Primordial magnetic fields may help resolve Hubble tension, study suggests

The short version

• Astrophysicists used three-dimensional simulations to model how primordial magnetic fields affected early hydrogen formation and cosmic microwave background observations.[ScienceDaily]
• The presence of early magnetic fields would alter the timing of recombination, potentially reconciling the discrepancy between indirect cosmic microwave background expansion estimates and direct supernova measurements.[ScienceDaily]
• Data analysis revealed a mild preference of 1.5 to 3.0 standard deviations for these fields, which remains short of a definitive discovery and requires further observational testing.[ScienceDaily]

Key facts

• The Hubble tension stems from conflicting expansion rate estimates: approximately 67 km/s/Mpc derived from cosmic microwave background data and roughly 73 km/s/Mpc measured via supernovae.[ScienceDaily]
• Simulations demonstrate that primordial magnetic fields would influence recombination by clumping matter and accelerating hydrogen formation, shifting the cosmic ruler used to infer expansion rates.[ScienceDaily]
• The dataset analysis shows a mild statistical preference between 1.5 and 3.0 standard deviations for early magnetic fields of about five to ten pico-Gauss today.[ScienceDaily]

Sources

Outlet counts describe coverage, not independent confirmation. Reports may share a wire service or original source.

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