Can One have Significant Deviations from Leptonic $3\times 3$ Unitarity in the Framework of Type I Seesaw Mechanism?

Nuno Rosa Agostinho, G. C. Branco, Pedro M. F. Pereira +2

We address the question of deviations from $3\times 3$ unitarity of the leptonic mixing matrix showing that, contrary to conventional wisdom, one may have significant deviations fr…