Elko in 1+1 dimensions

Abstract

The quantum field operator for spin-half Elko describes a massive self-interacting fermionic dark matter candidate of mass dimension one. It has been shown that the theory has a built-in violation of the Lorentz symmetry and a well-defined element of non-locality in the form of a preferred direction. This note shows that quantum field operators constructed using spin-half and higher-spin Elko violate Lorentz symmetry from first principle. Subsequently, we study the kinematics of Elko and its quantum field operator for any spin along the preferred direction.