Abstract :
A dynamical model for the dark energy is presented in which the “quintessence” field is the axion, image, of a spontaneously broken global image symmetry whose potential is induced by the instantons of a new gauge group image. The image coupling becomes large at a scale image starting from an initial value M at high energy which is of the order of the Standard Model (SM) couplings at the same scale M. A perspective on a possible unification of image with the SM will be briefly discussed. We present a scenario in which image is trapped in a false vacuum characterized by an energy density image. The lifetime of this false vacuum is estimated to be extremely large. Other estimates relevant to the “coincidence issue” include the ages of the universe when the image potential became effective, when the acceleration “began” and when the energy density of the false vacuum became comparable to that of (baryonic and non-baryonic) matter. Other cosmological consequences include a possible candidate for the weakly interacting (WIMP) Cold Dark Matter as well as a scenario for leptogenesis. A brief discussion on possible laboratory detections of some of the particles contained in the model will also be presented.
