Fermion Doubling and Berenstein--Maldacena--Nastase Correspondence

TL;DR

The paper investigates fermion doubling in string bit models related to the BMN correspondence, revealing supersymmetry violations at large N and suggesting similar issues in super-Yang--Mills theory.

Contribution

It identifies fermion doubling in string bit models and discusses its implications for supersymmetry and the BMN correspondence.

Findings

Fermion doubling occurs in the string bit model.

Doubling causes supersymmetry violation at large N.

Doubling likely affects super-Yang--Mills theory through BMN operators.

Abstract

We show that the string bit model suffers from doubling in the fermionic sector. The doubling leads to strong violation of supersymmetry in the limit $N\to\infty$. Since there is an exact correspondence between string bits and the algebra of BMN operators even at finite $N$, doubling is expected also on the side of super-Yang--Mills theory. We discuss the origin of the doubling in the BMN sector.