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arXiv · 1102.1821

Borcherds Algebras and N=4 Topological Amplitudes

Matthias R. Gaberdiel·Stefan Hohenegger·Daniel Persson
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Abstract

The perturbative spectrum of BPS-states in the E_8 x E_8 heterotic string theory compactified on T^2 is analysed. We show that the space of BPS-states forms a representation of a certain Borcherds algebra G which we construct explicitly using an auxiliary conformal field theory. The denominator formula of an extension G_{ext} \supset G of this algebra is then found to appear in a certain heterotic one-loop N=4 topological string amplitude. Our construction thus gives an N=4 realisation of the idea envisioned by Harvey and Moore, namely that the `algebra of BPS-states' controls the threshold corrections in the heterotic string.

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Matthias R. Gaberdiel, Stefan Hohenegger, Daniel Persson. 2011-02-09. Borcherds Algebras and N=4 Topological Amplitudes. https://doi.org/10.1007/jhep06(2011)125

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