Vacua of M-theory and N=2 strings

TL;DR

This paper explores various vacua of an M-theory unifying string and membrane dynamics in 2+2 dimensions, revealing how different string theories and M-branes emerge as specific vacua with consistent gauge and effective dynamics.

Contribution

It demonstrates that all known string and membrane theories can be realized as vacua of a unified N=(2,1) string framework, including novel connections to M-theory and gauge symmetries.

Findings

All string and membrane theories are realized as vacua of the N=(2,1) string.

Open membranes exhibit Chan-Paton fields, linking to gauge symmetries.

M-brane fluctuations match Born-Infeld dynamics with electromagnetic fields.

Abstract

String and membrane dynamics may be unified into a theory of 2+2 dimensional self-dual world-volumes living in a 10+2 dimensional target space. Some of the vacua of this M-theory are described by the N=(2,1) heterotic string, whose target space theory describes the world-volume dynamics of 2+2 dimensional `M-branes'. All classes of string and membrane theories are realized as particular vacua of the N=(2,1) string: Type IIA/B strings and supermembranes arise in the standard moduli space of toroidal compactifications, while type ${\rm I}'$ and heterotic strings arise from a $\bf Z_2$ orbifold of the N=2 algebra. Yet another vacuum describes M-theory on a ${\bf T}^5/{\bf Z}_2$ orientifold, the type I string on $ {\bf T}^4$, and the six-dimensional self-dual string. We find that open membranes carry `Chan-Paton fields' on their boundaries, providing a common origin for gauge symmetries in M-theory. The world-volume interactions of M-brane fluctuations agree with those of Born-Infeld effective dynamics of the Dirichlet two-brane in the presence of a non-vanishing electromagnetic field on the brane.