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A comment on Why Does the Universe Expand?. Parent comment

Re:Why Does the Universe Expand? by shevy-java on Friday September 18, 2026 @05:59AM (#49752155)
A black hole stands still? Would that not defy gravity? I mean a black hole also loses energy, right? So I would not expect it to be completely still. After all if you lose energy, you may also lose mass and shape and size - E = mc².
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Re:Why Does the Universe Expand? by PowerElectronix on Friday September 18, 2026 @06:09AM (#49752225)
Still from a far away observer. As matter gets close to the event horizon, its local clock as viewed from far away slows down to the point of freezing completely when it reaches the horizon (this you won't see from outside).

As this happens, what you see is a very hard dimming of the emited light and a very hard redshift because everything takes so long now (from the perspective of a far away observer) that the frequency of the light emitted and the luminous power emited basically go to zero (along with everything that has time in the denominator).

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Re:Why Does the Universe Expand? by chasil on Friday September 18, 2026 @09:20PM (#49762402)
There are three parameters that define a black hole: mass, spin, and charge.

There is nothing preventing spin from being zero, as far as I know.

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