Speaker
Description
The existence of supermassive black holes (SMBHs) of ∼ 109 solar masses in quasars at z ∼ 7.5, when the Universe was ∼700 Myr old, is an intriguing puzzle because their originremains unconstraint. It have been proposed that those SMBHs result from rapidly growing BH seeds of stellar and/or intermediate masses BHs at redshifts z ∼30. However, there is no consensus on whether such extreme rapid mass growth of BHs may be sustainable during the 600 hundred million years since the Bi Bang. Direct detections in the near and mid-infrared of galaxies and massive BHs at z = 7 to 16 with the JWST, and indirect detections of radio loud BH signals in the redshifted 21cm line of HI at z∼20 with radio arrays as SKA, may constrain the ultimate origin of the SMBHs observed up to z ∼7.5. In this talk I will discuss these issues along the lines of a review of open access published in New Astronomy Reviews 94, 101642 (2022).
