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On the Zero-Slope Limit of the Compactified Closed Bosonic String

Raffaele Marotta·Franco Pezzella
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Abstract

In the framework of the compactified closed bosonic string theory with the extra spatial coordinates being circular with radius $R$, we perform both the zero-slope limit and the $R \rightarrow 0$ limit of the tree scattering amplitude of four massless scalar particles. We explicitly show that this double limit leads to amplitudes involving scalars which interact through the exchange of a scalar, spin 1 and spin 2 particle. In particular, this latter case reproduces the same result obtained in linearized quantum gravity.

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Raffaele Marotta, Franco Pezzella. 1993-12-07. On the Zero-Slope Limit of the Compactified Closed Bosonic String. https://doi.org/10.1103/physrevd.50.2779

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