The Standard Model as an Open-System Effective Theory: Latency Portals, Running Dissipation, and Precision-Spectroscopy Kill-Tests (MetaTime v40.3: Derived Line-Shape Constraints and Portal-RG Consistency)

We formulate a minimal open-system completion of the MetaTime program in which the observed
Standard Model (SM) dynamics arises as a reduced boundary description interacting with unobserved
bulk degrees of freedom. The extension is encoded by a causal non-Markovian influence functional
on the Schwinger–Keldysh closed-time path. The central control parameter is a dimensionless
latency/impedance amplitude ΓL(µ) that measures dissipative strength relative to a characteristic
boundary scale µ. In contrast to earlier drafts, we (i) enforce portal–renormalization consistency
by adopting a minimal safe irrelevant SM-singlet latency portal of scaling dimension ∆ = 6 and
deriving the corresponding running exponent η ≃ 2(∆ − 4) = 4, while showing how electroweak
symmetry breaking produces an effective trace-coupling in the infrared; and (ii) derive an explicit
precision-spectroscopy constraint from the Markov/Lindblad limit of the influence functional: the
latency-induced homogeneous linewidth for an atomic transition n↔m obeys ∆νnm ≃
γ
2π
(∆Lnm)
2
with γ = ΓL(µ)µ, where ∆Lnm is a portal matrix-element difference. Applying this to hydrogen
1S–2S yields a falsifiable bound on ΓL(µH) given a matching scale ΛL. Finally, we connect the proton-
persistence barrier Seff (MetaTime “Anchor” conjecture) to a conservative microscopic envelope for
ΓL via a coarse-grained multi-channel model with explicit Neff dependence, and identify muonic and
highly charged hydrogen-like systems as amplification targets.