Abstract We derive the age of the universe from absolute first principles within the Generalized Mass as Twisted Time (G-MaTT) framework. Following the $E_8 \to G_2$ exceptional symmetry breaking cascade, the primordial potential $\mathcal{M}_\mu$ generates topological time braids within the 10-dimensional internal perpendicular space of the $G_2$ projection lattice. High-frequency braid modes undergo total destructive phase interference above a critical threshold dictated deterministically by the Twist-Untwist Threshold (TUT) operator. The total accumulated phase ($\Phi_{\text{total}}$) defining our cosmic domain is calculated as the product of surviving coherent low-frequency braid states and an un-tuned geometric winding factor derived from $G_2$ triality symmetries, 3D macroscopic spatial mapping, and circular phase evolution. This derivation yields an invariant prediction of $T_U \approx 13.79$ Gyr, matching empirical satellite observations without utilizing a single free cosmic density parameter ($\Omega_m, \Omega_\Lambda$) or background expansion metric.