On D=5 super Yang-Mills theory and (2,0) theory

TL;DR

This paper explores the potential of five-dimensional maximally supersymmetric Yang-Mills theory to fully capture the six-dimensional (2,0) theory, suggesting deep connections and implications for finiteness and dualities.

Contribution

It proposes that D=5 MSYM may encode all degrees of freedom of the (2,0) theory, offering new insights into its nonperturbative structure and finiteness properties.

Findings

Arguments suggest D=5 MSYM contains all (2,0) theory degrees of freedom.

Potential implications for all-order finiteness of D=5 MSYM.

S-duality may impose nonperturbative constraints.

Abstract

We discuss how D=5 maximally supersymmetric Yang-Mills theory (MSYM) might be used to study or even to define the (2,0) theory in six dimensions. It is known that the compactification of (2,0) theory on a circle leads to D=5 MSYM. A variety of arguments suggest that the relation can be reversed, and that all of the degrees of freedom of (2,0) theory are already present in D=5 MSYM. If so, this relation should have consequences for D=5 SYM perturbation theory. We explore whether it might imply all orders finiteness, or else an unusual relation between the cutoff and the gauge coupling. S-duality of the reduction to D=4 may provide nonperturbative constraints or tests of these options.