On supergravity in (10,2)

TL;DR

This paper explores the formulation of locally supersymmetric theories in (10,2) signature using F-algebra, analyzing geometric curvatures, gauge transformations, and the implications of quadratic theories and dimensional reduction on spacetime structure.

Contribution

It introduces a framework for constructing supersymmetric theories in (10,2) signature based on F-algebra, and examines their geometric and physical properties, including contraction to lower dimensions.

Findings

Quadratic theories in (10,2) signature relate to Einstein-like equations.

Dimensional reduction is replaced by group contraction, leading to emergent spacetime.

Multi-temporal degrees of freedom connect to ultra-hyperbolic wave equations.

Abstract

We consider the problem of creating locally supersymmetric theories in signature (10,2). The most natural algebraic starting point is the F-algebra, which is the de Sitter-type (10,2) extension of the super-Poincare algebra. We derive the corresponding geometric group curvatures and evaluate the transformations of the associated gauge fields under the action of an infinitesimal group element. We then discuss the formation of locally supersymmetric actions using these quantities. Due to the absence of any vielbein terms there is no obvious way to define spacetime as such. In addition, there is also no way in which we may naturally construct an action which is linear in the twelve dimensional curvatures. We consider the implications of the simplest possible quadratic theories. We then investigate the relationship between the twelve dimensional theories and Lorentz signature theories in lower dimensions. We argue that in this context the process of dimensional reduction must be replaced by that of group theoretic contraction. Upon contraction a regular spacetime emerges and we find that the twelve dimensional curvature constraint reduces to an Einstein-type equation in which a quadratic non-linearity in the Ricci scalar is suppressed by a factor of the same magnitude as the cosmological constant. Finally, we discuss the degrees of freedom of multi-temporal variables and their relation to ultra-hyperbolic wave equations.