How Supermassive Black Holes Form by z ~ 7
Over 100 quasars have now been discovered at z > 6, less than a Gyr after the Big Bang. The discovery of supermassive black holes (SMBHs) by this epoch posed severe challenges to current theories of structure formation because it is not known how objects so massive appeared by such early times. However, we have now developed numerical simulations that show that these quasars can form from direct collapse black holes at z ~ 20 if they are fed by strong, cold accretion streams, like those thought to fuel the rapid growth of some galaxies at later epochs. I will discuss these simulations and formation channels for DCBHs at high redshift. I will also discuss prospects for their detection in the NIR and at 21 cm by Euclid, JWST and the SKA.