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Just theoretically, when I turn on the lights in my super fast speed of light car, would I see the road if the light can't go faster than my car?

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  • $\begingroup$ The answer depends entirely on what Universe you manage to find such a car in. $\endgroup$
    – WillO
    Feb 12, 2022 at 17:05
  • $\begingroup$ The Universe where those speeds are considered average, lets say. :) $\endgroup$
    – knm
    Feb 12, 2022 at 17:13
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    $\begingroup$ Are you saying there's only one such possible universe? I can think of several off the top of my head, all with different laws of physics and different answers to your question. $\endgroup$
    – WillO
    Feb 12, 2022 at 17:37
  • $\begingroup$ As fast as light is impossible for an object with non-zero mass so your question is meaningless. $\endgroup$ Feb 13, 2022 at 3:59

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You won't see the road without your car lights turned on. But if you turned them on you could still see the road. Light always has the same speed, however fast you go. In your car frame, it goes at c always in all directions. So it hits the road in front of you and makes it way back to your eyes. The clocks on the road all go slower though. Almost standing still if you approximate c wrt to the road. The reflected light might have a different wavelength though. It depends if your eyes can see it but it's always better ti turn in your lights at night while cruising the roads at c, in the dark. If only for the other travelers...

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  • $\begingroup$ So the light would go faster than me in my car? Can it be compared to this famous question about a person walking in the train which goes 100km/h , what would be the walking speed of the person? $\endgroup$
    – knm
    Feb 12, 2022 at 17:12
  • $\begingroup$ @knm It would travel at c from your passengers seat and it would travel at c for me beside the road night picknicking. $\endgroup$ Feb 12, 2022 at 17:38

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