English

Closed string theory without level-matching at the free level

High Energy Physics - Theory 2023-03-22 v2

Abstract

In its traditional form, the string field in closed string field theory is constrained by the level-matching condition, which is imposed beside the action. By analogy with the similar problem for the Ramond sector, it was understood by Okawa and Sakaguchi how to lift this condition and work with unconstrained field by introducing spurious free fields. These authors also pointed out that new backgrounds may exist thanks to a new gauge field which is trivial on flat space, but can generate fluxes on a toroidal background. In this paper, we perform a complete study of the free theory at the tachyonic and massless levels with the aim of setting the stage for studying backgrounds without level-matching.

Keywords

Cite

@article{arxiv.2209.05585,
  title  = {Closed string theory without level-matching at the free level},
  author = {Harold Erbin and Maxime Médevielle},
  journal= {arXiv preprint arXiv:2209.05585},
  year   = {2023}
}

Comments

31 pages; v2: minor updates, published version

R2 v1 2026-06-28T01:09:59.948Z