The Cabibbo angle as a universal seed for quark and lepton mixings

Abstract

A model-independent ansatz to describe lepton and quark mixing in a unified way is suggested based upon the Cabibbo angle. In our framework neutrinos mix in a "Bi-Large" fashion, while the charged leptons mix as the "down-type" quarks do. In addition to the standard Wolfenstein parameters (λ, A) two other free parameters (ψ, δ) are needed to specify the physical lepton mixing matrix. Through this simple assumption one makes specific predictions for the atmospheric angle as well as leptonic CP violation in good agreement with current observations.

Status and prospects of ‘bi-large’ leptonic mixing

“…Apart from fitting observation, another reason for these ansatze is that they fit well within the framework of unified theories [15]. In addition, they open the door to the possibility of having the Cabibbo angle as a universal seed for quark as well as lepton mixings [16]. Here we give an overview of the predictions of bi-large mixing patterns for the lepton mixing matrix.…”

“…Here we give an overview of the predictions of bi-large mixing patterns for the lepton mixing matrix. For definiteness we focus on pattern T1, T2 from the recent paper in [17], while T3 and T4 are taken from a previous paper [16]. Following Ref.…”

Modulated bimaximal neutrino mixing

“…The above design is motivated in the Bi-large mixing frameworks [37,40,41] and it finds some resemblance with Tri-Bimaximal Cabibbo mixing matrix [51]. Unlike the original BM mixing scheme (Scheme-I), the present one permits the entry of Dirac-CP violating phase within the neutrino sector.…”

“…In the present parametrization as θ ν 13 = 0, this feature is more prominent and seems logical in contrast to those model independent possibilities discussed in refs. [41,50].…”

“…This indicates either to preclude the BM framework or to harmonize the underlying motivation a little. One such improved follow-up of the BM mechanism is the Bi-Large scenario [37][38][39][40][41]which assumes the solar and the atmospheric angles as equal, non-maximal, and large in general, but leaves a scope to embrace a partial Bi-maximal scenario. Also, in this framework the reactor angle is assumed as large as the Cabibbo angle.…”