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Computing $ u$-invariants of Joyces compact $G_2$-manifolds

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 نشر من قبل Christopher Scaduto
 تاريخ النشر 2020
  مجال البحث
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Crowley and Nordstr{o}m introduced an invariant of $G_2$-structures on the tangent bundle of a closed 7-manifold, taking values in the integers modulo 48. Using the spectral description of this invariant due to Crowley, Goette and Nordstr{o}m, we compute it for many of the closed torsion-free $G_2$-manifolds defined by Joyces generalized Kummer construction.



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