The universe's first magnetic fields were 'comparable' to the human brain — and still linger within the 'cosmic web'

The universe's earliest magnetic fields were likely much weaker than previously thought, comparable to electrical activity in the human brain. Researchers used 250,000 simulations to determine these primordial fields maxed out at 0.00000000002 gauss—billions of times weaker than a refrigerator magnet. Remnants still exist within the cosmic web connecting all galaxies. Scientists believe these fields became intertwined with the cosmic web during the universe's initial inflation, explaining magnetism found between galaxies. These findings align with cosmic microwave background observations, with further research possible using the James Webb Space Telescope.