UV/IR Mixing in Noncommutative Field Theory via Open String Loops
Abstract
Description
We explicitly evaluate one-loop (annulus) planar and nonplanar open string amplitudes in the presence of the background NS-NS two-form field. In the decoupling limit of Seiberg and Witten, we find that the nonplanar string amplitudes reproduce the UV/IR mixing of noncommutative field theories. In particular, the investigation of the UV regime of the open string amplitudes shows that certain IR closed string degrees of freedom survive the decoupling limit as previously predicted from the noncommutative field theory analysis. These degrees of freedom are responsible for the quadratic, linear and logarithmic IR singularities when the D-branes embedded in space-time have the codimension zero, one and two, respectively. The analysis is given for both bosonic and supersymmetric open strings.
15 pages, 3 eps figures; v2. An error in gauge boson amplitudes corrected and now they are identical to the ones in hep-th/0003180
15 pages, 3 eps figures; v2. An error in gauge boson amplitudes corrected and now they are identical to the ones in hep-th/0003180