(Iso)spin from Isospin in Top-Down Holography

Abstract

Motivated by the spin from isospin mechanism of Jackiw-Rebbi-Hasenfratz-'t Hooft, we study two SU(2) gauged supergravity solutions of the form $M_{d}\times\text{S}^{2}$ containing non-Abelian hedgehog monopole on the 2-sphere. Due to the presence of the monopole, the SO(3) isometry group of the 2-sphere is not a symmetry of the configuration. Instead, a diagonal combination of the SU(2) gauge and the SO(3) isometry of the 2-sphere is the true symmetry of the configuration. Uplifting the solutions to Type II, the gauge-isometry diagonal symmetry becomes a diagonal combination between the SO(3) symmetry of the 2-sphere and a SU(2) symmetry of a 3-sphere used to uplift the configuration. One of the uplifts is supersymmetric and corresponds to the I-brane theory on a 2-sphere. The second background is a deformation of $\text{AdS}_{5}\times\text{S}^{5}$ and is not supersymmetric. We study dilaton fluctuations on the later geometry. Due to the diagonal symmetry, the fluctuations show angular momentum mixing between the SU(2) and SO(3) spins, mimicking the spin from isospin mechanism.