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A comment on Possible detection of a black hole with a mass thought to be impossible. Parent comment

Re:Possible detection of a black hole with a mass thought to... by garmaine on Wednesday September 02, 2020 @01:00PM (#24355201)
No. In fact, the entire observable universe is a black hole: the Schwarzschild radius of the mass of the observable universe is greater than the observable size, meaning by the technical definition of a black hole we are living within one: light from Earth sent into the darkest region of the sky will not escape the gravitational pull of the whole universe, even before considering expansion rates.
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Re:Possible detection of a black hole with a mass thought to... by ptspin on Wednesday September 02, 2020 @01:22PM (#24355464)
The Schwarzschild radius for the mass of the observable universe is about 13.7 Billion Light Years while the observable universe is about 93 Billion Light Years across (radius ~46 Billion Light Years). So the universe is not itself a black hole (until you take expansion rates into account)
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Re:Possible detection of a black hole with a mass thought to... by garmaine on Wednesday September 02, 2020 @01:24PM (#24355506)
I think you have that backwards--you have to take expansion into account for the "observable" universe to be that large, since the age of the universe is only 13.7 billion years.
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