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arXiv · 1312.7197

The Ramond Sector of Heterotic String Field Theory

Hiroshi Kunitomo
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Abstract

We attempt to construct the full equations of motion for the Neveu-Schwarz and the Ramond sectors of the heterotic string field theory. Although they are non-polynomial also in the Ramond string field $\Psi$, we can construct them order by order in $\Psi$. Their explicit forms with the gauge transformations are given up to the next-to-next-to-leading order in $\Psi$. We also determine a subset of the terms to all orders. By introducing an auxiliary Ramond string field $\Xi$, we construct a covariant action supplemented with a constraint, which should be imposed on the equations of motion. We propose the Feynman rules and show how they reproduce well-known physical four-point amplitudes with external fermions.

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Hiroshi Kunitomo. 2013-12-27. The Ramond Sector of Heterotic String Field Theory. https://doi.org/10.1093/ptep/ptu032

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