Geometric Truncation of Low-Multipole CMB Power and Null B-Mode Prediction from a QCD-Scale Euclidean Instanton Bounce

The persistent lack of power at low multipoles (ℓ < 10) in the Cosmic Microwave Background (CMB) temperature anisotropy spectrum is traditionally dismissed as cosmic variance within the standard ΛCDM cosmological model. We propose that this anomaly is not a statistical fluctuation, but a strict physical truncation resulting from the universe emerging from a finite Euclidean instanton bounce at the Quantum Chromodynamics (QCD) density scale ρ_c ~ 10⁴ MeV/fm³, rather than from a point-like Big Bang singularity. Using the Null-Vector Gravity (NVG) framework, we analytically derive the radius of this Genesis instanton r_c = 1.13 km and the exact required number of e-folds N_e = ln(R_{H₀}/r_c) ≈ 53.2, bypassing the arbitrary initial conditions and scalar fields of standard inflation. The maximum comoving wavelength of primordial perturbations is strictly bounded by the physical size of the instanton, resulting in an exact mathematical suppression of the quadrupole (ℓ=2) and octupole (ℓ=3). Furthermore, because the bounce occurs at an energy scale 10⁷⁷ times lower than the Planck scale, primordial tensor perturbations are not excited, resulting in a strict null prediction for the tensor-to-scalar ratio r = 0. This provides a definitive, falsifiable target for next-generation B-mode observatories such as LiteBIRD.