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I have struggled-with, but hopefully comprehended, Einstien's theory (now, of course, conclusively proven) but must reiterate that this is not the point of my query, which is that, if the following excerpt from imatfaal's post:"everything that has ever fallen into the black hole is smeared out over the event horizon and stuck in time" is correct then an observer at a safe distance from said event horizon would have a visual indication that a black hole was present?Unless I'm missing something (or the subject is beyond my intellectual abilities) and it's taken as a given that black holes are invisible ... then that statement must be wrong.Sorry to be appearing stubborn here ... but a black hole cannot be invisible if 'frozen images in time' of all the debris that has disappeared into it is smeared-out over the event horizon ... surely?Thanks for the feed-back,Raw
The layer of smeared out stuff is equal to the increase in the schwarzchild radius - so the ev does seem to grow.
Graham - remember that the increase in the EV through the smearedout remains of Alice is merely a crutch to support that fact that simultaneiety has broken down; from Alice's perspective she has already crossed horizon and whatever happens at the "singularity" has happened to her already. But we are still observing Alice crossing - yet we know from her perspective she has already added to the mass of the black hole - so we have to find an explanation that fits both (it's a cludge but it works); bear in mind that whilst the picture we see of the event horizon is massively time dilated compared to our external accelerated reference frame, any changes affecting our measurements of the gravity (and thus eh etc) propagate at c.I am struggling to get my head round the second part of your question - I don't understand why the surrounding stars should make a difference to the measurement of the SR
The SR is directly proportional the mass within it according to theory:r = 2GM/c^2So it should grow. The mass is not exactly "removed" from the universe as it still has a gravitational field and still has properties of momentum, angular momentum and charge (as theory would have it). My comments were about "how" it grows and "when" as perceived from a distant observer. There seems a point when (as Matthew puts it) part of the "smeared out" falling object(s) become within the EH's expanding EH.
As the process slow down as seen from Earth the light will redshift. I don't know how far it can redshift before becoming impossible to measure but Raw is right. There will be a point where we can't get any more information of that object as the 'clock' stops to us observing it. And that clock do stop somewhere before passing the Even horizon as observed by us.
It's a confusing subject. I think you are right that the BH does grow to encompass some of the matter very close to the EH (as perceived by a distant observer) though. This seems out of kilter with the formula, but then that is derived from a perfectly spherically symmetric Schwartzchild metric. I have to say I am not sure about this, but if this were not the case then you have to wonder how a BH can ever be formed because accreting matter would always take an infinite time as observed from a distance