A precise prediction for the amplitude of primordial gravitational waves, testable by LiteBIRD within this decade.
The tensor-to-scalar ratio r measures the amplitude of primordial gravitational waves relative to density perturbations in the early universe. It is the single most important observable for distinguishing models of cosmic inflation. Current CMB data (Planck + BICEP/Keck 2021) constrain r < 0.036 at 95% confidence, but have not detected a positive signal.
The STF scalar field potential, derived from the same Lagrangian that produces all other predictions, generates a slow-roll inflationary phase. The predicted tensor-to-scalar ratio is:
This is below current observational limits but within the designed sensitivity of the LiteBIRD satellite (δr ≈ 0.001), scheduled for launch around 2032.
Most inflationary models predict a wide range of r values. The STF prediction is unusually precise and derived from a theory that also predicts flyby anomalies, galaxy rotation, and particle masses. If LiteBIRD measures r = 0.004 ± 0.001, it would be consistent with only the STF among currently proposed frameworks that also address dark energy and dark matter.
LiteBIRD (Lite satellite for the study of B-mode polarization and Inflation from cosmic background Radiation Detection) is a JAXA-led CMB polarization satellite. It will map the entire sky in 15 frequency bands to search for primordial B-mode polarization — the direct signature of inflationary gravitational waves.
This prediction is falsified if LiteBIRD (or a comparable experiment) measures r > 0.01 or definitively establishes r < 0.002.