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

EUT 4.3 is a complete, inflation-free cosmological model based on a single ultralight axion (m_a = 1.5×10⁻²¹ eV) as Fuzzy Dark Matter. Dark matter arises from vacuum misalignment at the Planck epoch. Primordial black holes (f_PBH < 0.01) serve exclusively as gravitational seeds. Cosmic voids amplify the axion density by a factor 2.02 ± 0.11 through constructive interference of the de Broglie wave (λ_dB ≈ 0.88 kpc). The horizon and flatness problems are solved by a brief stiff-matter phase (w = 2.1) of the axion field before Planck time, realized through a standard non-canonical kinetic term P(X) = X + α X² (α ≈ 0.05). All cosmological parameters emerge without fine-tuning and are in excellent agreement with current observations (Planck, DESI, SH0ES). The model is falsifiable by Euclid (void DM profiles), LISA (PBH mergers), and CMB-S4.