Self-interacting Elko dark matter with an axis of locality

TL;DR

This paper explores a novel form of dark matter based on Elko spinors, which break Lorentz symmetry subtly by having a hidden preferred direction, yet maintain locality along that axis, offering a new perspective on fermionic dark matter.

Contribution

It introduces a mass dimension one fermionic dark matter model with a preferred axis of locality, extending previous Elko work and revealing subtle Lorentz symmetry breaking.

Findings

Elko fields contain a hidden preferred direction.

Locality is preserved along the preferred axis.

Elko provides a viable fermionic dark matter candidate.

Abstract

This communication is a natural and nontrivial continuation of the 2005 work of Ahluwalia and Grumiller on Elko. Here we report that Elko breaks Lorentz symmetry in a rather subtle and unexpected way by containing a `hidden' preferred direction. Along this preferred direction, a quantum field based on Elko enjoys locality. In the form reported here, Elko offers a mass dimension one fermionic dark matter with a quartic self-interaction and a preferred axis of locality. The locality result crucially depends on a judicious choice of phases.