- #1
Matthew Opitz
- 3
- 0
Hello. Let me start off by saying that I am new here and that I am not actually a physics major. Still, this stuff interests me.
So, I was watching this clip of that good ol' documentary about Stephen Hawking,
And when Hawking was talking about how the image of something falling into a black hole would slow down from the perspective of an outside observer, and how, from the perspective of the infalling object, the rest of the world would speed up infinitely, I became confused about how the particle could ever actually get around to falling into the black hole.
I was pleased to find that my questions were not new:
http://www.wired.com/wiredscience/2007/06/black-holes-don/
http://blogs.discovermagazine.com/badastronomy/2007/06/19/news-do-black-holes-really-exist/
So, this is not meant to be a post about some personal theory or anything, but I just can't figure out why the following scenario wouldn't be the case:
Because of time dilation, an outside observer never actually witnesses the black hole forming. The witness sees matter collapsing into itself and asymptotically approaching, but never quite arriving at, the certain critical density at which the event horizon would form. But the observer never actually witnesses the event horizon form.
From the perspective of the person falling along with the self-condensing matter and approaching the formation of a black hole, time goes on at the same normal rate locally, but still the person or particle will never get around to experiencing the formation of an event horizon or black hole because the observed time of stuff outside of the condensing black hole will speed up infinitely. The rest of the universe, then, will end in that last second before the particle ever quite makes it to forming an event horizon (or rather, time in the outside universe will appear to pass more and more quickly towards infinity as that 1 second elapses for the innermost particle).
So even if there is no end to the universe, there's no problem.
In any case the black hole would eventually evaporate, right? Even without Hawking radiation, wouldn't the black hole eventually evaporate just from quantum tunneling? Consider:
An innermost particle of the condensing ball of matter is 1 picosecond away from forming a black hole. As that innermost particle gets closer and closer to forming a black hole, and as spacetime gets more and more sharply warped towards forming an event horizon (but not quite doing so), the outside universe will appear to accelerate infinitely. First, at 0.9 picoseconds until event horizon formation, the innermost particle will witness particles at a distance of, let's say, 1 meter outwards, accelerate in time towards infinite rate of time (as the spacetime within that 1 meter span approaches infinite, singularity-like warping (but not quite reaching that). Although the probability is extremely low that the particle at 1 meter's distance will escape the gravity well of the massive ball of matter and quantum tunnel out of the entire collapsing ball of matter, that probability is still nonzero. Furthermore, as time for this 1m distant particle appears to accelerate infinitely from the perspective of the innermost particle, that innermost particle will witness the 1m distant particle as having a number of "chances" to quantum tunnel out of the gravity-well that approaches infinity. It then becomes a certainty that the innermost particle will witness the 1m distant particle being ejected from the gravity well before those 0.9 picoseconds have elapsed for the innermost particle.
Let's go down to 0.00001 picoseconds left until the innermost particle gets compressed to the density necessary to form an event horizon. At this point, spacetime becomes so locally warped that even a particle 0.00001 picometers further outwards from the center will be perceived as having its time accelerate to infinity. From the perspective of the innermost particle, the .00001 picometer distant particle gets a number of chances to quantum-tunnel out of the gravity-well that approaches infinity. That 0.0001 picometer distant particle, from the perspective of the innermost particle, eventually does escape as well.
Now all that's left of the condensing ball of matter (the formerly soon-to-be black hole) is that innermost particle. The density required to form a black hole is no longer there, so spacetime goes back to its "normal" level of gentle warping, and time in the rest of the universe goes back to a more "normal" pace, and that innermost particle never gets to experience the formation of an event horizon or black hole, even though at one point it got asymptotically-close to doing so before the rest of the layers around it accelerated in time towards infinity and evaporated away due to a nearly-infinite number of quantum tunneling chances.
And all of this condensation and evaporation took place in the span of 1 second, from that innermost particle's perspective. Meanwhile, the rest of the outside universe has aged millions, perhaps billions, perhaps trillions, perhaps quadrillions of years (however long it takes a black hole to evaporate through quantum tunneling).
What this would mean for physics is that we no longer have to worry about what the universe or spacetime is like at a singularity, because singularities never get a chance to form (even though we might spot things in the universe with our telescopes that have a gravitational signature that is asymptotically-similar to singularities). There is never an escape velocity anywhere in the universe that is greater than the speed of light, and there is never any lost information or information paradox.
