Massive Fields and the 2D String

TL;DR

This paper investigates the first massive level of 2D closed bosonic string theory, deriving free-field equations, finding solutions in a linear-dilaton background, and analyzing tachyon scattering, supporting the connection to the c=1 matrix model.

Contribution

It derives free-field equations for the massive string level in 2D and explores their solutions and scattering, linking 2D string theory to the c=1 matrix model.

Findings

Derived free-field equations for the massive string level.

Found solutions in a flat linear-dilaton background.

Supported the equivalence between 2D string theory and the c=1 matrix model.

Abstract

The first massive level of closed bosonic string theory is studied. Free-field equations are derived by imposing Weyl invariance on the world sheet. A two-parameter solution to the equation of motion and constraints is found in two dimensions with a flat linear-dilaton background. One-to-one tachyon scattering is studied in this background. The results support Dhar, Mandal and Wadia's proposal that 2D critical string theory corresponds to the c=1 matrix model in which both sides of the Fermi sea are excited.