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arXiv · 1111.6303

The A-infinity algebra of an Elliptic Curve and the j-invariant

Robert Fisette
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Abstract

We compute reduced Hochschild cohomology of B = Ext\star (O \oplus L, O \oplus L), where O is the structure sheaf of an elliptic curve and L is a line bundle of degree 1. The result suggests an A-infinity equivalence between the A-infinity structure computed for B in [1] and a structure in which m_3=m_4=m_5=0. We see that the j-invariant of the curve is explicitly related to this new structure.

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Robert Fisette. 2011-11-27. The A-infinity algebra of an Elliptic Curve and the j-invariant. https://arxiv.org/abs/1111.6303

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