Inconsistencies of massive charged gravitating higher spins

https://lecospa.ntu.edu.tw/wp-content/uploads/2014/08/pub_2013_16.pdf

Massive gravity acausality redux

Tractors, mass, and Weyl invariance

A contribution to the collection of reviews "Introduction to Higher Spin Theory" edited by S. Fredenhagen, this introductory article is a pedagogical account of higher-spin fields and their connections with String Theory. We start with the motivations for and a brief historical overview of the subject. We discuss the Wigner classifications of unitary irreducible Poincar\'e-modules, write down covariant field equations for totally symmetric massive and massless representations in flat space, and consider their Lagrangian formulation. After an elementary exposition of the AdS unitary representations, we review the key no-go and yes-go results concerning higher-spin interactions, e.g., the Velo-Zwanziger acausality and its string-theoretic resolution among others. The unfolded formalism, which underlies Vasiliev's equations, is then introduced to reformulate the flat-space Bargmann-Wigner equations and the AdS massive-scalar Klein-Gordon equation, and to state the "central on-mass-shell theorem". These techniques are used for deriving the unfolded form of the boundary-to-bulk propagator in $AdS_4$, which in turn discloses the asymptotic symmetries of (supersymmetric) higher-spin theories. The implications for string-higher-spin dualities revealed by this analysis are then elaborated.

From Higher Spins to Strings: A Primer

A model independent ultraviolet cutoff for theories with charged massive higher spin fields

The minimally coupled spin-2 wave equation is shown to lead to noncausal propagation even if the correct number of constraints are obtained.

Minimal electromagnetic coupling for massive spin-two fields

It is shown that cosmological structures can be used to make tachyonic theories that do not contain logical paradoxes. A general-relativistic Proca equation is then analyzed as an example of a field-theoretic model that can have this type of tachyonic behavior. It is found that only one form of this equation never gives tachyon-type behavior.

A. Shamaly

Papers

Minimal electromagnetic coupling for massive spin-two fields

Tachyon behavior in general relativity