Can I Push the Moon Instantly?

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SUMMARY

The discussion centers on the concept of whether pushing the moon using a hypothetical stick could result in instantaneous movement. Participants clarify that while the idea of a stick transmitting a push faster than light seems plausible, it contradicts established physics. The impulse generated by the push travels at the speed of sound within the stick, which is slower than light. Additionally, the analogy of a laser pointer moving faster than light is addressed, emphasizing that while the dot appears to move quickly, it does not convey information across distances.

PREREQUISITES
  • Understanding of basic physics principles, particularly the speed of light and sound.
  • Familiarity with the concept of information transfer in physics.
  • Knowledge of the limitations of physical materials, such as sticks or rods, in transmitting forces.
  • Awareness of optical phenomena, such as the behavior of laser pointers.
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  • Research the principles of wave propagation in solid materials.
  • Study Einstein's theory of relativity and its implications on speed limits in physics.
  • Explore the concept of information transfer and its constraints in physics.
  • Investigate the physics of light and how it interacts with different mediums.
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Physics enthusiasts, educators, and students interested in understanding the limitations of physical interactions and the principles governing speed and information transfer in the universe.

darrin016
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Can a push, be faster than light?
If I was to hold a stick that stretched out to the moon, and pushed it. Could I push the moon instantly?
Seeing as that the stick could defy physics etc and I had enough strength to make an impact on the moon.
 
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I feel like it's possible. I push one end, the other end needs to move to make room for the stick pushing right?
 
Even though the 'poke' is 'travelling' faster than light, as long as the stick is traveling slower than light, you're okay. If you had a million billion trillion km long stick that you pushed 1mm in 1/100th of a second, nothing would actually be going faster than light. The same idea applies with a laser pointer on the moon. If you flick the dot back and forth really fast on earth, the dot appears to move faster than light.
 
But the push would have to react instantly. How can one end of the stick move, while the end doesn't?
Has to be faster than light
 
See https://www.physicsforums.com/showthread.php?t=536289
 
Last edited by a moderator:
97313 said:
Even though the 'poke' is 'travelling' faster than light,
It is not. The impulse is traveling at the speed of sound within the rod, which is slower than light. The impulse carries information so it cannot travel faster than light.

97313 said:
The same idea applies with a laser pointer on the moon.
No, it is completely different.

97313 said:
If you flick the dot back and forth really fast on earth, the dot appears to move faster than light.
It doesn't just appear, it is moving faster than light. But the dot carries no information across the surface, so it can move at any speed.
 

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