There are a lot of questions about the m87 image on this site, non of them actually answer my question.
I have read this question:
For the distant observer no event horizon ever forms and the the infalling observer takes an infinite time to pass the point r=rs where the horizon would form given infinite time.
And here is the real image of an actual black hole:
Based on John Rennie's answer, the event horizon never forms to an outside observer, just like us here on Earth. So if the event horizon never forms, then that black area in the middle is the effect of something else.
Now if the event horizon never forms for us outside observers, then what is that we see in the middle area, the black part? If that is not the event horizon, then it could be maybe an effect of GR lensing or EM shielding, or any other effect?
- If an event horizon never forms for an outside observer, then what do (or don't) we see on this real image of an actual black hole?