Angular Velocity: Can a Body Move Faster Than C?

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Discussion Overview

The discussion revolves around the question of whether a body can appear to move faster than the speed of light (c) when observed from a rotating reference frame, specifically in the context of rotating one's head to observe distant objects in the night sky. The scope includes conceptual reasoning and implications of relativistic physics.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant claims that rotating their head at 1 rad/s allows them to see a body 350,000 km away moving faster than c.
  • Another participant questions the logic behind this claim, suggesting that what is observed is light emitted from the body 1.2 seconds earlier, thus not actually exceeding c.
  • Some participants reference an external thread discussing similar phenomena related to stars appearing to exceed c due to the Earth's rotation.
  • There is a reiteration of the idea that the speed of light is constant and invariant in inertial frames, with a rotating frame not being inertial.
  • One participant expresses confusion about the external thread and suggests there may be an issue with accessing it.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the interpretation of observations made from a rotating frame and whether these observations imply superluminal motion. The discussion remains unresolved with multiple competing views presented.

Contextual Notes

Participants highlight the importance of understanding the distinction between perceived motion and actual motion in the context of relativistic physics. The discussion also reflects on the limitations of observations made from non-inertial frames.

Sandeep T S
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When I rotate my head with 1rad/s , I can see a body which 350000km away have velocity greater than c.is that possible?
 
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By what logic will the body appear to have velocity greater than c? What you see is the light emitted by the body about 1.2 s earlier.
 
kuruman said:
By what logic will the body appear to have velocity greater than c? What you see is the light emitted by the body about 1.2 s earlier.
Just rotate head in night sky, you will see stars are rotating, v=r ×omega
 
Sandeep T S said:
When I rotate my head with 1rad/s , I can see a body which 350000km away have velocity greater than c.is that possible?
Have you tried turning your head at 1rad/s? Was it possible?

The speed of light is constant and invariant in inertial frames of reference. A rotating frame is not inertial.
 
Sandeep T S said:
I didn't got this, i think a problem with site
Please try again. That (long) thread should answer your questions about this thought experiment.

We spent a lot of electrons on that thread, so this duplicate of it is closed for now.
 

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