Global Coherence, Localization, and the Origin of an Effective Cosmological Constant with the TE Framework

The cosmological constant is conventionally introduced in relativistic cosmology as a fundamental parameter inferred empirically from large-scale observations. While phenomenologically successful, its physical interpretation remains unsettled: estimates of vacuum energy density from quantum field theory exceed the observed value by many orders of magnitude. This paper explores whether a cosmological-constant-like contribution can arise as a structural bookkeeping term associated with global spacetime coherence, rather than as a fundamental vacuum energy. The argument begins from an established structural result: when matter actions are restricted to finite spacetime domains via a smooth window function ◇(x), the contracted Bianchi identity requires a compensating stress-energy contribution at the localization boundary. For processes distributed across a causally coherent spacetime, this boundary requirement persists globally and must be carried by a term that is homogeneous, isotropic, and independent of local matter distributions — properties that identify it with a cosmological-constant-like contribution with equation of state w = −1. Dimensional analysis then fixes the scaling ρ_Λ ∼ H²/G. Two worked examples develop this quantitatively. The first provides a first-principles estimate of μ, the mean localization rate per Hubble four-volume per Hubble time, by identifying two independent contributions: a geometric term from Hubble-crossing mode statistics, μ_geo = 2/(3π) ≈ 0.21, and a vacuum term μ_vac ≈ 1 from the uncertainty-principle minimum energy quantum E_min ∼ ℏH. Their sum μ ≈ 1.21, substituted into the Poisson estimate Ω_Λ = 1 − e^(−μ), gives Ω_Λ ≈ 0.70, consistent with the Planck 2018 value of 0.685 to within the uncertainty of the estimate. The observational inversion μ_obs = −ln Ω_m ≈ 1.155 is independently derived and shown to be consistent with the structural estimate. The second example demonstrates that holographic coherence closure of the Hubble horizon gives Ω_m + Ω_Λ = 1, reproducing the Padmanabhan equipartition relation through a different physical motivation. A Friedmann self-consistency check confirms that the ρ_Λ ∝ H² scaling imposes no constraint beyond spatial flatness. An appendix derives E_min ∼ ℏH from the uncertainty principle and establishes the physical meaning of the microscopic-to-macroscopic density ratio as an inverse Bekenstein-Hawking entropy.