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From the gravitational time dilation theory we know that at event horizon of a black hole the time should stop completely. However all the physics phenomenon we know (at macro level) e.g laws of motion are based on time so I have following questions bugging me:

  1. Since all matter appears to interact with each other physically (collision, friction etc) over time, these phenomenon would not happen at event horizon and further. Because there is no flow of time so there should not be any motion and things pushing each other or getting heated up due to friction etc because there is no time flow which should lead to absence of events

  2. Since there is no time flow the matter being sucked in would not push other matter at event horizon because the time stops there and motion shouldn't happen. This means that all the matter that is being sucked in could actually be a unimaginably thin layer with unimaginable density at the event horizon which never falls in further.

Edit: What's even more mind boggling is the fact is some of these black holes are known to be moving around at millions of kilometres per hour in Earth's time perspective even though their time is stopped. So how can it move around in zero time? Or is it moving in T→0 time?

Are the above conclusions correct (or do they even make any sense), assuming that a black hole doesn't obey some unknown physics?

user1062760
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  • Time is a local quantity that is measured by a local clock. That clock doesn't care about what is happening somewhere else, at all, and neither do local physics phenomena. What happens "inside" black holes is completely unknown, it's not even certain that there is an "inside". – CuriousOne Oct 29 '15 at 00:58
  • @CuriousOne But by that logic any event at event horizon or below will take infinite amount of time which when seen by any observer will never happen even after end of the universe. – user1062760 Oct 29 '15 at 01:02
  • Like I said, there is no such thing as one time. There are infinitely many times, each one measured by its own clock in its own system of reference. If you look up the details of what happens to clocks at the event horizon, then you will see that absolutely nothing special happens there, either. A clock that passes trough the event horizon keeps ticking away perfectly fine for a finite amount of time. – CuriousOne Oct 29 '15 at 01:04
  • @CuriousOne So I understand that means an observer outside event horizon would never see things falling in after event horizon in that case he should see all the matter falling in being deposited at event horizon in an infinitely thin layer which will appear to never interact with anything – user1062760 Oct 29 '15 at 01:10
  • Yes, but where the event horizon is depends on the observer. It's not some hard surface that things are falling on to to stop dead. Observers falling towards the black hole will have a different event horizon than the stationary observer at infinity. The future around a black hole is just as diverse as the future everywhere else. This gets a lot more complicated for charged black holes with large angular momentum. – CuriousOne Oct 29 '15 at 01:22
  • time stoppage is from the point of view of distant observers (for objects reaching the horizon), not to the one of local observers. – Fabrice NEYRET Oct 29 '15 at 22:56
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    Possible duplicate of Can matter really fall through an event horizon? – DilithiumMatrix Nov 06 '15 at 17:15
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    Duplicates: http://physics.stackexchange.com/q/63426/, http://physics.stackexchange.com/q/79054/, http://physics.stackexchange.com/q/48026/ – DilithiumMatrix Nov 06 '15 at 17:16

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