Dark Matter from a Second Warped Throat: Gravitational Freeze‑In in the DBQTM Framework

Abstract We extend the Dual-Brane Quantum Tunneling Model (DBQTM) by introducing a second Klebanov–Strassler throat on the same Calabi–Yau manifold. The flux integers (K2,M2)=(39,35) generate a warp factor kd2≈35, producing an infrared scale AIR,2=ke−kd2≈133 GeV, identified with the mass of the lightest scalar glueball of the confined SU(35) gauge theory. This state is automatically stable, couples to the Standard Model only through gravity, and constitutes a natural dark matter candidate. Dark matter is produced via UV‑dominated gravitational freeze‑in through zero‑mode graviton exchange. The observed relic abundance ΩDMh2=0.12 is obtained for an inflationary Hubble rate Hinf∼1013 GeV, predicting a tensor‑to‑scalar ratio r∼10−3−10−2, testable by LiteBIRD and CMB‑S4. The model predicts an extremely suppressed direct‑detection cross section σSI∼10−98 cm2 and a cosmological lifetime τ∼1032 yr. The dark matter mass, relic abundance, and stability all follow from the discrete flux data of the second throat, with no continuous free parameters.