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Alternatives to the Seesaw: Extra Z's and Constraints on Large Extra Dimensions

Paul Langacker
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Abstract

Alternatives to the traditional grand unified theory seesaw for neutrino masses are briefly described. These include the possibility of large extra dimensions and various possibilities for models involving an extra U(1)' gauge symmetry. The difficulty of observing Majorana phases in neutrinoless double beta decay is also briefly commented on.

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Paul Langacker. 2003-04-10. Alternatives to the Seesaw: Extra Z's and Constraints on Large Extra Dimensions. https://doi.org/10.1142/s0217751x03017336

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