Does Time Flow Differently in Distant Galaxies Due to Speed?

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Discussion Overview

The discussion revolves around the concept of time flow in distant galaxies, particularly in relation to their speeds and the effects of time dilation as described by the theory of relativity. Participants explore the implications of these ideas on the perception of time across different frames of reference, as well as the distinctions between special relativity and cosmological models.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that if the Milky Way is traveling at speed X, then a galaxy traveling at speed 2X would experience time differently, proposing that 1 second in that galaxy might equate to 0.8 seconds from the Milky Way's perspective.
  • Another participant clarifies that time dilation is a relative effect observed when comparing different frames of reference, emphasizing that an observer in a distant galaxy would not experience time differently in their own frame.
  • A third participant reinforces the relativity of time, noting that clocks in other galaxies would appear to tick more slowly from our perspective, while observers in those galaxies would see our clocks ticking slower as well.
  • A later reply refines the initial claims by stating that the relationships described are not entirely aligned with special relativity due to the curvature of cosmological spacetime, which affects calculations based on the model used, specifically referencing the FRW model with lambda cdm parameters.
  • This participant also mentions that locally, light travels at the same speed for all observers and that clocks tick at the same rate absent gravitational differences.

Areas of Agreement / Disagreement

Participants express varying interpretations of time dilation and its implications across different galaxies. There is no consensus on the initial claims regarding time flow differences, and the discussion reflects multiple competing views on the relationship between speed, time, and the curvature of spacetime.

Contextual Notes

The discussion highlights limitations in understanding due to the complexity of cosmological models and the assumptions involved in comparing different frames of reference. The nuances of special relativity versus cosmological effects remain unresolved.

Wykydtron
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Ok if these two facts are true
1. The faster you go time slows down
2. The galaxies farther away are traveling faster
Does this mean the flow of time would be different in different galaxies?

Ill do my best to explain what I am thinking
If the milky way is traveling at a speed of X we see 1 second as 1 second
But in a galaxy traveling 2X would 1 second = something like 0.8 seconds because time is slower the faster you are going?
 
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I believe you are correct. I would like to make sure you understand that time dilation is simply an effect of transforming one frame of reference to another. A person traveling at 90% the speed of light relative to you and I would NOT experience time any differently in their own frame of reference. It is only when you compare two different frames that time dilation is observed.

Another thing; from our point of view the milky way is not moving in any direction and we are not experiencing any time dilation at all because of this, just like an observer would experience in their own galaxies.
 
Just to reinforce what Drakkith said, all of that's going to be relative. Any clocks in other galaxies which we can see will appear to be ticking more slowly than clocks with rest with respect to us, but any observers in that other galaxy will see our clocks ticking slower than theirs. Very odd, but welcome to Special Relativity.
 
Ok if these two facts are true
1. The faster you go time slows down
2. The galaxies farther away are traveling faster

more accurate to say:
1. The faster you go relative to someone else, the more your local time appears to slow to them.
2. more distant galaxies are separating faster than neaby galaxies.

The relationships you describe are not quite the same as special relativity because cosmological spacetime is curved while SR spacetime is flat. How you describe that curvature affects your calculated measures and is dependent on the model you use. The standard model used by cosmologists is the FRW model with lambda cdm parameters that make the general model a close fit to our universe.

A good reference from which to begin to think about cosmological comparisons from relativity are these ideas:

Locally, light travels the same speed for everybody: So light in a distant galaxy whizzes by local observers there at 'c', just like it does here locally for us.

Locally, everybody's clocks tick at the same rate [absent gravitational potential differences such as those near black holes].
 

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