English

String theory in the infrared

High Energy Physics - Theory 2026-04-28 v1

Abstract

I briefly summarize a recent research program aiming to probe the landscape of low-energy phases of string theory from a global perspective. Borrowing conceptual lessons from the swampland program, I will discuss how the effective theories of gravity produced by low-energy string theory are far from generic; rather, their infrared data is connected by universal scaling relations which become non-trivial in species limits. In particular, a worldsheet analysis reveals that higher-derivative Wilson coefficients and the vacuum energy exhibit UV/IR relations which are invisible from the viewpoint of effective field theory, leading to parametric inequalities which take the form of holographic bounds. This lends a more solid theoretical support to swampland-motivated phenomenological scenarios, and to the broader hopes of extracting less direct, but empirically accessible, signatures of string theory from cosmological observations.

Keywords

Cite

@article{arxiv.2604.22916,
  title  = {String theory in the infrared},
  author = {Ivano Basile},
  journal= {arXiv preprint arXiv:2604.22916},
  year   = {2026}
}

Comments

17 pages, 5 figures. Contribution to the proceedings of Corfu Summer Institute 2025 "School and Workshops on Elementary Particle Physics and Gravity" (CORFU2025), 27 April - 28 September, 2025, Corfu, Greece

R2 v1 2026-07-01T12:34:24.555Z