Elko Field Theory and the Nature of Elko Darkness

We show that the Elko Lagrangian dark matter candidate is gauge-invariant under local gauge transformations and that non-abelian gauge invariance can be set up quite naturally. This leads naturally to Elko symmetry currents. These Elko symmetry currents can then be coupled with the symmetry currents of the Electroweak theory to form interaction Hamiltonian densities, thus providing a natural mechanism for Elko particles to interact directly with Standard Model matter in addition to the Higgs particle. This could have profound implications for the detection of Elko at the LHC. We also show that in a certain sense Elko fields are non-local even along the axis of locality. This may make direct detection of Elko difficult. We propose that Elko would therefore still seem dark to us, as far as direct detection efforts are concerned. We propose however, that the allowed gauge interactions between Elko and the electroweak sector of the Standard Model may result in the possibility of new experiments to be devised to look for Elko indirectly via studying the Standard Model particles that are involved in an Elko interaction. Such new experiments could complement existing ideas of developing experiments to detect the Elko particles based on their interaction with the Higgs particle.