A quantum check of AdS/dCFT

作者：Buhl Mortensen Isak; de Leeuw Marius; Ipsen Asger C; Kristjansen Charlotte; Wilhelm Matthias

来源：The Journal of High Energy Physics, 2017, 2017(1): 098.

DOI：10.1007/JHEP01(2017)098

• AdS-CFT Correspondence
• Supersymmetric gauge theory
• 1/N Expansion

We build the framework for performing loop computations in the defect version of N = 4 super Yang-Mills theory which is dual to the probe D5-D3 brane system with background gauge-field flux. In this dCFT, a codimension-one defect separates two regions of space-time with different ranks of the gauge group and three of the scalar fields acquire non-vanishing and space-time-dependent vacuum expectation values. The latter leads to a highly non-trivial mass mixing problem between different colour and flavour components, which we solve using fuzzy-sphere coordinates. Furthermore, the resulting space-time dependence of the theory's Minkowski space propagators is handled by reformulating these as propagators in an effective AdS(4). Subsequently, we initiate the computation of quantum corrections. The one-loop correction to the one-point function of any local gauge-invariant scalar operator is shown to receive contributions from only two Feynman diagrams. We regulate these diagrams using dimensional reduction, finding that one of the two diagrams vanishes, and discuss the procedure for calculating the one-point function of a generic operator from the SU(2) subsector. Finally, we explicitly evaluate the one-loop correction to the one point function of the BPS vacuum state, finding perfect agreement with an earlier string theory prediction. This constitutes a highly non-trivial test of the gauge-gravity duality in a situation where both supersymmetry and conformal symmetry are partially broken.

• 出版日期2017-1-23