PS: A slight correction to one sentence in my post below. The rest is good ....
My sentence "By the time they (the falling objects) are actually beyond the event horizon they are long gone from view." is ambiguous because it doesn't specify whose clock time is being referenced. It should be possible for the object to have already crossed the event horizon in the frame of the event horizon and there still be a faint image of the object still outside the event horizon on its way back to the external observer, not to mention the traversal time of the light going all the way back to that external observer... Second Brent's statement "..as they red shift towards invisibility" is misleading. The fading from view is not due to a red shift towards invisibility (though a red shift is occurring). The red shift is due to the object's increasing velocity deeper into the gravitational well (which slows the object's comoving clock thus reducing the frequency of the light it emits), while the fading is due to fewer photons per unit time reaching the external observer. Edgar On Sunday, January 26, 2014 10:42:22 PM UTC-5, Edgar L. Owen wrote: > > Brent, > > The way it works is that objects do NOT appear to pile up at the event > horizon. What happens is that they (as you correctly mentioned) appear to > slow their approach to the event horizon to an external observer because > the photons they emit take longer and longer to climb out of the increasing > gravity well to reach the external observer. > > But that same effect simultaneously means that that fewer and fewer > photons per unit time reach that external observer so that the object > approaching the black hole fades away proportionally to the degree it > slows. So by the time it reaches the event horizon and appears to slow to > zero it simultaneously vanishes from view. > > Thus there is NO "pile up at the event horizon" period... > > Once again my initial response to Jesse was because he claimed there was a > pile up and their isn't, and second that he claimed (or at least that's the > way I read his post) that the slowing of velocity was due to the slowing of > the clock of the object approaching the black hole which it isn't. I'm not > sure whether he actually meant that or not or I misunderstood what he said > but so long as the true picture I give above is understood it doesn't > matter. > > So there is NO pile up at the event horizon because the approaching > objects fade away as they get there in the view of an external object. By > the time they are actually beyond the event horizon they are long gone from > view. NO PILEUP! > > Edgar > > > Edgar > > On Sunday, January 26, 2014 9:09:17 PM UTC-5, Brent wrote: >> >> On 1/26/2014 11:32 AM, Edgar L. Owen wrote: >> >> Brent, >> >> There is no confusion. >> >> Sure, that's just the standard kiddy book diagram of a black hole with >> which everyone agrees (except Jesse Mazur who thinks nothing actually >> enters a black hole but instead piles up on the event horizon boundary - >> see his posts). >> >> >> I saw his posts and he quite correctly said that objects *appear* to pile >> up on the horizon as they red shift to invisibility. >> >> But that doesn't address the point of my question. >> >> What "is in there and has to come out" is the gravitational effect of >> the mass that falls in which was the point of my question and my answer. >> >> >> But that's a nonsense answer to asking the wrong question. If you're an >> observer several Scharzshild radii from a ten solar mass star and it >> collapses to a black hole, nothing changes in the gravitational field at >> your location. No "effect" had to "come out", it was already "out". >> >> Brent >> >> >> Edgar >> >> >> >> >> On Sunday, January 26, 2014 2:22:58 PM UTC-5, Brent wrote: >>> >>> On 1/26/2014 5:01 AM, Edgar L. Owen wrote: >>> >>> OK, time for THE ANSWER TO MY QUESTION of how gravity can escape from a >>> black hole.... >>> >>> Liz, Brent, and Richard, >>> >>> OK, nobody got the answer so I'll explain it myself. It's pretty >>> simple but still pretty profound and thought provoking.... >>> >>> Gravity IS what needs to be escaped. So it doesn't even make sense to >>> ask how gravity could escape ITSELF. >>> >>> There wouldn't even be a black hole if gravity hadn't already escaped >>> the black hole to create its gravitational effect. >>> >>> So what this means is that gravity is the only thing than CAN escape a >>> black hole because it is gravity itself that creates the gravitational >>> field that must be escaped! >>> >>> Thus gravity, and only gravity, can manifest freely OUTSIDE a black >>> hole the effects of its INSIDE mass. >>> >>> Thus gravity is the only thing that freely COMES OUT of a black hole >>> through the event horizon, because what stops everything else from coming >>> out is gravity itself. But obviously gravity can't stop itself from coming >>> out through the event horizon, because only its already manifesting >>> presence is what stops everything else from coming out through the event >>> horizon, but it already must have come out to stop everything else from >>> coming out... >>> >>> Thus before gravity comes out through the event horizon, there is >>> nothing to stop anything from coming out. Thus gravity can freely emerge >>> through the event horizon and only by doing so is it able to prevent >>> anything else from coming out.... >>> >>> Hope I'm explaining this clearly? >>> >>> >>> Yes, it's clear that you're confused. You think there's "something in >>> there" that has to "come out" and pull stuff in. Here's a more accurate >>> picture from Lawrence Crowell: >>> >>> >>> Think of a river with a water fall. You row your canoe at a constant >>> speed, which mimics the speed of light. The flow of water increases as it >>> approaches the falls. There is then a boundary of no return where once you >>> cross it you can’t row faster than the flow rate of the water. You are >>> inexorably going to reach the falls. A black hole is similar to that. The >>> flow of space as it evolves by the diffeomorphism of general relativity is >>> such that at the horizon that flow exceeds the speed of light. >>> >>> >>> >>> Brent >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/everything-list. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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