Do the Small Numbers in the Quark Mixing arise from New Physics?

Abstract

We put forward the conjecture that the small numbers in the $V_{\text{CKM}}$ matrix, are generated by physics beyond the Standard Model. We identify as small numbers $V_{ub}$ and the strength of CP violation, measured by $|\text{Im}Q|$, where $Q$ stands for a rephasing invariant quartet of $V_{\text{CKM}}$. We illustrate how the conjecture can be realised in the context of an extension of the Standard Model where an up-type vector-like quark is introduced leading to a realistic spectrum of quark masses and an effective $V_{\text{CKM}}$ in agreement with experiment.

Comments: 15 pages, 1 table