Exotic 4-manifolds with signature zero

R. Inanc Baykur; Noriyuki Hamada

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arXiv · 2305.10908

Exotic 4-manifolds with signature zero

R. Inanc Baykur·Noriyuki Hamada

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Abstract

We produce infinitely many distinct irreducible smooth 4-manifolds homeomorphic to #(2m+1)(CP^2 # -CP^2) and #(2n+1)(S^2 x S^2), respectively, for each m>3 and n>4. These provide the smallest exotic closed simply connected 4-manifolds with signature zero known to date, and in each one of these homeomorphism classes, we get minimal symplectic 4-manifolds. Our novel exotic 4-manifolds are derived from fairly special small Lefschetz fibrations we build via positive factorizations in the mapping class group, with spin and non-spin monodromies.

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R. Inanc Baykur, Noriyuki Hamada. 2023-05-18. Exotic 4-manifolds with signature zero. https://arxiv.org/abs/2305.10908

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