SFB/TR 45 “Periods, moduli and arithmetic of algebraic varieties”, subproject M08-10 “Moduli of vector bundles on higher-dimensional varieties”.
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Biswas, I., Gangopadhyay, C. & Wong, M.L. Direct images of vector bundles and connections. Beitr Algebra Geom 60, 137–156 (2019). https://doi.org/10.1007/s13366-018-0410-x
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DOI: https://doi.org/10.1007/s13366-018-0410-x