Early galaxies and supermassive black holes discovered by the James Webb Space Telescope

Abstract Observations by the James Webb Space Telescope (JWST) have led to a series of groundbreaking discoveries that challenge our current understanding of early galaxy formation. A large number of galaxies have been surprisingly identified during the epoch of cosmic dawn, the redshift of $z\sim 11-14$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>z</mml:mi> <mml:mo>∼</mml:mo> <mml:mn>11</mml:mn> <mml:mo>−</mml:mo> <mml:mn>14</mml:mn> </mml:math> , 13.4 to 13.5 billion years ago, far exceeding theoretical predictions. Additionally, many faint AGNs hosting supermassive black holes have been discovered at $z&gt;4$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>z</mml:mi> <mml:mo>&gt;</mml:mo> <mml:mn>4</mml:mn> </mml:math> . What was happening in the early universe? This article provides an overview of these latest findings.