Li, MZ (reprint author), Chinese Acad Sci, Inst High Energy Phys, POB 918-4, Beijing 100039, Peoples R China.
k-Essence is a possible candidate for dark energy of the Universe. In this Letter we consider couplings of k-essence to the matter fields of the standard electroweak theory and study the effects of the cosmological CPT violation induced by the CPT violating ether during the evolution of the k-essence scalar field on the laboratory experiments and baryogenesis. Our results show that the matter and antimatter asymmetry can be naturally explained via leptogenesis without conflicting with the experimental limits on CPT violation test. The mechanism for baryogenesis proposed in this Letter provides a unified picture for dark energy and baryon matter of our Universe and allows an almost degenerate neutrino mass pattern with a predicted rate on the neutrinoless double beta decays accessible to the experimental sensitivity in the near future. (C) 2003 Elsevier B.V. All rights reserved.