Informational Causal-Diamond Completion (ICDC)

Informational Causal Diamond Completion (ICDC) presents a background independent, non perturbative quantum gravity framework built from finite causal diamonds and their boundary Hilbert spaces. Geometry is encoded on causal diamond waists using SU(2) spin network labels, and dynamics are given by a discrete state sum on finite two complexes whose vertex phases reproduce the Regge action in the large spin limit. A central interpretive step is treating the ADM lapse as a physically meaningful local update rate, so horizons correspond to vanishing update rate while preserving diffeomorphism invariance. Within this setting, boundary unitarity and KMS reality uniquely fix the Barbero Immirzi parameter to γ = 1. This removes a free coupling and yields a minimal nonzero area eigenvalue Amin = 4π√3 G and an associated fundamental length scale ℓ* = 3^(1/4) ℓP. Using stationary phase methods together with standard Γ convergence results under shape regular refinement, the model recovers the Einstein Hilbert action in the continuum limit, propagates exactly two graviton polarizations, and reproduces weak field, post Newtonian, and gravitomagnetic limits. Standard Model gauge structure and anomaly cancellation are preserved on the emergent geometry through a Ginsparg Wilson type discrete Dirac operator and topological index arguments. Because ℓ* is fixed, the framework makes parameter free, falsifiable predictions. These include a discrete area spectrum whose asymptotic step approaches 8πG, a universal lower bound on gravitational wave ringdown echo delays ∆techo ≥ 2 r* ln(r*/ℓ*) with r* = 3√3 M, and short distance gravitational softening with static potential V(r) proportional to (1 − e^(−r/ℓ*))/r, implying a monotonic crossover from flat to Newtonian scaling. Classical singularities are replaced by finite thickness update saturated layers that mediate bounces rather than divergences, leading to a nonsingular Big Bounce cosmology. The observed cosmological constant is interpreted as a large scale tiling noise of discrete causal diamond geometry at the Hubble scale, not vacuum energy. The paper outlines near term observational tests via gravitational wave echo searches, precision short range gravity experiments, and large scale structure surveys, and discusses a future coarse graining program to fully resolve infrared cosmology and dark matter phenomenology.