Will a Toy Top Keep Spinning in Space?

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SUMMARY

A toy top spun in the vacuum of space will continue to spin indefinitely due to the conservation of angular momentum, provided it remains in a closed system without external interactions. The discussion references the Einstein Probe B experiment, which utilized highly precise gyroscopes to measure spacetime curvature, demonstrating that even in non-closed systems, the effects of external forces can be minimal. Gravitational radiation may cause a very slow decrease in spin for tops with non-zero quadrupole mass distributions, but this effect is negligible for a typical toy top.

PREREQUISITES
  • Understanding of angular momentum conservation
  • Familiarity with general relativity (GR)
  • Knowledge of gravitational radiation and its effects
  • Basic principles of gyroscopic motion
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  • Research the Einstein Probe B experiment and its implications for gyroscopic measurements
  • Study the principles of angular momentum in closed systems
  • Explore the effects of gravitational radiation on rotating bodies
  • Learn about gyroscopes and their applications in measuring spacetime curvature
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Physics students, aerospace engineers, and anyone interested in the principles of motion and general relativity will benefit from this discussion.

l0rca
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Sorry if this is the wrong forum. I looked in the FAQ, but since this isn't a homework question and doesn't fit the syntax of asking it, I thought here was the best place.

If I started spinning a toy top in dead space, would the top ever stop spinning?

My first guess is 'yes, it will stop,' because the motion of the top is accelerative, and in order to keep spinning must continue to accelerate in more than one direction. However, I'm not sure if I remember enough of GR to figure out where the initial energy of spinning the top ends up (or if this question is a sort of fallacy in this situation), and I did a google search before coming here where there was supposedly an experiment carried out like this to prove that the top does keep spinning.

Any help here?
 
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Angular momentum is conserved, so it is only interactions with other material or releasing radiation that could make the top stop spinning. (ie. if it is a closed system, the system can't loose angular momentum)

Since you asked for an experimental example, the first thing that came to mind is the Einstein Probe B experiment which had some of the most precise gyroscopes ever built. These are basically spinning tops. The rate of the spinning was constant enough to allow measurement of some subtle features of the curvature of spacetime around the Earth (despite even some slight interactions due to our requirement that we need it to be a non-closed system so we can measure it, and uncontrollable interactions due just to other material enclosing the device).

Since you mentioned GR, you may also be thinking about gravitational radiation. While it would take an incredibly long time for this to affect just a toy top, if the top has a non-zero quadrapole or higher order mass distribution, it will radiate gravitational waves and very very slowly slow down.
 
So, even though the top is accelerating, so long as the acceleration is purely in terms of velocity, it does not require continued energy to stop accelerating?
 

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