Gravitational Time Dilation and Contradicting Physical Events

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Discussion Overview

The discussion revolves around a thought experiment involving gravitational time dilation as observed from a distance, specifically in the context of a baseball game occurring near a black hole. Participants explore the implications of time dilation on the perception of physical events and the resulting discrepancies in physics calculations.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant describes a scenario where an observer far from a black hole perceives events in a baseball game occurring in slow motion due to gravitational time dilation, raising questions about the consistency of physics in this context.
  • Another participant suggests that the observer could conclude the game is either on a rapidly receding stadium or in a deep gravitational field, noting that nonuniformity in time dilation would indicate the latter.
  • A further response emphasizes that observing the game for an extended period would reveal differences between a receding stadium and one in a gravitational field, as the former would appear to shrink while the latter would not.
  • Some participants express confusion about how the previous points address the original questions, indicating a lack of clarity in the responses provided.
  • One participant points out that the scenario is not exclusive to gravity, suggesting that similar effects would arise from special relativity if the stadium were receding at high speed, implying a need to clarify understanding of special relativity before addressing gravitational effects.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the clarity of the responses to the original questions. There are competing views on the implications of the thought experiment and the relationship between gravitational and special relativity.

Contextual Notes

Some assumptions about the nature of time dilation and the effects of gravity versus relative motion remain unresolved. The discussion highlights the complexity of distinguishing between gravitational effects and those arising from relative motion in special relativity.

timetravel_0
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Thought experiment:

Say for instance that a Baseball game is being played out on a planet that is orbiting the outer edge of a black hole. You, from deep in space away from any gravitational source, are watching this game from a powerful telescope. The batter comes up to bat; the pitcher throws the ball; the batter hits! The ball sources into center field, up and over the wall. It’s a home run!

Well, as the observer in space - time, relative to the baseball game near the black hole, is going much faster than it is for the players on the field. The players witness as the ball soars over their heads and into the stand. Nothing seems strange to them - but as the observer in space - you witness everything occurring in slow motion. Being that everything is slowed, the ball being hit soars slower, the swing of the bat is slower. If you were to calculate the mass of the bat, the mass of the ball, the velocity of the bat and the projected path of the ball - it wouldn't line up.

Similarly - if you were to attempt to reenact the event with the same size bat and ball and the same swing flowing as you observed in slow motion - you would slowly swing, and miss the ball, because it dropped before it reached home plate. But say for instance you did hit the ball with a slow swing it wouldn't go but a few feet - not many yards and over the fence as you had observed in the game.

The Physics doesn't line up.

My question is: 1. Am I thinking of this observation correctly (excluding the obvious gravitational pull of the black hole and its physical effect)? and 2. If this is a "correct" way of thinking - why does the physics not line up?

Thanks.
 
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The observer would conclude that the game is either taking place on a rapidly receding stadium, or in a deep gravitational field. To conclude the latter, he'd have to see some nonuniformity in the time dilation.
 
Bill_K said:
The observer would conclude that the game is either taking place on a rapidly receding stadium, or in a deep gravitational field. To conclude the latter, he'd have to see some nonuniformity in the time dilation.

Another way to distinguish is to watch for 'a while'. The receding stadium would visually get smaller, the stadium in deep gravity well would not.
 
I don't understand how any of that answered my questions. Maybe I'm missing both of your points.
 
timetravel_0 said:
I don't understand how any of that answered my questions. Maybe I'm missing both of your points.

One point is that your question is not specific to gravity or general relativity. The exact same scenario would occur if the stadium was receding from you at great speed, purely due to special relativity. If you can see this, then think whether you have a problem understanding special relativity. Confusion should be easier to clear up in this context before worrying about gravity.
 

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