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arXiv · 1410.6708

Characteristic classes for curves of genus one

Lenny Taelman
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Abstract

We compute the cohomology of the stack M_1 with coefficients in Z[1/2], and in low degrees with coefficients in Z. Cohomology classes on M_1 give rise to characteristic classes, cohomological invariants of families of curves of genus one. We prove a number of vanishing results for those characteristic classes, and give explicit examples of families with non-vanishing characteristic classes.

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Lenny Taelman. 2014-10-24. Characteristic classes for curves of genus one. https://doi.org/10.1307/mmj%2F1441116661

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