Universe Today | 2023 May 08
The James Webb Space Telescope (JWST) is revolutionizing our understanding of the early universe. With a mirror larger than Hubble and the ability to observe deep into the infrared, JWST is giving us a detailed view of that period of the universe when galaxies were just starting to form. The results have been surprising, leading some to argue that they disprove the big bang. But the big bang is still intact, as a recent study shows.
The standard big bang model for cosmology is the LCDM model, which is a universe driven to expand through dark energy (represented by Lambda in the equations), and filled with cold dark matter (CDM). It is the model most strongly supported by observational evidence thus far. But one of the things LCDM seemed to predict was that early galaxies should be small and irregular, building up through collisions to the larger galaxies we see today. This prediction came from computer simulations of the early universe.
Initial data from JWST seemed to contradict this prediction. In particular, two surveys, the JWST Advanced Deep Extragalactic Survey (JADES) and the Cosmic Evolution Early Release Science Survey (CEERS) found a handful of galaxies with redshifts z greater than 10. These galaxies are among the most distant galaxies ever observed. They are so far away we see them at a time when the universe was less than 500 million years old. Not only are these galaxies larger and more developed than expected, but they also have a high rate of star production. ...
No Tension: JWST Galaxies at ƶ >10 Consistent
with Cosmological Simulations ~ Joe McCaffrey et al
- arXiv > astro-ph > arXiv:2304.13755 < 2023 Apr 26