Noncommutative Gauge Dynamics From The String Worldsheet

TL;DR

This paper demonstrates how string theory can reproduce one-loop photon amplitudes in noncommutative U(1) gauge theory, revealing insights into IR/UV singularities and their string-theoretic origins.

Contribution

It provides a string-theoretic derivation of one-loop noncommutative gauge theory amplitudes, clarifying the role of open strings and the nature of IR/UV singularities.

Findings

Reproduces one-loop photon amplitude from string theory

Shows IR/UV singularities are not simply from closed strings

Highlights the dominance of massless open strings in the decoupling limit

Abstract

We show how string theory can be used to reproduce the one-loop two-point photon amplitude in noncommutative U(1) gauge theory. Using a simple realization of the gauge theory in bosonic string theory, we extract from a string cylinder computation in the decoupling limit the exact one loop field theory result. The result is obtained entirely from the region of moduli space where massless open strings dominate. Our computation indicates that the unusual IR/UV singularities of noncommutative field theory do not come from closed string modes in any simple way.