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arXiv · hep-th/0603165

R^4, purified

Giuseppe Policastro·Dimitrios Tsimpis
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Abstract

We derive, using the pure-spinor formalism, the complete -- including the fermions -- four-point effective action of both type II superstrings to all orders in $α'$, at tree level in string loops. We find that, in the quartic-field approximation, the supergravity Lagrangian can be thought of as the tensor product, in a suitable sense, of two copies of the superYang-Mills Lagrangian in ten dimensions. The NS-NS three-form enters the supergravity Lagrangian through a modified connection with torsion. As a byproduct, we derive the complete, i.e. to all orders in the $θ$-expansion, closed-string vertex operator in a flat target-space background.

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Giuseppe Policastro, Dimitrios Tsimpis. 2006-04-06. R^4, purified. https://doi.org/10.1088/0264-9381%2F23%2F14%2F012

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