Semiclassical partition function for strings dual to Wilson loops with small cusps in ABJM

TL;DR

This paper calculates the one-loop partition function for strings in AdS4×CP3 with boundary cusps, confirming a theoretical proposal for the Bremsstrahlung function at strong coupling in ABJM theory.

Contribution

It provides the first explicit one-loop string partition function computation for cusped Wilson lines in ABJM, verifying a key theoretical prediction.

Findings

Agreement with Lewkowycz and Maldacena's proposal for the Bremsstrahlung function.

Validation of the string theory calculation for both 1/2 BPS and 1/6 BPS Wilson lines.

Explicit computation of vacuum energies for on-shell modes in this context.

Abstract

We compute the 1-loop partition function for strings in $AdS_4\times\mathbb{CP}^3$, whose worldsheets end along a line with small cusp angles in the boundary of AdS. We obtain these 1-loop results in terms of the vacuum energy for on-shell modes. Our results verify the proposal by Lewkowycz and Maldacena in arXiv:1312.5682 for the exact Bremsstrahlung function up to the next to leading order in the strong coupling expansion. The agreement is observed for cusps distorting either the 1/2 BPS or the 1/6 BPS Wilson line.