The primordial helium-3 abundance from BBN exhibits constraints difficult to satisfy simultaneously with other light-element abundances (D, He-4, Li-7) in standard ΛCDM nucleosynthesis (Cyburt 2016; Iocco 2009). He-3 abundance appears to have lower production rates or different evolution than expected, suggesting underestimated stellar processing, unknown nuclear physics, or non-standard early-universe nucleosynthesis.
The standard model predicts He-3 from BBN using known nuclear-reaction rates plus the standard baryon density and expansion rate. Reconciling He-3 with the simultaneous constraints from D, He-4, and Li-7 within a single baryon-density framework demands either improved nuclear-rate measurements or modifications to BBN.
SCT replaces the hot-dense-center with a superluminal collision and the thermalized debris field. From this single change, the SCT prediction for He-3 is identical to ΛCDM via the Plasma Equivalence Theorem (P29, P30). Cascade termination before t ≈ 1 second (P40) leaves BBN to proceed under standard equilibrium thermodynamics (P42), producing the standard He-3 yield.
The cascade-thermalization context (P22, P25) supplies the baryon budget but no He-3 modification: cascade temperatures above the QCD scale erase any prior nuclei structure, including any inherited He-3 from prior cycles. After cascade termination, BBN starts fresh from primordial composition (H + neutrons) and produces He-3 at the standard yield. Pre-existing matter (P25, P28) does NOT supply pre-existing He-3 to our cycle.
Observable He-3 in stars therefore reflects standard primordial BBN production plus subsequent stellar processing, the same as ΛCDM expects. Sub-percent observational tensions are shared open issues requiring nuclear-rate or stellar-processing improvements, not a unique SCT signature. The same M2 framework that resolves the broader BBN family (recid 171, 176, 178) accounts for He-3 as an unmodified standard prediction.
If precision He-3 abundance spectroscopy + BBN nuclear-rate measurements demonstrate the He-3 tension cannot be resolved by improved systematics within the standard framework, both ΛCDM and SCT face the same challenge. The signature SCT prediction is no SCT-specific He-3 deviation from ΛCDM expectations.