The role of the 1.5 order formalism and the gauging of spacetime groups in the development of gravity and supergravity theories

TL;DR

This paper reviews the 1.5 formalism and gauging of spacetime groups, highlighting their crucial roles in developing supergravity theories and ensuring their local supersymmetry invariance.

Contribution

It provides a comprehensive review of the 1.5 formalism, gauging of super Poincare group, and auxiliary fields in supergravity, emphasizing their historical and theoretical significance.

Findings

The 1.5 formalism was essential in discovering supergravity.

Gauging the super Poincare group led to the formulation of supergravity.

Auxiliary fields enable the most general coupling of supergravity to matter.

Abstract

The 1.5 formalism played a key role in the discovery of supergravity and it has been used to prove the invariance of essentially all supergravity theories under local supersymmetry. It emerged from the gauging of the super Poincare group to find supergravity. We review both of these developments as well as the auxiliary fields for simple supergravity and its most general coupling to matter using the tensor calculus.