Quantum Gravity from the Early Universe: Imprints on the CKM Triangle and BSM Signatures

The influence of a permanent imprint of the aggregated body of real gravitons formed in the early universe on the Cabibbo--Kobayashi--Maskawa (CKM) unitarity triangle is discussed. After incorporating this correction, the apex of the CKM triangle---a tree-level quantity---remains invariant. However, the uncertainty band of $\Delta m_d$, a loop-level quantity, shifts upward, introducing the possibility that the apex lies outside the constraint band once the correction is applied. If confirmed, this would imply an inconsistency within the Standard Model, pointing to the presence of new physics.