Why Gravity Predicts Both a Graviton and a Chronoton

General relativity treats space and time on equal footing in the metric tensor. The graviton arises from quantizing the transverse-traceless spatial fluctuations of the linearized metric. Applying an analogous procedure to the temporal component of the metric — within extensions of GR that promote this component to a dynamical variable — produces a massless spin-0 quantum: the chronoton. Brans-Dicke gravity (1961), the canonical and observationally constrained minimal extension of GR, predicts exactly this particle; its scalar field couples to energy density with gravitational strength and satisfies every formal criterion invoked to motivate the graviton: massless, universally coupled, non-renormalizable, and with the same observational status — zero direct detections. We derive the chronoton's propagator, vertex factors, and coupling to the Einstein Equivalence Principle. A recent derivation [5] shows that the EEP coefficient follows from the temporal structure of a Fibonacci conformal field theory, providing a microscopic candidate for the chronoton. We conclude that the choice between standard GR (which constrains the temporal sector) and its minimal extensions (which promote it to a propagating degree of freedom) is the open question at the heart of quantum gravity — and that the asymmetry in research effort — eighty years for the graviton, essentially zero for the chronoton — reflects a bias in physical intuition rather than a difference in theoretical status.