Speed of Light Thought Experiment

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Discussion Overview

The discussion revolves around a thought experiment concerning the speed of light and the possibility of faster-than-light information transmission using a hypothetical setup involving a long tube filled with snooker balls. The scope includes conceptual exploration and theoretical implications of the speed of light in relation to mechanical systems.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant proposes a scenario where a signal is transmitted faster than light by pushing a snooker ball through a long tube, suggesting that the signal travels 600,000 km in one second.
  • Another participant questions the validity of the thought experiment by asking about the speed of sound in snooker balls, implying that the transmission of the signal may not be as instantaneous as claimed.
  • A third participant references a related discussion on the Physics Forums regarding the transmission of signals faster than light, indicating that this is a common misconception.
  • Another participant acknowledges the creativity of the thought experiment while suggesting that it may be based on a misunderstanding of physical principles.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as there are competing views regarding the feasibility of the proposed thought experiment and the implications of the speed of light.

Contextual Notes

The discussion does not resolve the assumptions regarding the physical properties of the snooker balls or the nature of signal transmission in this hypothetical scenario.

Jopus Foghlu
A thought experiment about the speed of light. Say I build a 600,000 km long tube around the circumference of the Earth at the Equator. The tube's inner diameter is constant at 54.4505 mm. A snooker ball is perfectly manufactured to its lowest tolerance by a special new machine. Each one is 54.4501 mm in diameter. I fill said tube with snooker balls (btw the tube wraps around Earth's circumference at the Equator approximately 25 times, so there are approximately 11,440,000,000 of them. I have assumed light travels 300,000 km every second. I am also in possession of a super powerful pushing arm with Giga-tonnes of pushing power, which is needed even though the tube is frictionless due to the sheer number of snooker balls it needs to displace. 25 diameters up from where I start pushing, a ball pops out in 1 second. The 'signal' necessary for it to do so has just traveled 600,000 km in one second. Yet light can only travel half that distance in the same time. Voila! Faster than light information transmission. Okay, what am I missing if anything?
 
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Jopus Foghlu said:
Okay, what am I missing if anything?

Yes you are missing something. What is the speed of sound in snooker balls?

Welcome to the PF, BTW. :smile:
 
Last edited:
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Likes   Reactions: tech99 and rootone
@Jopus Foghlu don't feel bad. We've had probably several hundred people come here and ask that so you're not alone in your misconception.
 

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