Abstract
The (reduced) Burau representation V n of the braid group B n is obtained from the action of B n on the homology of an infinite cyclic cover of the disc with n punctures. In this paper, we calculate H *(B n ; V n ). Our topological calculation has the following arithmetic interpretation (which also has different algebraic proofs): the expected number of points on a random superelliptic curve of a fixed genus over F q is q.
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Chen, W. Homology of braid groups, the Burau representation, and points on superelliptic curves over finite fields. Isr. J. Math. 220, 739–762 (2017). https://doi.org/10.1007/s11856-017-1534-7
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DOI: https://doi.org/10.1007/s11856-017-1534-7