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arXiv · 2608.02754

A field-inspired derivation of open string amplitudes

Humberto Gomez·Renann Lipinski Jusinskas·Sitender Pratap Kashyap
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Abstract

We propose a new method for computing $N$-point tree-level open string amplitudes, inspired by the field-theoretical perturbiner framework and bypassing world-sheet moduli integration. The construction rests on a weak associativity condition for a point-split, on-shell product of string vertices, introducing a binary-tree prescription with all physical channels manifest. The output is a multi-parametric series representation of the partial amplitude that is amenable to mass-level truncation and, therefore, numerical implementation. Besides the Veneziano amplitude, automatically represented by a dual-channel series with one free parameter, we present its five-point generalization, involving two free parameters and matched against known results in the literature. Higher multiplicities are obtained via the same systematic branching, with no separate input.

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Humberto Gomez, Renann Lipinski Jusinskas, Sitender Pratap Kashyap. 2026-08-03. A field-inspired derivation of open string amplitudes. https://arxiv.org/abs/2608.02754

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