High-z Quasars in the R_h=ct Universe
  One cannot understand the early appearance of 10^9 solar-mass black holes
without invoking anomalously high accretion rates or the creation of exotically
massive seeds, neither of which is seen in the local Universe. Recent
observations have compounded this problem by demonstrating that most, if not
all, of the high-z quasars appear to be accreting at the Eddington limit. In
the context of LCDM, the only viable alternative now appears to be the
assemblage of supermassive black holes via mergers, as long as the seeds
started forming at redshifts >40, but ceased being created by z~20-30. In this
paper, we show that, whereas the high-z quasars may be difficult to explain
within the framework of the standard model, they can instead be interpreted
much more sensibly in the context of the R_h=ct Universe. In this cosmology,
5-20 solar-mass seeds produced after the onset of re-ionization (at z<15) could
have easily grown to M>10^9 solar masses by z> 6, merely by accreting at the
standard Eddington rate.
