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Updated: Jan 18, 2026
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Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
Published on: July 20, 2022
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Constraints on Primordial Magnetic Fields from the Lyman-α Forest
Mak Pavičević1,2,3, Vid Iršič1,2,3,4,5,6, Matteo Viel1,2,3,4,7
1SISSA-International School for Advanced Studies, Via Bonomea 265, I-34136 Trieste, Italy.
Physical Review Letters
|September 10, 2025
Summary
This study provides the first constraints on primordial magnetic fields using Lyman-alpha forest data. The findings establish the tightest upper limits on the strength of intergalactic magnetic fields to date.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- Primordial magnetic fields are hypothesized to have originated in the early universe.
- The Lyman-alpha forest offers a unique probe of the intergalactic medium at high redshifts.
Purpose of the Study:
- To derive the first constraints on primordial magnetic fields using Lyman-alpha forest observations.
- To establish new upper limits on the strength of intergalactic magnetic fields.
Main Methods:
- Utilizing full cosmological hydrodynamic simulations.
- Analyzing over a quarter million flux power spectrum models.
- Parametrizing magnetic field influence via k_peak.
Main Results:
- A hint of extra power consistent with primordial magnetic fields (B~0.2 nG).
- A 3σ C.L. lower limit of k_peak > 30 Mpc⁻¹ under conservative noise modeling.
- The tightest bounds to date: B < 0.30 nG.
Conclusions:
- Lyman-alpha forest data provides strong constraints on primordial magnetic fields.
- The derived upper limit significantly advances our understanding of early universe magnetism.
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