String Theory, Supersymmetry, Unification, and All That

TL;DR

This paper explores the theoretical frameworks of string theory and supersymmetry, highlighting their potential for unification of forces, recent non-perturbative developments, and implications for quantum field theories and fundamental physics.

Contribution

It provides an overview of supersymmetry and string theory, emphasizing recent advances in non-perturbative dualities and the role of branes in unification.

Findings

Supersymmetry enables exact solutions in quantum field theories.

String dualities unify all superstring theories.

Extended objects called branes are central to non-perturbative string theory.

Abstract

String theory and supersymmetry are theoretical ideas that go beyond the standard model of particle physics and show promise for unifying all forces. After a brief introduction to supersymmetry, we discuss the prospects for its experimental discovery in the near future. We then show how the magic of supersymmetry allows us to solve certain quantum field theories exactly, thus leading to new insights about field theory dynamics related to electric-magnetic duality. The discussion of superstring theory starts with its perturbation expansion, which exhibits new features including ``stringy geometry.'' We then turn to more recent non-perturbative developments. Using new dualities, all known superstring theories are unified, and their strong coupling behavior is clarified. A central ingredient is the existence of extended objects called branes.