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Multiloop Superstring Amplitudes from Non-Minimal Pure Spinor Formalism

Nathan Berkovits·Nikita Nekrasov
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Abstract

Using the non-minimal version of the pure spinor formalism, manifestly super-Poincare covariant superstring scattering amplitudes can be computed as in topological string theory without the need of picture-changing operators. The only subtlety comes from regularizing the functional integral over the pure spinor ghosts. In this paper, it is shown how to regularize this functional integral in a BRST-invariant manner, allowing the computation of arbitrary multiloop amplitudes. The regularization method simplifies for scattering amplitudes which contribute to ten-dimensional F-terms, i.e. terms in the ten-dimensional superspace action which do not involve integration over the maximum number of $θ$'s.

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Nathan Berkovits, Nikita Nekrasov. 2006-09-02. Multiloop Superstring Amplitudes from Non-Minimal Pure Spinor Formalism. https://doi.org/10.1088/1126-6708%2F2006%2F12%2F029

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