Universal Symmetric Time Model (USTM): A time-symmetric alternative to inflationary cosmology

The Universal Symmetric Time Model (USTM) proposes a time-reversible cosmological structure, replacing the singular origin of the universe with a symmetric temporal inversion node (Node I). The model connects two FLRW universes with opposite time directions and introduces a CPT-symmetric scalar field under a modified Starobinsky potential. USTM reproduces observable parameters without inflation: • • • Log-symmetric modulation in the primordial power spectrum • Predictable asymmetry in B-mode polarization All predictions are compatible with Planck 2018, BAO, and LSS data. This upload includes a brief article, technical annex, comparative scientific evaluation, and a graphical spectrum co mparison.