# Gravitational Time Dilation

Discussion in 'Astronomy, Exobiology, & Cosmology' started by RajeshTrivedi, May 4, 2015.

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1. ### RajeshTrivediValued Senior Member

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Sweetpea / krash661 / Kristoffer,

Abuses and fights are always interesting and difficult to resist (the temptation of getting in)......

Q. what is the significance of time dt inside EH for a person on Earth ??

For example Brucep says for that imaginary UMBH it takes 72 Hrs, what is this seventy two hours for a person on Earth ??

(Request please do not budge the thread with terms like proper time, coordinate time, spatial nature etc, if possible try answering in a language which a layman can understand, because a layman understands time).

PS : If you agree that time inside EH has no meaning with respect to time outside EH....then does it not mean that Physics inside EH has no meaning with Physics outside EH ? There are four coordinates dx, dy, dz, dt..........first three are same everywhere, dx = dz = dy = 1cm is 1cm inside EH and outside EH........then what so special about dt (or cdt) ?? Are we saying that t is a special dimension at will ?

3. ### RajeshTrivediValued Senior Member

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OnlyMe says....

......................I do know that if GR is correct in its prediction that mass can collapse, creating an event horizon at Rs and a singularity at R=0, no material object can exist inside Rs. Likely even inside a radius somewhat greater than 4/3Rs...................

1. Why if GR........ ??

2. And this 4/3 Rs is the latest learning of yours, you are yet to answer how the object compact to r = 0 from a size of r > 4/3 Rs ??

(Not even a single Prof said that .............if GR is correct..............)

PS : Every time I feel that there is some rationality in your approach, you back out.......

5. ### OnlyMeValued Senior Member

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Rajesh, GR makes predictions all of the way to R=0, but nothing inside of an event horizon has been obese red or otherwise confirmed, so it is still a prediction and it is appropriate to say, if GR is correct when referencing a prediction that has not been confirmed.

So no you won't hear the professors use wording like that. Nor would you hear me use wording like that discussing GR with them. But when you put my comment which was a response to you, into context (go back and read the whole post again if you need to), then you should see how that wording fits.., in context.

7. ### RajeshTrivediValued Senior Member

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Ok, lets flow with you....

When we talk of prediction in this context, we talk of collapse of object from EH to r = 0, this is what you are saying. Isn't it ??

Now collapse from EH to r = 0 is a physical real phenomenon, it will take some time, say it takes 'dt' seconds, lot of calculations are available here and there.....now the question is what is that 'dt' for a person on Earth ??

(If I cannot associate meaningful time with an event, then what is the significance of that event ? If I cannot associate meaningful time in my frame, then what is the significance of the collapse prediction of GR ??)

PS : Please remember that one member (although erroneously) keeps on saying that singularity must be spinning, fine, spinning implies revolutions per second, so how much is this per second in Earth's time ?? (or even external to EH). How an object (say inside of EH) can influence outside EH in real time, when its own time has no link with external time ??

Last edited: May 9, 2015
8. ### OnlyMeValued Senior Member

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Rajesh, every time you bring up the issue you prove you have no idea what you are talking about.

You are asking the question, it would seem from your past posts, as if there is some classical answer. As if whatever time is inside an event horizon can be compared to some everyday classical experience of time here on earth. That is not the case... And it is clear that you don't understand enough about GR and gravitational time dilation, without the complexities introduced by event horizons and black holes, for anyone to have any chance of explaining it to you.., if they were so inclined.

9. ### RajeshTrivediValued Senior Member

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What it means is that......you don't know, you are just babbling.

10. ### OnlyMeValued Senior Member

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A second is a local experience based measure of time!
Actually what it means is that you are just babbling!

Stop long enough to make sense. Until then I am done.

11. ### RajeshTrivediValued Senior Member

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Right, dt = 1 Second locally ??

How an event which has taken place locally in one second will demonstrate itself externally ??

Is it sufficient to say that both local and external times are not at all related ?? Then can you explain if the time on the either side itself is not connected, how the effect of the inside can manifest outside ??

You are not done, you are running away !! There are many people who understand the maths about coordinate times on both the sides, the proper time locally........but they are silent beyond that.......The conclusion is something is amiss somewhere ??

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That's not very original OnlyMe, as at least two Professors, or is it three?, have said virtually the same thing.

In reality, you are not going to shift this bloke, as is the case with most cranks and trolls.

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No the conclusion is that your posts reflect nothing but nonsense and pseudoscience just like your unscientific paper.
People don't run away Rajesh...Really grow up and stop talking like a child! People just get tired of trying to educate mugs and those that don't want to be educated. That's a fact. Otherwise we would have a lot more intelligent people in on your threads. But they observe how when shown you are wrong, you resort to insults and accusations that you cannot support....so they decide to let you stew in your own shit.

14. ### RajeshTrivediValued Senior Member

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I am willing to shift........you tell me from your scientific common sense and reasonableness...that if time is disjoint on either side of EH.....then how one side can create impact on the other side ?? How BH can influence the orbital dynamics of stars in the vicinity but outside EH ?

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Simply because gravity is a fossil field and is nonlinear.
But they are facts that I have told you before and are supported by many references.

16. ### RajeshTrivediValued Senior Member

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How does that resolve the issue of disjoint of time on either side of EH ??

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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.

Often this question is phrased in terms of gravitons, the hypothetical quanta of spacetime distortion. If things like gravity correspond to the exchange of "particles" like gravitons, how can they get out of the event horizon to do their job?

Gravitons don't exist in general relativity, because GR is not a quantum theory. They might be part of a theory of quantum gravity when it is completely developed, but even then it might not be best to describe gravitational attraction as produced by virtual gravitons. See the physics FAQ on virtual particles for a discussion of this.

Nevertheless, the question in this form is still worth asking, because black holes can have static electric fields, and we know that these may be described in terms of virtual photons. So how do the virtual photons get out of the event horizon? Well, for one thing, they can come from the charged matter prior to collapse, just like classical effects. In addition, however, virtual particles aren't confined to the interiors of light cones: they can go faster than light! Consequently the event horizon, which is really just a surface that moves at the speed of light, presents no barrier.

I couldn't use these virtual photons after falling into the hole to communicate with you outside the hole; nor could I escape from the hole by somehow turning myself into virtual particles. The reason is that virtual particles don't carry any information outside the light cone. See the physics FAQ on virtual particles for details.

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http://www.einstein-online.info/spotlights/changing_places
How BH can influence the orbital dynamics of stars in the vicinity but outside EH ?

Just another example of your dishonesty and not wanting to see the truth

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http://www.cco.caltech.edu/~kip/ftp/ScheelThorneUFN130110.pdf

Geometrodynamics: The Nonlinear Dynamics of Curved Spacetime:

ABSTRACT:
We review discoveries in the nonlinear dynamics of curved spacetime, largely made possible by numerical solutions of Einsteinâ€™s equations. We discuss critical phenomena and self-similarity in gravitational collapse, the behavior of spacetime curvature near singularities, the instability of black strings in 5 spacetime dimensions, and the collision of four-dimensional black holes. We also discuss the prospects for further discoveries in geometrodynamics via observation of gravitational waves

21. ### RajeshTrivediValued Senior Member

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This fossil field theory has stable field configurations problems, which you will not understand....

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There is only one person that does not understand, and that has been proven by the many requests of our expert Professors for you to learn some GR.
You need to do better Rajesh.

23. ### RajeshTrivediValued Senior Member

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These are non exact numerical solutions which again you will not understand......due to non linearity of EFEs the superposition of spacetime distortion for multi-body is a GR problem area..