This work presents the complete, first-principles resolution of the cosmological constant problem — the 10^122 discrepancy between predicted and observed vacuum energy density that has resisted solution for nearly four decades. The derivation proceeds from three independent, non-adjustable physical pillars: PILLAR 1 — INFORMATIONAL: κ_crit = 10^-78 The causal coherence limit, derived from the Bekenstein bound on the particle horizon. With N_accessible ≈ 10^78 bits, the maximum fraction of retrocausal flux that preserves macroscopic causality is κ_crit = 1/N_accessible. This ensures entropic equilibrium (Ṡ_net = 0) at the Planck scale. PILLAR 2 — GEOMETRIC-DIMENSIONAL: φ/2 = 0.809017 The 8-phase causal array decomposes into two interlocking 4-phase subsystems. Their coherence matrix C†C yields a dominant eigenvalue proportional to the golden ratio φ = (1+√5)/2. Combined with the spectral dimension flow of Loop Quantum Gravity (d_S: 4 → 2), the effective vacuum dimension is d_eff = φ × d_S(UV)/d_S(IR) = φ/2. PILLAR 3 — THERMODYNAMIC: 3/4 = 0.750000 At the half-phase point (180°), forward and retrocausal fluxes are in maximum opposition. The vacuum potential V(φ) ∝ (φ² − η²)² scales quadratically with field displacement. The fraction of energy surviving the half-phase tension is 1 − (1/2)² = 3/4. These combine to give the vacuum exponent: α = φ/2 + 3/4 = 0.809017 + 0.750000 = 1.559017 The vacuum energy density is then: V₀ = E_Planck × κ_crit^α = 2.50 × 10^-122 M_Pl⁴ = 6.90 × 10^-27 J/m³ This matches the observed dark energy density (Planck 2018) with a relative error of 0.29%, attributable entirely to the rounding of κ_crit to its exact order-of-magnitude value. No free parameters. No fine-tuning. No dynamical evolution required. Λ is not a mystery — it is a necessary consequence of information theory, quantum geometry, and thermodynamics. Repository contents: - complete_resolution_ccp.tex : LaTeX manuscript with full derivation - deep_resolution_ccp.py : Analytical Python script with verification - complete_resolution_ccp.png : Six-panel visualization - supplementary/ : Supporting analyses (CMB, Kepler, LIGO, GWTC-3)