We revisit the N=6 superconformal Chern-Simons-matter theories and their supergravity duals in the context of generalized symmetries. This allows us to finally clarify how the $SU(N)times SU(N)$ and $(SU(N)times SU(N))/mathbb{Z}_N$ theories, as well as other quotient theories that have recently been discussed, fit into the holographic framework. It also resolves a long standing puzzle regarding the di-baryon operator in the $U(N)times U(N)$ theory.
We study reductions of 6d theories on a $d$-dimensional manifold $M_d$, focusing on the interplay between symmetries, anomalies, and dynamics of the resulting $(6-d)$-dimensional theory $T[M_d]$. We refine and generalize the notion of polarization to polarization on $M_d$, which serves to fix the spectrum of local and extended operators in $T[M_d]$. Another important feature of theories $T[M_d]$ is that they often possess higher-group symmetries, such as 2-group and 3-group symmetries. We study the origin of such symmetries as well as physical implications including symmetry breaking and symmetry enhancement in the renormalization group flow. To better probe the IR physics, we also investigate the t Hooft anomaly of 5d Chern-Simons matter theories. The present paper focuses on developing the general framework as well as the special case of $d=0$ and 1, while an upcoming paper will discuss the case of $d=2$, $3$ and $4$.
We analyse the symmetries of a class of A-type little string theories that are engineered by $N$ parallel M5-branes with M2-branes stretched between them. This paper deals with the so-called reduced free energy, which only receives contributions from the subset of the BPS states that carry the same charges under all the Cartan generators of the underlying gauge algebra. We argue (and check explicitly in a number of examples) that the former is invariant under the paramodular group $Sigma_Nsubset Sp(4,mathbb{Q})$, which gets extended to a subgroup of $Sp(4,mathbb{R})$ in the Nekrasov-Shatashvili-limit. This extension agrees with the observation made in arXiv:1706.04425 that these BPS states form a symmetric orbifold CFT. Furthermore, we argue that $Sigma_N$ (along with other symmetries) places strong constraints on the BPS counting function that governs the intersection between the M5- and M2-branes.
We study confinement in 4d $mathcal{N}=1$ $SU(N)$ Super-Yang Mills (SYM) from a holographic point of view, focusing on the 1-form symmetry and its relation to chiral symmetry breaking. In the 5d supergravity dual, obtained by truncation of the Klebanov-Strassler solution, we identify the topological couplings that determine the 1-form symmetry and its t Hooft anomalies. One such coupling is a mixed 0-form/1-form symmetry anomaly closely related to chiral symmetry breaking in gapped confining vacua. From the dual gravity description we also identify the infra-red (IR) 4d topological field theory (TQFT), which realises chiral symmetry breaking and matches the mixed anomaly. Finally, complementing this, we derive the chiral and mixed anomalies from the Little String Theory realization of pure SYM.
We study the recently proposed AdS$_7$/CFT$_6$ dualities for a class of 6d $mathcal{N} = (1,0)$ theories that flow on the tensor branch to long linear quiver gauge theories. We find a precise agreement in the symmetries and in the spectrum of charged states between the 6d SCFTs and their conjectured AdS$_7$ duals. We also confirm a recent conjecture that a discrete $S_N$ symmetry relating the baryons in the quiver theories is in fact gauged.
The aim of these Lectures is to provide a brief overview of the subject of asymptotic symmetries of gauge and gravity theories in asymptotically flat spacetimes as background material for celestial holography.