Mesons in marginally deformed AdS/CFT

Abstract

We study the embedding of spacetime filling D7-branes in β-deformed backgrounds which, according to the AdS/CFT dictionary, corresponds to flavoring β-deformed N = 4 super Yang-Mills. We consider supersymmetric and more general non-supersymmetric three parameter deformations. The equations of motion for quadratic fluctuations of a probe D7-brane wrapped on a deformed three-sphere exhibit a non-trivial coupling between scalar and vector modes induced by the deformation. Nevertheless, we manage to solve them analytically and find that the mesonic mass spectrum is discrete, with a mass gap and a Zeeman-like splitting occurs. Finally we propose the action for the dual field theory as obtained by * -product deformation of super Yang-Mills with fundamental matter.

Mesons from (non) Abelian T-dual backgrounds

“…Similar effects (a change in the mass spectrum proportional to the deformation parameter) happen when studying mesons in field theories dual to TsT deformations [61,62] of a given background.…”

Mesons in gauge/gravity duals

“…For the N = 2 * case, it was shown in [120] that the meson mass obtained from the D7 probe brane fluctuations receives a contribution from the adjoint scalar quark mass, such that there is a mass gap. Recently [122], the embedding of a D7 brane probe into the Lunin-Maldacena background [123] was considered, which is dual to a N = 1 supersymmetric marginal deformation of N = 4 super Yang-Mills theory. Here, a Zeeman-like spitting of the mass spectrum is observed.…”

“…In [150] probe D7 branes were numerically embedded in the nonsupersymmetric Yang-Mills * deformation [71] of the N = 4 theory providing evidence for chiral symmetry breaking. Quarks have also been added to the beta-deformed N = 4 theory in [122] -chiral symmetry breaking is again observed. It appears to be generically true that breaking supersymmetry in gravity duals leads to chiral symmetry breaking.…”

Chiral dynamics and meson with non-commutative dipole field in gauge/gravity dual

“…Thus we find the linear potential relation 8) in which the effective tension τ ef f is a decreasing function of the dipole field strength. At long separation limit L → ∞, i.e.…”

“…The first study of chiral dynamics in [3] used the Constable-Myers geometry [5]. Several scenarios in which supersymmetry breaking leads to chiral symmetry breaking have also been found -for example a set-up of D4 wrapped a circle which describes gauge theory in IR [6], placing the gauge theory on an anti-de-Sitter space [7], on the Lunin-Maldacena background [8,9], or introducing a background magnetic field [10,11]. The meson spectroscopy therein had also been studied (A recent review could be found in [12]) .…”