Higher spin algebras as higher symmetries
arXiv:0704.0898
Abstract
The exhaustive study of the rigid symmetries of arbitrary free field theories is motivated, along several lines, as a preliminary step in the completion of the higher-spin interaction problem in full generality. Some results for the simplest example (a scalar field) are reviewed and commented along these lines.
14 pages, expanded version of the lectures presented at the ``5th international school and workshop on QFT & Hamiltonian systems'' (Calimanesti, May 2006); v2: minor corrections performed, comments added and refs updated