What are the implications of rotational reference frames?

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Discussion Overview

The discussion centers on the implications of using rotational reference frames in physics, particularly in relation to the movement and position of objects. Participants explore the conceptual framework of rotational versus inertial frames, the effects of fictitious forces, and the nature of motion in these contexts.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests that viewing the Earth as stationary with the universe rotating around it leads to interesting implications, including the appearance of non-rotating objects moving faster than the speed of light.
  • Another participant clarifies that the term "rotating reference frame" specifically refers to a body spinning about its own axis, distinguishing it from orbital motion.
  • A participant argues that the reference frame of an orbiting body can still be considered rotational, maintaining that the questions regarding rotation and its implications remain valid.
  • There is a mention of fictitious forces, such as the Coriolis force, which arise in rotating reference frames and affect the motion of objects in curved paths.

Areas of Agreement / Disagreement

Participants express differing views on the nature of rotational reference frames and their implications. While some agree on the existence of fictitious forces, there is no consensus on the interpretation of rotational frames versus inertial frames or the validity of the initial claims regarding motion and speed.

Contextual Notes

Participants highlight the potential confusion between rotational and orbital motion, indicating a need for clarity in definitions. The discussion also touches on the limitations of applying concepts from one frame to another without addressing the underlying physics.

CaptainQuasar
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It occurred to me that, as far as calculating the position or movement of objects a reference frame can be rotational, see the http://en.wikipedia.org/wiki/Rotating_reference_frame" . So instead of seeing the Earth as orbiting the sun you could say that the Earth is stationary and the rest of the universe is rotating around an axis going through the sun and perpendictular to the plane of the Earth's orbit. (I feel dizzy…)

Of course, this results in all sorts of http://en.wikipedia.org/wiki/Fictitious_force" . It also seems notable to me that this will also mean that non-rotating objects a certain distance from the axis will appear to be moving faster than c. And accelerating at a ridiculous rate, of course.

I was wondering if anything interesting is derived from the fact that any object can be construed as rotating at any rate by selecting a different rotational reference frame. And also if anything interesting happens as the speed of rotation approaches the speed of light with respect to a non-rotating reference frame. (Not physically possible with any known material, of course, but you get what I mean.)

It seems that this relativity of rotation can't be "real" in that there's only one reference frame where conservation of momentum, conservation of energy, etc. aren't violated. (Or is there a Lorentz-transformation-like way of correcting for that?) So does that mean that even though the universe doesn't have a "here" and a "there" (i.e. no absolute inertial reference frame) it does have an "up" and a "down", left and right, forwards and backwards? (Obviously these are anthropomorphic labels but the point is that cardinal directions are the same somehow everywhere and everywhen and in every inertial reference frame.)
 
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In talking about orbits you have the wrong concept in mind for a rotating reference frame. The motion that occurs when one body orbiting another body is not rotation; its an orbit. A rotating body is spinning about some axis located within the body. The reason the surface of the Earth is called a rotating reference frame is because the Earth is rotating about its own axis (which is why our days are only 24 hours long).
 
D H said:
A rotating body is spinning about some axis located within the body.

Uh, thanks. But the reference frame that an orbiting body would be stationary in would still be a rotational one - I'm talking about a reference frame rotating, not an object - and the various questions above still apply.
 
Maybe what confused you is that the phantom forces in the situation I describe aren't things like centrifugal force but are things like the Corolis force, with other objects in the universe accelerating along curved paths. Look at the animation on the right in http://en.wikipedia.org/wiki/Coriolis_force" .
 
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