Light cone quantization and interactions of a new closed bosonic string inspired to D1 string

TL;DR

This paper quantizes the bosonic D1 string using light cone methods, revealing sector-dependent spectra and couplings, with implications for understanding string interactions and gauge field dynamics.

Contribution

It introduces a sector decomposition of the D1 string spectrum with dynamical U(1) gauge fields, showing sectors do not interact and share the same spectrum after rescaling.

Findings

Sectors characterized by U(1) Wilson line momentum do not interact.

Each sector has the same spectrum as the usual bosonic string after rescaling.

The relative string coupling constants are determined for different sectors.

Abstract

We quantize the bosonic part of the D1 string with closed boundary conditions on the light cone and we consider the U(1) worldsheet gauge field a dynamical variable. We compute also 3-Reggeon vertex by the overlapping technique. We find that the Fock space is the sum of sectors characterized by the momentum of the U(1) Wilson line and that these sectors do not interact among them. Each sector has exactly the same spectrum of the usual bosonic string when expressed in properly sector dependent rescaled variables. Rescaling is forced by factorization of the string amplitudes. We are also able to determine the relative string coupling constant of the different sectors. It follows a somewhat unexpected picture in which the effective action is always the same independently on the sector but string amplitudes are only the same when expressed in sector dependent rescaled variables.