Can I Push the Moon Instantly?

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    Moon Push
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Discussion Overview

The discussion revolves around the hypothetical scenario of pushing the Moon using a stick that extends from Earth to the Moon. Participants explore the implications of such a push in relation to the speed of light and the transmission of force through the stick.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions whether a push could be faster than light, proposing a scenario where a stick could defy physics to push the Moon instantly.
  • Another participant suggests that pushing one end of the stick would necessitate movement at the other end, implying a potential for instantaneous action.
  • A different viewpoint argues that while the 'poke' may seem to travel faster than light, the actual movement of the stick would be slower than light, thus not violating any physical laws.
  • Concerns are raised about the nature of the push, with one participant asserting that the push must react instantly, questioning how one end of the stick could move while the other does not.
  • One participant references a previous discussion to support their points.
  • Another participant clarifies that the impulse travels at the speed of sound within the rod, which is slower than light, and emphasizes that the movement of a laser dot does not carry information across distances, allowing it to appear to move faster than light.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the push and the implications of speed limits in physics. There is no consensus on whether the push could be instantaneous or if it adheres to the constraints of relativity.

Contextual Notes

Participants rely on hypothetical scenarios and assumptions about the properties of the stick and the nature of force transmission, which remain unresolved. The discussion also touches on the distinction between apparent motion and information transfer.

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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