The effective string spectrum in the orthogonal gauge

TL;DR

This paper computes the leading correction to the string spectrum using the Polchinski-Strominger effective action in the orthogonal gauge, confirming its consistency with previous static gauge results and enhancing understanding of gauge relations.

Contribution

It provides the first explicit calculation of the leading correction to the string spectrum within the orthogonal gauge framework, validating the Polchinski-Strominger approach.

Findings

The correction matches previous static gauge results.

Confirms the consistency of the orthogonal gauge analysis.

Supports the validity of the Polchinski-Strominger effective action.

Abstract

The low-energy effective action on long string-like objects in quantum field theory, such as confining strings, includes the Nambu-Goto action and then higher-derivative corrections. This action is diffeomorphism-invariant, and can be analyzed in various gauges. Polchinski and Strominger suggested a specific way to analyze this effective action in the orthogonal gauge, in which the induced metric on the worldsheet is conformally equivalent to a flat metric. Their suggestion leads to a specific term at the next order beyond the Nambu-Goto action. We compute the leading correction to the Nambu-Goto spectrum using the action that includes this term, and we show that it agrees with the leading correction previously computed in the static gauge. This gives a consistency check for the framework of Polchinski and Strominger, and helps to understand its relation to the theory in the static gauge.