The N=2(4) string is self-dual N=4 Yang-Mills

TL;DR

This paper shows that N=2 string amplitudes, under Lorentz covariance constraints, describe a self-dual N=4 super Yang-Mills theory in 2+2 dimensions, characterized by topological features and no loop corrections.

Contribution

It establishes a connection between N=2 string amplitudes and self-dual N=4 super Yang-Mills theory, highlighting its topological nature and ghost structure.

Findings

N=2 string amplitudes describe self-dual N=4 super Yang-Mills

The theory exhibits topological-like behavior with vanishing loop corrections

Lorentz covariance links N=2 and N=4 string formulations

Abstract

N=2 string amplitudes, when required to have the Lorentz covariance of the equivalent N=4 string, describe a self-dual form of N=4 super Yang-Mills in 2+2 dimensions. Spin-independent couplings and the ghost nature of SO(2,2) spacetime make it a topological-like theory with vanishing loop corrections.