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arXiv · hep-th/9207113

Gravitino one-loop contribution to Planckian Scattering

A. Bellini·M. Ademollo·M. Ciafaloni
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Abstract

Corrections to the semiclassical approximation in nearly forward Planckian energy collisions are here reconsidered. Starting from the one-loop superstring amplitude, we are able to disentangle the first subleading high-energy contribution at large impact parameters, and we thus directly compute the one-loop correction to the superstring eikonal. We finally argue, on the basis of analyticity and unitarity, that gravitinos do not contribute at all to the large distance two-loop ACV correction, which thus acquires a universal ``classical'' interpretation.

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A. Bellini, M. Ademollo, M. Ciafaloni. 1992-07-31. Gravitino one-loop contribution to Planckian Scattering. https://doi.org/10.1016/0550-3213(93)90238-k

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