Primordial Magnetic Fields May Resolve Universe's Expansion Discrepancy

New research suggests that tiny magnetic fields formed shortly after the Big Bang could explain the long-standing 'Hubble tension' – the disagreement over the universe's expansion rate. Detailed simulations indicate these primordial fields might have altered hydrogen formation in the early universe, influencing the cosmic microwave background and its inferred expansion rate. The study was published in Nature Astronomy in 2025.