The Dead Universe Theory: Effective Viscoelastic Response of Spacetime within General Relativity

Before Einstein, space was treated as a passive background. General Relativity elevated spacetime to an active geometric entity through curvature. Here we develop a deeper paradigm within the Dead Universe Theory (DUT): spacetime is modeled as a Quantum Viscoelastic Continuum (CVQ) — a material medium endowed with thermodynamic memory, dissipation, and elastic response. We formulate first principles in which the quantum vacuum behaves as a Planck-scale fluid, introduce an action principle extending Einstein–Hilbert gravity with an intrinsic viscous dissipation term, and derive a modified growth equation for cosmic structures. In the asymptotic, vacuum-dominated regime, thermodynamic self-consistency and scale invariance select a quadratic condition whose physically admissible solution yields a growth index gamma = 0.618. This value is not fitted but follows from stability, dissipation balance, and auto-similarity, providing a falsifiable, thermodynamically grounded deviation from standard LCDM growth expectations. We then evaluate this prediction against multiple independent empirical probes: (i) the Structural Natal Index (SNI), derived from JWST deep fields and SDSS DR17, indicates a demographic transition near z ≈ 2.2 consistent with late-time growth suppression; (ii) the residual quenching rate DeltaQ = 0.025 ± 0.008 Gyr^-1, not captured by feedback simulations, is quantitatively reproduced by a viscoelastic retraction rate alpha ~ 1e-18 s^-1; (iii) the cosmological dipole exceeds the kinematic expectation at 5.1 sigma (Secrest et al. 2025), consistent with an intrinsic large-scale asymmetry; and (iv) Bayesian model comparison using DESI DR2 and Euclid Quick Release 1 yields ln B = 3.2 ± 0.4, indicating a moderate-to-strong preference for DUT/CVQ over LCDM under the stated priors and likelihoods. Notes. The Structural Natal Index (SNI) is introduced in this manuscript by Joel Almeida (computational cosmologist and software architect, Ph.D.). Code for SNI estimation and galaxy-demographic tables is made available to the scientific community (see "Code and Data"). Joel Almeida also created the FOSSIL method for galaxy death analysis, also available in the ExtractoDAO Labs repository on GitHub.https://github.com/ExtractoDAO