A New N=4 Membrane Action via Orbifold

TL;DR

This paper introduces a novel N=4 superconformal field theory in three dimensions, derived as a Z_2-orbifold of a known theory, with implications for M2-branes and dualities in string theory.

Contribution

It presents a new Lagrangian for N=4 superconformal field theory on M2-branes, obtained via a Z_2-orbifold, and analyzes its moduli space and duality properties.

Findings

Moduli space has three branches consistent with D2-brane physics

The theory exhibits a manifest Z_2-symmetry exchanging two R^4/Z_2's

Suggests a new non-perturbative duality involving O2^{-}-branes

Abstract

We propose a new Lagrangian describing N=4 superconformal field theory in three dimensions. This theory is believed to describe interacting field theory on the worldvolume of a M2-brane on an orbifold, and is obtained as a Z_2-quotient of the theory proposed by Bagger and Lambert. Despite unusual Chan-Paton structures, we can take Z_2-orbifold by using SU(2)\times SU(2) bifundamental representations. We also analyze the moduli space of this theory and found three branches. With an assumption of a broken U(1) symmetry, the moduli space is consistent with that of the D2-brane in the strong coupling limit of Type IIA string theory if the gauge group is O(4). Our action has manifest Z_2-symmetry exchanging two R^4/Z_2's in M-theory, and this suggests a new non-perturbative duality between a O2^{-}-brane on orbifold R^4/Z_2 and a O2^{-}-brane with D6-branes.