Invariants Associated to Orthogonal $ε$-constants

Darren Glass

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Invariants Associated to Orthogonal $ε$-constants

Darren Glass

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Abstract

In this paper we use the theory of $ε$-constants associated to tame finite group actions on arithmetic surfaces to define a Brauer group invariant $μ(\X,G,V)$ associated to certain symplectic motives of weight one. We then discuss the relationship between this invariant and $w_2(π)$, the Galois theoretic invariant associated to tame covers of surfaces.

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Darren Glass. 2002-11-19. Invariants Associated to Orthogonal $ε$-constants. https://arxiv.org/abs/math/0210248

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