I don't understand, why would this not work?
Thanks for any feedback!
So, I was watching this clip of that good ol' documentary about Stephen Hawking,
And when Hawking was talking about how the image of something falling into a black hole would slow down from the perspective of an outside observer, and how, from the perspective of the infalling object, the rest of the world would speed up infinitely, I became confused about how the particle could ever actually get around to falling into the black hole.
I was pleased to find that my questions were not new:
http://www.wired.com/wiredscience/2007/06/black-holes-don/
http://blogs.discovermagazine.com/badastronomy/2007/06/19/news-do-black-holes-really-exist/
So, this is not meant to be a post about some personal theory or anything, but I just can't figure out why the following scenario wouldn't be the case:
Because of time dilation, an outside observer never actually witnesses the black hole forming. The witness sees matter collapsing into itself and asymptotically approaching, but never quite arriving at, the certain critical density at which the event horizon would form. But the observer never actually witnesses the event horizon form.
From the perspective of the person falling along with the self-condensing matter and approaching the formation of a black hole, time goes on at the same normal rate locally, but still the person or particle will never get around to experiencing the formation of an event horizon or black hole because the observed time of stuff outside of the condensing black hole will speed up infinitely. The rest of the universe, then, will end in that last second before the particle ever quite makes it to forming an event horizon (or rather, time in the outside universe will appear to pass more and more quickly towards infinity as that 1 second elapses for the innermost particle).
So even if there is no end to the universe, there's no problem.
In any case the black hole would eventually evaporate, right? Even without Hawking radiation, wouldn't the black hole eventually evaporate just from quantum tunneling? Consider:
An innermost particle of the condensing ball of matter is 1 picosecond away from forming a black hole. As that innermost particle gets closer and closer to forming a black hole, and as spacetime gets more and more sharply warped towards forming an event horizon (but not quite doing so), the outside universe will appear to accelerate infinitely. First, at 0.9 picoseconds until event horizon formation, the innermost particle will witness particles at a distance of, let's say, 1 meter outwards, accelerate in time towards infinite rate of time (as the spacetime within that 1 meter span approaches infinite, singularity-like warping (but not quite reaching that). Although the probability is extremely low that the particle at 1 meter's distance will escape the gravity well of the massive ball of matter and quantum tunnel out of the entire collapsing ball of matter, that probability is still nonzero. Furthermore, as time for this 1m distant particle appears to accelerate infinitely from the perspective of the innermost particle, that innermost particle will witness the 1m distant particle as having a number of "chances" to quantum tunnel out of the gravity-well that approaches infinity. It then becomes a certainty that the innermost particle will witness the 1m distant particle being ejected from the gravity well before those 0.9 picoseconds have elapsed for the innermost particle.
Let's go down to 0.00001 picoseconds left until the innermost particle gets compressed to the density necessary to form an event horizon. At this point, spacetime becomes so locally warped that even a particle 0.00001 picometers further outwards from the center will be perceived as having its time accelerate to infinity. From the perspective of the innermost particle, the .00001 picometer distant particle gets a number of chances to quantum-tunnel out of the gravity-well that approaches infinity. That 0.0001 picometer distant particle, from the perspective of the innermost particle, eventually does escape as well.
Now all that's left of the condensing ball of matter (the formerly soon-to-be black hole) is that innermost particle. The density required to form a black hole is no longer there, so spacetime goes back to its "normal" level of gentle warping, and time in the rest of the universe goes back to a more "normal" pace, and that innermost particle never gets to experience the formation of an event horizon or black hole, even though at one point it got asymptotically-close to doing so before the rest of the layers around it accelerated in time towards infinity and evaporated away due to a nearly-infinite number of quantum tunneling chances.
And all of this condensation and evaporation took place in the span of 1 second, from that innermost particle's perspective. Meanwhile, the rest of the outside universe has aged millions, perhaps billions, perhaps trillions, perhaps quadrillions of years (however long it takes a black hole to evaporate through quantum tunneling).
What this would mean for physics is that we no longer have to worry about what the universe or spacetime is like at a singularity, because singularities never get a chance to form (even though we might spot things in the universe with our telescopes that have a gravitational signature that is asymptotically-similar to singularities). There is never an escape velocity anywhere in the universe that is greater than the speed of light, and there is never any lost information or information paradox.
I don't understand, why would this not work?
Thanks for any feedback!
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