English

Two-point tree-level string amplitudes as AdS transition amplitudes

High Energy Physics - Theory 2025-07-09 v3

Abstract

We compute the two-point open string and closed string amplitudes at tree level and show that, in a 't Hooft-like limit, they take a form structurally analogous to boundary-to-boundary transition amplitudes of a scalar field in Euclidean AdS space. Interestingly, while both amplitudes yield equivalent expressions, the associated 't Hooft couplings are defined by different worldsheet curvatures-geodesic for the disk and Gaussian for the sphere-suggesting a possible geometric aspect of open/closed string duality.

Keywords

Cite

@article{arxiv.2505.07358,
  title  = {Two-point tree-level string amplitudes as AdS transition amplitudes},
  author = {Pongwit Srisangyingcharoen and Jongruk Pukdee},
  journal= {arXiv preprint arXiv:2505.07358},
  year   = {2025}
}
R2 v1 2026-06-28T23:29:15.642Z