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arXiv · 1907.01054

Unweighted Donaldson-Thomas theory of the banana 3-fold with section classes

Oliver Leigh
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Abstract

We further the study of the Donaldson-Thomas theory of the banana threefolds which were recently discovered and studied in [Bryan'19]. These are smooth proper Calabi-Yau threefolds which are fibred by Abelian surfaces such that the singular locus of a singular fibre is a non-normal toric curve known as a "banana configuration". In [Bryan'19] the Donaldson-Thomas partition function for the rank 3 sub-lattice generated by the banana configurations is calculated. In this article we provide calculations with a view towards the rank 4 sub-lattice generated by a section and the banana configurations. We relate the findings to the Pandharipande-Thomas theory for a rational elliptic surface and present new Gopakumar-Vafa invariants for the banana threefold.

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Oliver Leigh. 2019-07-01. Unweighted Donaldson-Thomas theory of the banana 3-fold with section classes. https://doi.org/10.1093/qmathj%2Fhaaa007

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