Five‑Sigma Depends on the Model

Updated: 2025.09.02 1M ago 4 sources
DESI’s 3–5σ 'evolving dark energy' result assumes the discrepancy with ΛCDM is resolved by letting dark energy vary over time. But sigma levels are conditional on that modeling choice; alternative parameterizations or systematics could erase the signal. Treat headline certainty in cosmology as within‑model, not absolute truth. — It cautions that statistical certainties touted in high‑profile science often reflect model assumptions, urging media and policymakers to demand model‑robustness checks before declaring paradigm shifts.

Sources

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