Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
1998-11-21
Nucl.Phys. B557 (1999) 25
Physics
High Energy Physics
High Energy Physics - Phenomenology
36 pages, LaTeX, 6 figures. Substantially enlarged; previous mechanisms strengthened and generalized; many new results added
Scientific paper
10.1016/S0550-3213(99)00377-6
Recent theoretical developments have shown that extra spacetime dimensions can lower the fundamental GUT, Planck, and string scales. However, recent evidence for neutrino oscillations suggests the existence of light non-zero neutrino masses, which in turn suggests the need for a heavy mass scale via the seesaw mechanism. In this paper, we make several observations in this regard. First, we point out that allowing the right-handed neutrino to experience extra spacetime dimensions naturally permits the left-handed neutrino mass to be power-law suppressed relative to the masses of the other fermions. This occurs due to the power-law running of the neutrino Yukawa couplings, and therefore does not require a heavy scale for the right-handed neutrino. Second, we show that a higher-dimensional analogue of the seesaw mechanism may also be capable of generating naturally light neutrino masses without the introduction of a heavy mass scale. Third, we show that such a higher-dimensional seesaw mechanism may even be able to explain neutrino oscillations without neutrino masses, with oscillations induced indirectly via the masses of the Kaluza-Klein states. Fourth, we point out that even when higher-dimensional right-handed neutrinos are given a bare Majorana mass, the higher-dimensional seesaw mechanism surprisingly replaces this mass scale with the radius scale of the extra dimensions. Finally, we also discuss a possible new mechanism for inducing lepton-number violation by shifting the positions of D-branes in Type I string theory.
Dienes Keith R.
Dudas Emilian
Gherghetta Tony
No associations
LandOfFree
Light Neutrinos without Heavy Mass Scales: A Higher-Dimensional Seesaw Mechanism does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Light Neutrinos without Heavy Mass Scales: A Higher-Dimensional Seesaw Mechanism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Light Neutrinos without Heavy Mass Scales: A Higher-Dimensional Seesaw Mechanism will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-282857