"Massive" Higher Spin Multiplets and Holography

TL;DR

The work studies the higher-spin symmetry enhancement point in the AdS5xS5 holographic setup and its correspondence with the spectrum of single-trace operators in large-N N=4 SYM. It combines extrapolated string spectra, HS symmetry via hs(2,2|4), and Polya counting to classify massless and massive HS multiplets, including doubletons and KK excitations, and to identify the Semishort versus long multiplets arising under interactions. A key result is the exact-like agreement between the HS-extrapolated bulk spectrum and the free boundary spectrum, along with a calculable one-loop anomalous-dimension pattern for HS currents and insights into integrability and Higgs-like mixing (La Grande Bouffe) at nonzero coupling. The findings bolster HS holography and point to future directions in worldsheet descriptions and finite-N HS dynamics.

Abstract

We review the extrapolation of the single-particle string spectrum on AdS(5)xS(5) to the Higher Spin enhancement point and the successful comparison of the resulting spectrum with the one of single-trace gauge-invariant operators in N=4 supersymmetric Yang-Mills theory. We also describe how to decompose the common spectrum in terms of massless and massive representations of the relevant Higher Spin symmetry group. Based on the lecture delivered by M. Bianchi at the First Solvay Conference on Higher-Spin Gauge Theories held in Bruxelles, on May 12-14, 2004.