Exact Deconstruction of the 6D (2,0) Theory

Understand

The dimensional-deconstruction prescription of Arkani-Hamed, Cohen, Kaplan, Karch and Motl provides a mechanism for recovering the $A$-type (2,0) theories on $T^2$, starting from a four-dimensional $\mathcal N=2$ circular-quiver theory.

• We put this conjecture to the test using two exact-counting arguments: In the decompactification limit, we compare the Higgs-branch Hilbert series of the 4D $\mathcal N=2$ quiver to the "half-BPS" limit of the (2,0) superconformal index.
• We also compare the full partition function for the 4D quiver on $S^4$ to the (2,0) partition function on $S^4 \times T^2$.
• In both cases we find exact agreement.