Exact deconstruction of the 6D (2,0) theory

Abstract

The dimensional-deconstruction prescription of Arkani-Hamed, Cohen, Kaplan, Karch and Motl provides a mechanism for recovering the A-type (2,0) theories on T2, starting from a four-dimensional 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 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 S4 to the (2,0) partition function on S4× T2. In both cases we find exact agreement. The partition function calculation sets up a dictionary between exact results in 4D and 6D.