A Geometric Blueprint of the Early Universe: Primordial He, D, and Li

While the predicted Helium-4 abundance represents a cornerstone success of the Standard Model, a significant discrepancy persists regarding Lithium-7, where theoretical predictions diverge by a factor of 3 to 4 from the abundances observed in the oldest halo stars. In this paper, we introduce the cosmic specific potential within an expanding 3-sphere universe, governed by a temporal function tightly coupled to the radius. Building on this alternative baseline, we assume that the modified physical conditions of the model preserve the standard primordial Helium‑4 fraction, and we investigate whether this framework can reconcile the long‑standing Lithium gap between theoretical predictions and observational data. Key Points for the Paper: Deuterium: D/H ≈ 4.20e-5 – almost compatible with observations.Helium-4: He4 ≈ 0.2416 – in excellent agreement with observations.Lithium-7: Li7 ≈ 8.6e-13 – lower than BBN (consistent with the lithium problem).Beryllium-7: fully decayed into Li7.Mass conservation: satisfied to ∼ 0.04%.Model: non-ΛCDM, decelerating 4-sphere expansion.