> Equating the Schwarzschild radius for a given blob of matter with the event horizon of a black hole requires that the matter be static or collapsing.
If the space containing the matter is stretching does that still count as expansion?
> If the space containing the matter is stretching does that still count as expansion?
"Space stretching" is a vague pop science description that doesn't really correspond to anything in the actual physics model. So it doesn't count as anything; you should just ignore it.
I believe we shouldn't ignore it. I know about physics from pop-science mostly, so I have limited choices, either "space stretching", or (if I just ignore pop-science) "I have no clue what is happening", or I should stop doing all I'm doing now and dig into physics textbooks, to get real understanding. The last option is not really tempting, I have better ways to spend my free time, the second option doesn't seem constructive at all, so the only viable option is to not ignore vague pop-science description.
My point was to illustrate that our physics models don't agree on the nature of this expansion (Hubble tension) so using it to dismiss the fact that the observable universe is dense enough to form an event horizon seems like a stretch.
pdonis|1 year ago
"Space stretching" is a vague pop science description that doesn't really correspond to anything in the actual physics model. So it doesn't count as anything; you should just ignore it.
ordu|1 year ago
I believe we shouldn't ignore it. I know about physics from pop-science mostly, so I have limited choices, either "space stretching", or (if I just ignore pop-science) "I have no clue what is happening", or I should stop doing all I'm doing now and dig into physics textbooks, to get real understanding. The last option is not really tempting, I have better ways to spend my free time, the second option doesn't seem constructive at all, so the only viable option is to not ignore vague pop-science description.
jefb|1 year ago
Jerrrrrrry|1 year ago