Tag: cosmology
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The First Supermassive Black Holes in the Universe
Although supermassive black holes (SMBHs) are found at the centers ofmost massive galaxies today, over 200 quasars (actively accretingSMBHs) have now been discovered at redshifts z > 6, less than abillion years after the big bang. Their discovery beginning in 2003posed serious challenges to paradigms of cosmic structure formationbecause it was not understood how such…