The Evaporating Universe I: A dissipation principle — Resolving cosmic tensions without additional free parameters

The ΛCDM model faces two persistent tensions: the Hubble constant measured locally (H₀ = 73.17 ± 0.86 km/s/Mpc, SH0ES) disagrees at 5.8σ with the CMB inference (67.36 ± 0.54), and weak-lensing surveys measure S₈ values ~2.6σ below the Planck prediction. We present the Evaporating Universe (EU), an interacting dark energy model in which a Gribov–Zwanziger ghost condensate mediates a continuous CDM→vacuum energy transfer: Q = −λε(z)Hρ_cdm. The dissipation fraction (λ = 2/3), logistic exponent (b = 19/36), transition redshift (z_trans ≈ 5.986), bare amplitude (ε_bare ≈ 0.0543), and effective coupling (ε_IR ≈ 0.0426) are derived from Effective Field Theory in curved spacetime; no parameter is fitted to data (Δk = 0). The model is implemented in a modified CLASS Boltzmann solver and validated through six Cobaya MCMC runs (~380,000 total samples; all six converge at R−1 < 0.01) against Planck CMB, DESI DR2 BAO, Pantheon+ SNe, SH0ES, and DES-Y3 weak lensing. The CDM drain yields H₀(LKI) = 72.71 ± 0.30 km/s/Mpc, within 0.52σ of SH0ES. The S₈ tension is traced to a systematic bias in the ΛCDM lensing kernel; forward-modeling the EU kernel reduces the DES-Y3 discrepancy from ~2.6σ to 1.03σ. Including DES-Y3 data directly in the MCMC confirms compatibility at 0.58σ. A 1024³-particle Gadget-4 N-body simulation validates the drain signature in P(k), and model selection yields ΔAIC = −6.88. We present ten zero-parameter predictions for Euclid DR1, LSST Y1, and DESI DR3, one of which — the CPL equation-of-state mirage (w₀ = −0.855 with CMB prior) — already matches the DESI DR2 measurement (w₀ = −0.838 ± 0.055) at 0.3σ. The EU resolves both cosmological tensions simultaneously, with zero additional free parameters.