The Complexity

We introduce a complex-metric theory of gravity founded on a single postulate: the spacetime metric tensor is complex-valued. Physical observables are real projections of complex quantities, so the measured speed of light remains Lorentz-invariant and special relativity is recovered in the zero-imaginary limit. The framework has one free parameter: the imaginary-to-real ratio α₀ at the present epoch. This is determined from the Planck CMB lensing anomaly (AL = 6/5), and cross-checked by the Hubble tension; two internal consistency arguments — T-duality self-duality and the five-qubit quantum error-correcting code [5, 1, 3] — independently select the same value α₀ = 1/√5. From α₀ alone, with no additional free parameters, we derive: the matter density Ωₘ = √30/18 ≈ 0. 304 (1. 5σ) ; the lensing amplitude Aₗens = 6/5 = 1. 200 (0. 3σ) ; the Hubble tension resolved to 0. 72σ; the FRB autocorrelation ratio to 0. 8%; dark matter and dark energy as imaginary-sector condensates; black-hole singularity avoidance with TBH = (2/5) THawking; and galaxy spin parameter λ = (√5/3) λ_ΛCDM. The Aₗens = 6/5 prediction simultaneously resolves the Planck lensing anomaly and, via Peng twisted NbSe₂ bilayers at θ ≈ 0. 6° superconducting at 275 K; and QRAM-free Grover search with O (1) memory.