- #1
AgentPancake
- 9
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if the cars are moving towards each other.
Last edited:
Do Cars Moving Near Light Speed Appear Faster to Each Other?
- Context: Undergrad
- Thread starter AgentPancake
- Start date
Click For Summary
Discussion Overview
The discussion revolves around the behavior of cars (or spaceships) moving at relativistic speeds, particularly whether they appear to move faster relative to each other when approaching at high velocities. The scope includes theoretical considerations from the principles of special relativity and the implications of light speed constancy.
Discussion Character
- Exploratory, Technical explanation, Debate/contested
Main Points Raised
- Some participants suggest that if two cars are moving towards each other, their relative speeds may not be as intuitive as one might expect due to the principles of relativity.
- One participant asserts that the speed of light remains constant regardless of the motion of the observer, referencing the principle of relativity.
- A participant provides a link to the velocity addition formula in special relativity, indicating its relevance to the discussion.
- Another participant presents a scenario involving a spaceship moving at 0.9c and questions their understanding of how light from the spaceship would reach an observer, suggesting a need for clarification on the implications of this model.
Areas of Agreement / Disagreement
Participants express differing views on the implications of relativistic speeds and the constancy of light speed, indicating that multiple competing perspectives remain without a clear consensus.
Contextual Notes
The discussion includes assumptions about the behavior of light and relative motion that may not be fully articulated, and the implications of the velocity addition formula are not resolved within the conversation.
- #2
Hootenanny
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No. The speed of light doesn't change no matter how fast you are moving. Light will always move away (toward) you at the same speed, c. This is a consequence of principle of relativity*.AgentPancake said:
(*) Often people will say that this is a postulate of special relativity. However, it is possible to derive the constancy of the speed of light simple from the principle of relativity.
- #3
tiny-tim
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- #4
jewbinson
- 127
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Interesting.
So suppose your friend's spaceship is moving towards you at 0.9c.
Then after 1 second he would have moved 0.9C and the light from 1 seconds ago will be 0.1C infront of where he is now. When the light reaches you, your friend would have moved closer to you, but still I can't (immediately) see how any rules can be broken by this model.
Anyway, is my understanding correct?
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