Jesse, PS: It's not my theory, it's mainstream relativity theory. Any physicist and probably some others here can set you straight....
Edgar On Sunday, January 26, 2014 12:22:58 PM UTC-5, jessem wrote: > > > > On Sun, Jan 26, 2014 at 11:49 AM, Edgar L. Owen <[email protected]<javascript:> > > wrote: > >> Jesse, >> >> No. >> >> First you have a basic misunderstanding of relativistic time in your >> first paragraph. External observers DO see objects fall through the event >> horizon of a black hole with no problem at all. They don't get stuck >> somehow to the surface of the event horizon as you suggest. They accelerate >> according to the usual laws of gravitation and fall right through the event >> horizon at ever increasing speed. >> >> The effect you are speaking of is simply that their CLOCKS SLOW (from the >> frame of the external observer) as their speed increases but primarily >> because of the increasingly intense gravitation, but their MOTION through >> the event horizon DOES NOT SLOW from the POV of the external observer. >> > > > If by "POV of the external observer" you mean what the external observer > would see if they were receiving continuous light signals from the falling > observer (rather than talking about what happens in some coordinate system > used by the external observer), then you're incorrect, the external > observer would see the falling observer inch closer and closer to the > position of the horizon but never quite reach it. This is in fact an > obvious *consequence* of the fact that the falling observer's clock is seen > to run slower and slower and never quite reach the time at which the > falling observer crossed the horizon--all observers in relativity always > agree about which events coincide at the same local point in space time, so > if there are a series of markers hovering above the horizon, all observers > must agree about the time on the falling observer's clock at the moment he > passed locally next to each marker. Thus if the falling observer noticed > his clock read 10 seconds when passing marker A, 20 seconds when passing > marker B, and 30 seconds when passing marker C, external observer must > agree that these local events coincide. So if the external observer sees > the falling observer's clock slowing, so that it takes much longer for it > to go from 20 to 30 than it took to go from 10 to 20, that means they must > also see the falling observer take much longer to cross from marker B to > marker C than he took to cross from marker A to marker B. > > If you disagree, please explain which part of the argument you disagree > with. Do you disagree with the basic principle that all observers agree on > which local events coincide, so they all agree on what the falling > observer's clock read at the moment he passed locally next to each marker? > Or do you disagree that external observers see his clock slowing in such a > way that it never quite reaches the time at which he locally crossed the > horizon? Or something else? > > Also, I'm sure it wouldn't be hard to find some references written by > physicists saying that external observers would see the falling observer > getting closer to the horizon but never quite reaching it. Are you claiming > that this is incorrect in the standard understanding of general relativity > by physicists, or are you just telling me it's incorrect in your personal > theories which disagree with mainstream physics? If the former, would you > be open to changing your mind if I could find you some such references? > > Jesse > > > > > > > > >> >> You are confusing the frames.... >> >> Second for the answer to my question of how gravity can escape the event >> horizon see my response to Liz on the Tegmark's New Book thread... >> >> Edgar >> >> >> >> On Sunday, January 26, 2014 10:16:07 AM UTC-5, jessem wrote: >>> >>> According to general relativity, neither gravity nor electric fields >>> actually "come out of" the black hole's event horizon, rather the gravity >>> and EM field felt by observers outside the horizon is a sort of frozen >>> snapshot of the gravity/EM fields from all the matter that approached the >>> horizon in the past. Keep in mind that external observers can never >>> actually see anything cross the horizon, instead they see it moving more >>> and more slowly as it gets arbitrarily close to the horizon--the redshift >>> is continually increasing as it approaches horizon so in practice an >>> external observer can't see an object stuck on the horizon forever, but in >>> principle you could if you could detect light with arbitrarily huge >>> wavelengths, and if light was a classical EM wave rather than being >>> quantized into photons. >>> >>> The Usenet Physics FAQ at http://math.ucr.edu/home/baez/physics/ has >>> some good summaries: >>> >>> http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/ >>> black_gravity.html >>> >>> 'How does the gravity get out of a black hole? >>> >>> 'Purely in terms of general relativity, there is no problem here. The >>> gravity doesn't have to get out of the black hole. General relativity is a >>> local theory, which means that the field at a certain point in spacetime is >>> determined entirely by things going on at places that can communicate with >>> it at speeds less than or equal to c. If a star collapses into a black >>> hole, the gravitational field outside the black hole may be calculated >>> entirely from the properties of the star and its external gravitational >>> field before it becomes a black hole. Just as the light registering late >>> stages in my fall takes longer and longer to get out to you at a large >>> distance, the gravitational consequences of events late in the star's >>> collapse take longer and longer to ripple out to the world at large. In >>> this sense