MinneapolisHelium formed within the universe’s first five minutes.
The measurement tests physics from an era nothing else can reach.
The helium fraction left behind depends on how fast the early universe expanded, constraining any undiscovered light particles.
The finding sharpens the search for particles beyond the Standard Model, with no timeline for confirmation.
How each outlet framed it
- Phys.org
- measures primordial helium abundance to 0.5% precision (threefold improvement) using 130-hour Large Binocular Telescope survey of pristine galaxies, validating Standard Model
Sources: Phys.org