Gravity Is Not Quantum Measurement, Decoherence, and the Cosmological Constant as Geometric Projection in Randall–Sundrum Geometry

We propose that in a Randall–Sundrum warped extra dimension with Z₂ orbifold symmetry [1], three foundational problems—the quantum measurement problem, the incompatibility of general relativity and quantum mechanics, and the cosmological constant catastrophe—resolve simultaneously from a single geometric principle: cross-surface and cross-bulk information transfer is imperfect, and gravity reads the full five-dimensional geometry while electromagnetic instruments read only one brane surface. The Born rule |ψ|² emerges as the partial trace over bulk degrees of freedom inaccessible to surface-bound instruments—a theorem, not a postulate. Wavefunction collapse is surface projection of a five-dimensional state. Gravity, which reads total bulk deformation without selecting a surface, cannot cause collapse and is fundamentally classical—not a quantum force. The graviton does not exist. The cosmological constant is exponentially suppressed by the warp factor: ρ_Λ ~ v⁴ × e^(−3kL) ≈ 10⁻³⁹ GeV⁴, reducing the vacuum catastrophe from 10¹²³ to ~10⁸ (the observed value is 10⁻⁴⁷ GeV⁴). The seesaw mechanism is geometric: the heavy partner at ~10¹⁵ GeV is the brane’s depth, not a particle. We predict: no gravitationally induced entanglement, no gravitational decoherence, no gravitational wave shot noise, and no Planck-scale dispersion—four tests distinguishable from Penrose–Diósi objective collapse, string theory, and loop quantum gravity.