Classical string profile for a class of DDF amplitudes

Diptarka Das; Santanu Mandal; Anurag Sarkar

doi:10.1016/j.physletb.2025.139971

paper

Classical string profile for a class of DDF amplitudes

arXiv:2506.23974 · doi:10.1016/j.physletb.2025.139971

Abstract

In the critical bosonic string theory, we explicitly evaluate the three point scattering amplitude at tree level, of a photon with two massive higher spins. The massive excitations belong to states of the form $A_{- r_{1}}^{s_{1}} A_{- r_{2}}^{s_{2}}$ where $A_{- n}$ is a DDF creation operator. Next, we take the infinite ``spin'' limit to arrive at the classical string dynamics. We find a rotating ``floppy'' string lying mostly on a plane which develops a transverse kink.

23 pages, 7 figures, published version