Shadow multiplets and superHiggs mechanism

TL;DR

This paper explores a shadow relation in Freund Rubin compactifications, revealing a pairing of different fields that suggests a superHiggs mechanism and the possibility of consistent massive truncations in supergravity theories.

Contribution

It introduces the concept of shadow relations between fields in compactifications and proposes a new interpretation of the reduced theory as a spontaneously broken phase of a higher supersymmetric theory.

Findings

Shadow relations link different spin and mass fields in compactifications.

Massive truncation of 11D supergravity may be consistent with shadow partners.

Evidence of superHiggs phenomena in ${ m N}=2$ and ${ m N}=3$ cases.

Abstract

We discuss a general feature of Freund Rubin compactifications that was previously overlooked. It consist in a curious pairing, which we call a shadow relation, of completely different (in terms of spin and mass) fields of the dimensionally reduced theory. Particularly interesting is the case where the compactification preserves a certain amount of supersymmetry, giving rise to a shadowing phenomenon between whole supermultiplets of fields. In particular, there are strong suggestions about the consistency of a massive truncation of 11D supergravity to the massless modes of the graviton supermultiplet plus the massive modes of its shadow partner. This fact has important consequences in the ${\cal N}=2$ and ${\cal N}=3$ cases, which seem to realize respectively a Higgs or a superHiggs phenomenon. In other words, we are led to reinterpret the dimensionally reduced theory as a spontaneously broken phase of some higher (super)symmetric theory.