Continuous symmetry defects and brane/anti-brane systems

A bstract We explicitly compute correlation functions with the insertion of a continuous symmetry defect in bosonic field theories. To recover its expected action on the charged operators, the definition of the defect must be modified to include a specific contact term. This can be regarded as a singular background gauge field for the global symmetry. It can be traced to the definition of the generating functional for current correlators, where the source is akin to a background gauge field for the symmetry. For holographic theories, it has been proposed that continuous symmetry defects are realized in terms of non-BPS D ( q – 1) branes. We argue that these can be regarded as $$ Dq/\overline{Dq} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Dq</mml:mi> <mml:mo>/</mml:mo> <mml:mover> <mml:mi>Dq</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> system and show its application to the case of the baryonic symmetry in the Klebanov-Witten theory. The $$ Dq/\overline{Dq} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Dq</mml:mi> <mml:mo>/</mml:mo> <mml:mover> <mml:mi>Dq</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> can be regarded as a particular regularization of the defect, holographically realizing the field theory discussion.