Astronomy Test Objective 1: Origins of the Universe Multiple Choice
... but instead grew on a diet of gas and stars controlled by their host galaxies in the beginning years of the universe. An initial look at 30 galaxies indicates that black holes do not precede a galaxy’s birth, but instead evolve with the galaxy by trapping an amazingly exact percentage (0.2) of the m ...
... but instead grew on a diet of gas and stars controlled by their host galaxies in the beginning years of the universe. An initial look at 30 galaxies indicates that black holes do not precede a galaxy’s birth, but instead evolve with the galaxy by trapping an amazingly exact percentage (0.2) of the m ...
CMBR and BH evaporation
... Of course, the CMBR will dominate in the case when the BH horizon’s temperature TH < TCMBR. Since for a BH having the mass of Earth (6×1024 kg) the Hawking’s temperature is2 TH ≈ 0.02 K and r ≈ 10 mm we can find that for BH having TH ≈ 3 K its gravitational radius has to be less than 1.5 m ≈ 0.01 m ...
... Of course, the CMBR will dominate in the case when the BH horizon’s temperature TH < TCMBR. Since for a BH having the mass of Earth (6×1024 kg) the Hawking’s temperature is2 TH ≈ 0.02 K and r ≈ 10 mm we can find that for BH having TH ≈ 3 K its gravitational radius has to be less than 1.5 m ≈ 0.01 m ...
Active Galactic Nuclei
... The conversion of gravitational PE into light is not expected to be 100% efficient. But, even if the efficiency is ~ 10%, then dm/dt increases to only 1 M/yr which is still a trivial amount. So, the high luminosity is not due to a high infall rate but rather is due to the enormous depth of the grav ...
... The conversion of gravitational PE into light is not expected to be 100% efficient. But, even if the efficiency is ~ 10%, then dm/dt increases to only 1 M/yr which is still a trivial amount. So, the high luminosity is not due to a high infall rate but rather is due to the enormous depth of the grav ...
