$N$-point amplitudes for d=2 c=1 Discrete States from String Field Theory

TL;DR

This paper analyzes N-point off-shell tree amplitudes of discrete states in 2D gravity coupled to c=1 matter using string field theory, revealing pole structures and deriving an effective action from the string field framework.

Contribution

It introduces a method to extract residues of amplitudes using oscillator representation and derives an effective action directly from string field theory in a specific gauge.

Findings

Amplitudes exhibit characteristic pole structures.

Residues are generated by a simple effective action.

Effective action can be deduced from string field theory in a transversal-like gauge.

Abstract

Starting from string field theory for 2d gravity coupled to c=1 matter we analyze N-point off-shell tree amplitudes of discrete states. The amplitudes exhibit the pole structure and we use the oscillator representation to extract the residues. The residues are generated by a simple effective action. We show that the effective action can be directly deduced from a string field action in a special transversal-like gauge.