The Collapse of Time: When Decoherence Meets Chronon

This article clarifies the relationship between quantum decoherence, measurement outcome selection and the Chronon Field. Its central result is a separation: standard decoherence, objective wave-function collapse and a possible Chronon residual are three distinct concepts. Standard open-system quantum dynamics remain the mandatory baseline. Environmental coupling can suppress observable coherence, but this process does not by itself select a unique measurement outcome. Conversely, the minimal Chronon framework contains no stochastic or nonlinear state-reduction law and therefore does not constitute an objective-collapse theory. The admissible Chronon sector is restricted to gauge-safe post-standard residuals. Using the normalized tempo factor Φ̂ and the residual χΦ=lnΦ̂−U/c², candidate quantum observables are written as differential phase or coherence-loss responses after subtraction of standard Hamiltonian, environmental and instrumental contributions. The article identifies an important experimental degeneracy: a simple gravitational-height scan can constrain only a product between the metrological Chronon slope εΦ and a platform-specific quantum coupling. Independent identification therefore requires an external metrological channel. A joint clock-and-coherence experiment is proposed in which optical-clock residuals define an independent exposure for quantum measurements. Blind crossovers, nuisance controls, uncertainty propagation and fail-fast gates are required before interpretation. Finally, the paper specifies what a genuine Chronon objective-collapse theory would additionally require: a modified state dynamics, probability law, covariance and no-signalling analysis, together with explicit energy bookkeeping. The work remains C0 and reports no quantum detection. Its scientific contribution is to make the boundaries between decoherence, collapse and Chronon residual experimentally explicit.