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What happens to the spacetime interval between two events as they approach a BH?
ie how does the r/t ratio in the s^2= ct^2-r^2 formula change?
Reedit: the event pairs are causally connected.
That shouldn't change at all. It's frame invariant, so it is the same in any coordinate system of choice.
Quote from: Halc on 19/02/2021 17:28:56It's frame invariant, so it is the same in any coordinate system of choice.I am talking about similar pairs of events ( say a ball striking a surface ,event#1 and rebounding and striking another surface I metre distant,event#2)From the frame of a distant observer there is a spacetime interval between those two events.
It's frame invariant, so it is the same in any coordinate system of choice.
If we repeat the experiment closer to BH
then I am asking how the new spacetime interval compares to the earlier spacetime interval ( and how the r/t ratio developes as the experiments are made closer to the BH(or any gravitational source)
Then they're a different pair of events.
Depends on how long it is between strikes as measured by the ball. If it's the same time, then the interval is the same. The two events could be on either side of the event horizon if you please. It really doesn't make a difference, except in the latter case, the outside observer isn't going to observe both events.
If the spacetime interval doesn't change does the spatial component change wrt the temporal component?
The spatial and temporal coordinates of any pair of events is coordinate system dependent, so yes, both change with a change in coordinate system (observer frame if you will).
So ,in my scenario as similar (=identical in their own frame ) pairs of events are recorded by an outside observer does the ratio of the temporal to the spatial component of the (same) spacetime interval change as the subsequent event pairs are observed nearer the source of gravity ?And ,if so which component increases wrt to the other?
Since ,I have heard the time slows from the outside observer's perspective as object's approach an event horizon can I guess it to be the temporal component that increases wrt the spatial component?
the ratio of temporal to spatial is going to go from infinite (T / 0) to something finite (>T / >0). This is all true anywhere, so no mention of the black hole is needed.
Again, the interval is frame invariant
So it makes no difference whether the ball is in a region of flat space or curved space?
What about if there is a region of curved space between the observer and the ball ?(which is still falling into its own gravity well.
Quote from: geordief on 20/02/2021 04:37:52So it makes no difference whether the ball is in a region of flat space or curved space?ExactlyQuoteWhat about if there is a region of curved space between the observer and the ball ?(which is still falling into its own gravity well.Yet again, it is frame invariant, and thus not observer dependent.
Is it fair or noteworthy to say all these events in GR are treated as point objects even though they are actually spatio-temporally extensive?
Is that where a theory of quantum gravity might be useful?