2cars moving slightly less than speed of light look faster than light to each other?

In summary, according to the principle of relativity, the speed of light remains constant regardless of the speed of the observer. This means that even if two cars are moving towards each other at high speeds, they will still see light moving away from each other at the same speed. This can be derived from the velocity-addition formula in special relativity.
  • #1
AgentPancake
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if the cars are moving towards each other.
 
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  • #2


AgentPancake said:
if the cars are moving towards each other.
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*.



(*) 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.
 
  • #4


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?
 
  • #5


This phenomenon is known as the "relativity of simultaneity," which is a fundamental principle of Einstein's theory of special relativity. According to this principle, the perception of time and space is relative to the observer's frame of reference. In this case, the cars are moving towards each other at a high speed, which causes their perception of time and space to be distorted. This distortion can make it appear as though the cars are moving faster than the speed of light relative to each other. However, from an outside observer's perspective, the cars would still be moving at a speed slightly less than the speed of light. This is due to the fact that the speed of light is the maximum speed at which any object can travel in the universe. Therefore, while the cars may appear to be moving faster than light to each other, they are still bound by the laws of physics and cannot actually exceed the speed of light.
 

1. How is it possible for two cars moving at slightly less than the speed of light to appear faster than light to each other?

According to Einstein's theory of relativity, time and space are relative and depend on the observer's frame of reference. This means that the perceived speed of an object can be affected by the observer's motion. In the case of two cars moving at nearly the speed of light, they would each perceive the other car as moving faster than light due to their relative velocities.

2. Does this mean that the cars are actually moving faster than light?

No, the cars are not actually moving faster than light. According to the theory of relativity, nothing can travel faster than the speed of light in a vacuum. The apparent speed of the cars is a result of the observer's frame of reference and does not violate the laws of physics.

3. How does the theory of relativity explain this phenomenon?

The theory of relativity states that the laws of physics are the same for all observers, regardless of their relative motion. This means that the perceived speed of an object can vary depending on the observer's frame of reference. In the case of two cars moving at nearly the speed of light, each car would perceive the other as moving faster than light due to their relative velocities.

4. Can this phenomenon only occur with cars or can it happen with any object?

This phenomenon can occur with any object, as long as it is traveling at close to the speed of light. The perceived speed of an object will always be affected by the observer's frame of reference, regardless of what type of object it is.

5. Are there any other implications of this phenomenon?

Yes, this phenomenon has important implications for our understanding of time and space. It shows that the perception of time and distance is relative and can vary depending on the observer's frame of reference. This has been confirmed through experiments such as the famous twin paradox, where one twin who travels at high speeds ages slower than the twin who stays on Earth.

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