Eternal Universe Theory (EUT) - The Eternal Resonance Cosmology An Inflation-Free Cosmology with Ultralight Axions

EUT 4.4 presents a complete, inflation-free cosmological model based on a single ultralight axion (m_a = 1.5×10⁻²¹ eV) serving as Fuzzy Dark Matter. Dark matter arises via the standard vacuum misalignment mechanism. Primordial black holes with abundance f_PBH < 0.01 and masses ∼10¹⁸ kg form from quantum corpuscular fluctuations of the axion field during an early kinetic-dominated phase and act solely as gravitational seeds. In cosmic voids, wave-mechanical ground-state enhancement yields a central axion overdensity of 2.02 ± 0.11, confirmed by recent N-body simulations. The horizon and flatness problems are solved by the same early kinetic-dominated stiff-matter phase (w = +1) of the axion field, providing >60 e-folds of expansion. All major parameters (Ω_DM ≈ 0.25, effective late-time acceleration, σ₈ ≈ 0.76, S₈ ≈ 0.768) emerge naturally and match Planck, DESI, and SH0ES observations. The model is falsifiable by Euclid (void profiles), LISA (PBH mergers), and CMB-S4 (tensor modes). Confirmed by full 3D Schrödinger-Poisson simulations yielding a central overdensity of ∼2.07 (Fig. 1b)