Abstract
After showing that a covering space of surface bundles over \(S^1\) factors as a ‘covering of fibers’ followed by a ‘power covering’, we prove that, for torus bundles, there are fiber coverings that lower the genus only for bundles that are double branched coverings of the 3-sphere, and for the same family, bundles that double cover \(S^3\), we show that power coverings do not lower Heegaard genus.
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To Professor María Teresa Lozano on the occasion of her 70th birthday.
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Núñez, V., Ramírez-Losada, E. & Remigio-Juárez, J. Genera of coverings of torus bundles. RACSAM 112, 811–827 (2018). https://doi.org/10.1007/s13398-017-0483-7
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DOI: https://doi.org/10.1007/s13398-017-0483-7