The opposite of the limit of light

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Discussion Overview

The discussion revolves around the implications of the theory of relativity, particularly focusing on time dilation, the perception of speed, and the concept of stationary objects in different reference frames. Participants explore how these concepts relate to the speed of light and energy conservation during movement.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants propose that as speed increases, time slows down and distance decreases, suggesting that at the speed of light, time and distance approach zero.
  • Others argue that the time dilation factor (gamma) is dependent on the absolute value of velocity in an inertial frame, implying that all observed clocks run slow regardless of their direction.
  • A participant questions whether their own clock is always the fastest, leading to a discussion about being stationary in one's own frame.
  • There is a suggestion that the speed limit of light applies only to other objects, as one’s own speed is always perceived as zero in their own frame.
  • Some participants express confusion about the relationship between energy and movement, particularly regarding the fate of energy when thrust is applied without apparent movement.
  • It is noted that energy conservation requires careful consideration in non-inertial frames, with energy being transferred to the kinetic energy of exhaust gases during thrust.
  • Another participant highlights that while one can measure speed relative to other objects, achieving a frame moving away from another at the speed of light is impossible.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement on various points, particularly regarding the implications of being stationary in one's own frame and the application of the speed limit of light. The discussion remains unresolved on several aspects, particularly concerning energy and movement.

Contextual Notes

Limitations include the dependence on definitions of inertial and non-inertial frames, as well as unresolved questions about energy conservation in different frames of reference.

Slait
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I was thinking about the theory of relativity and how the faster we go the slower time goes and the smaller we become which evens out the equation for speed.

Distance / Time = speed

Correct me if I am wrong but what i see from this is, as we go faster time slows down and distance decreases which keeps the speed of light at a constant to the person in motion. So 1 second in the equation becomes, .9 seconds as we go faster. And as we get up to the speed of light, time becomes 0 and the distance is 0 in the equation. So using this can't we go the other way, and go slower to the point that 1 second is longer and our distance is larger? Maybe even calculate what a truly stationary object would be?
 
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Slait said:
I was thinking about the theory of relativity and how the faster we go the slower time goes and the smaller we become which evens out the equation for speed.

Distance / Time = speed

Correct me if I am wrong but what i see from this is, as we go faster time slows down and distance decreases which keeps the speed of light at a constant to the person in motion. So 1 second in the equation becomes, .9 seconds as we go faster. And as we get up to the speed of light, time becomes 0 and the distance is 0 in the equation. So using this can't we go the other way, and go slower to the point that 1 second is longer and our distance is larger? Maybe even calculate what a truly stationary object would be?

No because the time dilation factor (gamma) is dependent on the absolute value of the velocity in our (inertial) frame. It doesn't matter which direction the clocks we are observing are traveling we will still observe them to run slow.
 
So our clock will always be the fastest? everything else that we observe will be slower? Wouldnt that make us stationary?
 
Slait said:
Wouldnt that make us stationary?
In our frame, yes, by definition.
 
So if we are always the slowest moving object from our own frame, wouldn't that mean the speed limit of light only applys to other objects? because no matter how fast we are moving we are always at 0 in comparison to the speed of light.
 
Slait said:
So if we are always the slowest moving object from our own frame, wouldn't that mean the speed limit of light only applys to other objects? because no matter how fast we are moving we are always at 0 in comparison to the speed of light.
Yes. What? Yes.

How does the middle statement, follow from the first and last statements? (inasmuch as a preceding statement can follow a following statement, if you get my meaning...)

Do you mean why can't we travel at the speed of light?

Well, even if we were traveling at .99999999999999999c, we'd still be stationary in our own frame, so it's not like our being stationary in our own frame is preventing us from traveling at c.

Remember, we can only measure our speed wrt other objects. The trick really is to get our frame moving away from some other frame, such that that other frame is moving away from us at the speed of light. And that we can't do.
 
That just blows my mind.

Im having trouble putting this and the energy of movement together now. If we arent moving, no matter how much thrust we put into trying to move us, where does that energy go?
 
Slait said:
wouldnt that mean the speed limit of light only applys to other objects?
In our reference frame, yes. Of course the speed of light limit applies to us in other reference frames.
 
Slait said:
Im having trouble putting this and the energy of movement together now. If we arent moving, no matter how much thrust we put into trying to move us, where does that energy go?
In this case your frame is not an inertial frame so things like energy conservation require a bit more care. However, essentially the energy goes into the kinetic energy of the exhaust gasses.
 
  • #10
Slait said:
That just blows my mind.

Im having trouble putting this and the energy of movement together now. If we arent moving, no matter how much thrust we put into trying to move us, where does that energy go?
If you are using thrust to accelerate, then in any given inertial frame, your speed is changing. Of course if your speed is changing in every inertial frame, then the definition of which frame qualifies as your "inertial rest frame" is changing over time.
 

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