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Niemeier lattices, smooth 4-manifolds and instantons

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 Added by Christopher Scaduto
 Publication date 2018
  fields
and research's language is English




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We show that the set of even positive definite lattices that arise from smooth, simply-connected 4-manifolds bounded by a fixed homology 3-sphere can depend on more than the ranks of the lattices. We provide two homology 3-spheres with distinct sets of such lattices, each containing a distinct nonempty subset of the rank 24 Niemeier lattices.



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