Our knowledge of the universe could be put to the test by the surprising discoveries that the James Webb is making. The space telescope puts our cosmology to the test by finding galaxies that, theoretically, should not exist.
Out of the ordinary galaxies
Six of the first galaxies identified by James Webb are the most massive ever observed, and larger and more mature than they should be, considering their position in the universe.
A new study published in Nature Astronomy (I link it here) conducted by Mike Boylan-Kolchin from the University of Texas at Austin, wanted to test these galaxies to better understand how they formed. The findings suggest that if there are no errors in the measurements, our cosmology may have some big gaps to fill.
Redesigning cosmology
“If the mass calculations are right, we are in uncharted territory,” he says Boylan-Kolchin. “We will need something really new about galaxy formation, or a change to cosmology.”
One of the most extreme hypotheses is that the universe expanded more rapidly immediately after the Big Bang than we expect, which could imply the existence of previously unknown forces and particles.
The dilemma at a glance
Data from the James Webb Telescope suggests there may be something wrong with the dark energy and cold dark matter (ΛCDM) paradigm, which has guided cosmology for decades.
Normally, galaxies they convert about 10% of their gas into stars, but these newly discovered galaxies would appear to convert almost all of their gas.
This is a scenario that represents a departure from what scientists expected.
The next analyses
Future observations of the galaxies could better clarify their ages and masses. It could turn out that the observations are incorrect: supermassive black holes at the center of galaxies could heat them up, making them appear more massive than they actually are.
Or they may be from a later era than expected, but appear older due to some kind of problem in the images.
