Speaker
Description
The advent of the James Webb Space Telescope (JWST) has brought the study of early galaxy formation to a new level. Shortly after it began its scientific operation, JWST revealed a large number of candidate galaxies at redshift (z) greater than 11 when the universe was less than ~420 million years old, some of which could even be at z ~ 20 (age of the universe ~180 million years). This was completely unexpected by many, as the previously accepted picture (up to July 2022) would predict hardly any galaxies such early in time. Spectroscopy has confirmed some galaxies up to z = 13.2, which stimulates the building of a new consensus that galaxy formation happened much earlier in time than previously thought. Evidence from other lines of study, such as the metal abundance in galaxies at z ~ 8--9 and the confirmation of AGN at z ~ 10, all supports this new picture. This talk will give a brief overview of the up-to-date status of this frontier and will discuss the implications of this new picture to other important questions in cosmology.
