Chameleon-Graviton-Condensate Cosmology:A Cosmic Energy Rain (English Version)

We present Chameleon-Graviton-Condensate Cosmology (CGCC), a novel theoretical framework explaining late-time cosmic acceleration through a void-driven Bose-Einstein Condensation (BEC) of scalar graviton modes. The condensation process is dynamically triggered by a tachyonic instability (meff² < 0) arising from the trace evaluation of the modified Fierz-Pauli term. This instability drives an initial exponential growth of low-momentum modes in low-density cosmic voids. Runaway expansion is naturally bounded by a renormalizable quartic self-interaction (λ/4φ⁴), which stabilizes the field at a global vacuum expectation value φ₀ = √μ²/λ with a positive effective mass meff²(φ₀) = 2μ² > 0, yielding a stable asymptotic dark energy density V(φ₀) = -μ⁴ / (4λ).CGCC naturally satisfies strict empirical bounds across all scales. In high-density environments, the environmental mass dependence meff(ρ) and the thin-shell effect suppress fifth-force couplings, fully complying with Solar System tests (Cassini bound γ - 1 < 2.1 × 10⁻⁵ and Eöt-Wash torsion experiments). In the early universe, the high ambient density forces thermal decoupling, ensuring BBN compatibility with Δ Neff 10⁻⁴. Furthermore, CGCC reinterprets the Hubble (H₀) tension as a local measurement artifact driven by void-dominated expansion dynamics rather than a breakdown of general relativity.Finally, the model yields a distinct, falsifiable signature: a sharp gradient in the tangential weak-lensing shear profile Δ γₜ(θ) across void-to-filament boundaries, directly testable with upcoming data from the Euclid space telescope and the Vera C. Rubin Observatory (LSST).