the black hole is a kind of "frozen star": the gravitational >>> field is a fossil field. The same is true of the electromagnetic field >>> that a black hole may possess.' >>> >>> They then go on to discuss how the picture is altered by virtual >>> particles in quantum field theory, but the above is a good explanation of >>> how it works with classical general relativity and classical >>> electromagnetism. And this entry from the FAQ discusses how in general >>> nothing is actually seen to cross the horizon by external observers: >>> >>> http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/fall_in.html >>> >>> 'Won't it take forever for you to fall in? Won't it take forever for >>> the black hole to even form? >>> >>> 'Not in any useful sense. The time I experience before I hit the event >>> horizon, and even until I hit the singularity—the "proper time" calculated >>> by using Schwarzschild's metric on my worldline—is finite. The same goes >>> for the collapsing star; if I somehow stood on the surface of the star as >>> it became a black hole, I would experience the star's demise in a finite >>> time. >>> >>> ... >>> >>> 'A more physical sense in which it might be said that things take >>> forever to fall in is provided by looking at the paths of emerging light >>> rays. The event horizon is what, in relativity parlance, is called a >>> "lightlike surface"; light rays can remain there. For an ideal >>> Schwarzschild hole (which I am considering in this paragraph) the horizon >>> lasts forever, so the light can stay there without escaping. (If you >>> wonder how this is reconciled with the fact that light has to travel at the >>> constant speed c—well, the horizon is traveling at c! Relative speeds in GR >>> are also only unambiguously defined locally, and if you're at the event >>> horizon you are necessarily falling in; it comes at you at the speed of >>> light.) Light beams aimed directly outward from just outside the horizon >>> don't escape to large distances until late values of t. For someone at a >>> large distance from the black hole and approximately at rest with respect >>> to it, the coordinate t does correspond well to proper time. >>> >>> 'So if you, watching from a safe distance, attempt to witness my fall >>> into the hole, you'll see me fall more and more slowly as the light delay >>> increases. You'll never see me actually get to the event horizon. My >>> watch, to you, will tick more and more slowly, but will never reach the >>> time that I see as I fall into the black hole. Notice that this is really >>> an optical effect caused by the paths of the light rays. >>> >>> 'This is also true for the dying star itself. If you attempt to witness >>> the black hole's formation, you'll see the star collapse more and more >>> slowly, never precisely reaching the Schwarzschild radius. >>> >>> 'Now, this led early on to an image of a black hole as a strange sort of >>> suspended-animation object, a "frozen star" with immobilized falling debris >>> and gedankenexperiment astronauts hanging above it in eternally slowing >>> precipitation. This is, however, not what you'd see. The reason is that >>> as things get closer to the event horizon, they also get dimmer. Light >>> from them is redshifted and dimmed, and if one considers that light is >>> actually made up of discrete photons, the time of escape of the last photon >>> is actually finite, and not very large. So things would wink out as they >>> got close, including the dying star, and the name "black hole" is >>> justified.' >>> >>> >>> >>> >>> On Sun, Jan 26, 2014 at 9:36 AM, Richard Ruquist <[email protected]>wrote: >>> >>>> Edgar, >>>> >>>> Electric fields also come out if the BH singularity has a charge. >>>> Richard >>>> >>>> >>>> On Sun, Jan 26, 2014 at 8:01 AM, Edgar L. Owen <[email protected]> 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? >>>>> >>>>> Edgar >>>>> >>>>> >>>>> >>>>> On Saturday, January 25, 2014 1:29:45 AM UTC-5, Liz R wrote: >>>>>> >>>>>> On 25 January 2014 16:31, meekerdb <[email protected]> wrote: >>>>>> >>>>>>> On 1/24/2014 4:41 PM, Edgar L. Owen wrote: >>>>>>> >>>>>>>> Brent, >>>>>>>> >>>>>>>> No, my proposed dark matter effect has nothing to do with black >>>>>>>> holes. Black holes are caused by accumulations of actual visible >>>>>>>> matter, >>>>>>>> not by the Hubble expansion of space... >>>>>>>> >>>>>>>> However I do have a question for you. Since gravitational changes >>>>>>>> propagate at the speed of light how does the mass inside a black hole >>>>>>>> produce gravitational effects outside the black hole? If light can't >>>>>>>> come >>>>>>>> out how can gravitational effects come out? >>>>>>>> >>>>>>> >>>>>>> You are thinking of gravity as mediated by force particles, like >>>>>>> photons mediate the EM forces. But (at least classically) gravity >>>>>>> isn't a >>>>>>> force, it's just a shape of space and as I responded to Liz, there's >>>>>>> not >>>>>>> mass in a black hole, no T_u_v term in the Einstein equation. It's a >>>>>>> vacuum solution. That's why it doesn't make any different what falls >>>>>>> in to >>>>>>> create the black hole. The effects outside the event horizon are just >>>>>>> that >>>>>>> the space is warped there just *as if* the black hole were a massive >>>>>>> object. >>>>>>> >>>>>>> I believe Richard Feynmann was asked the same question (about how >>>>>> gravity "escapes" a black hole). Of course gravity WAVES can't escape a >>>>>> black hole... >>>>>> >>>>> -- >>>>> 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. >>>> 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. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected]<javascript:> >> . >> 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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