Aspects of a supersymmetric Brans-Dicke theory

TL;DR

This paper explores a supersymmetric extension of the Brans-Dicke theory, revealing that its gravitational-matter coupling differs significantly from the original, raising questions about its phenomenological viability.

Contribution

It introduces the Minimal Supersymmetric extension of the Brans-Dicke theory and analyzes its unique phenomenological features and potential inconsistencies.

Findings

The MSBD model's gravitational sector does not couple universally to matter.

The phenomenology of the MSBD model differs markedly from the original Brans-Dicke theory.

Potential phenomenological inconsistency due to non-universal matter coupling.

Abstract

We consider a locally supersymmetric theory where the Planck mass is replaced by a dynamical superfield. This model can be thought of as the Minimal Supersymmetric extension of the Brans-Dicke theory (MSBD). The motivation that underlies this analysis is the research of possible connections between Dark Energy models based on Brans-Dicke-like theories and supersymmetric Dark Matter scenarios. We find that the phenomenology associated with the MSBD model is very different compared to the one of the original Brans-Dicke theory: the gravitational sector does not couple to the matter sector in a universal metric way. This feature could make the minimal supersymmetric extension of the BD idea phenomenologically inconsistent.