Superstrings, Unifications and dualities

TL;DR

This paper reviews recent progress in string theory and M theory, highlighting their potential to unify gravity with other fundamental forces through duality conjectures and gauge theory correspondences.

Contribution

It discusses how duality conjectures and large N limits of gauge theories may provide a more complete definition of superstring and M theories.

Findings

Advances in understanding physics near the Planck length.

Duality conjectures linking string theories to gauge theories.

Potential for a unified quantum theory of gravity and forces.

Abstract

I describe our understanding of physics near the planck length, in particular the great progress of the last four years in string theory. Superstring theory, and a recent extension called M theory, are leading candidates for a quantum theory that unifies gravity with the other forces. As such, they are certainly not ordinary quantum field theories. However, recent duality conjectures suggest that a more complete definition of these theories can be provided by the large N limits of suitably chosen U(N) gauge theories associated to the asymptotic boundary of spacetime.