Dark matter and dark gauge fields

Following the unexpected theoretical discovery of a mass dimension one fermionic quantum field of spin one half, we now present first results on two _local_ versions. The Dirac and Majorana fields of the standard model of particle physics are supplemented by their natural counterparts in the dark matter sector. The possibility that a mass dimension transmuting symmetry may underlie a new standard model of particle physics is briefly suggested.Comment: This manuscript combines a plenary talk (by DVA) and an invited talk (by DS) at "Dark 2007 - Sixth International Heidelberg Conference on Dark Matter in Astro and Particle Physics (Sydney, Australia, 24th-28th September 2007)." 11 pages. v2: minor typos correcte

Self-interacting Elko dark matter with an axis of locality

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.Comment: 14 pages (RevTex

Superluminal group velocity through near-maximal neutrino oscillations

Recently it was suggested that the observation of superluminal neutrinos by the OPERA collaboration may be due to group velocity effects resulting from close-to-maximal oscillation between neutrino mass eigenstates, in analogy to known effects in optics. We show that superluminal propagation does occur through this effect for a series of very narrow energy ranges, but this phenomenum cannot explain the OPERA measurement.Comment: Reworking includes corrections due to finite width of the wave packet, further references, and comments on other corrections, causality, the new OPERA results, and why the size of neutrino wave packet provides important constraint