# Appearence of higher spin algebra

I start from massles & free scalar field theory in $$d$$-dimenisonal space. It is clear that this theory has conformal symmetry. My question is devoted to derivation of conserved current $$J_{\mu_1\mu_2...\mu_s}=\sum_{k=0}^{s}c_{sk}\partial_{\left\lbrace\mu_1...\mu_k\right.}\phi\partial_{\left.\mu_{k+1}...\mu_s\right\rbrace}\phi,\quad s=2,4,...$$ In this expression braces mean traceless symmetrization. I do not understand from which epxression should I start to derive this current.

• Are you following a reference? – Qmechanic Oct 12 '19 at 14:23
• What do you mean? – Artem Alexandrov Oct 12 '19 at 15:26