Black hole cohomologies in N=4 SYM

Abstract

We systematically investigate BPS cohomologies of $\mathcal{N}=4$ super-Yang-Mills (SYM) theory with gauge group SU$(N)$ with $N=2, 3, 4$, focusing primarily on the BMN sector. We find non-Coulomb graviton cohomologies for $N>2$. For $N>2$, the lightest black hole cohomology in the BMN sector always carries non-trivial $R$-charge and corresponds to the brane-fused type. Therefore, the `core' black holes without hair are `heavier'. We also find that a family of brane-fused cohomologies in $N=3$ is not lifted at the first quantum order. At a fixed charge sector, gravitons carry definite parity under charge conjugation. Up to the levels we have tested, every black hole cohomology either has opposite parity to that of gravitons or is lifted by quantum corrections. We conjecture that black hole cohomologies always carry parity opposite to gravitons in the same charge sector.