Communication with no time boundaries?

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Discussion Overview

The discussion revolves around the concept of instantaneous communication through a hypothetical perfectly rigid pole extending from the Moon to the Earth, exploring implications related to Special Relativity and the nature of information and matter.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that if perfectly rigid poles existed, information could be transmitted instantly, but this is challenged by the principles of Special Relativity.
  • Others argue that Special Relativity forbids perfectly rigid bodies because it would violate the postulate that information cannot travel faster than the speed of light.
  • A participant questions how Special Relativity specifically forbids perfectly rigid bodies, prompting further discussion on the nature of forces and vibrations in materials.
  • It is suggested that electromagnetic forces hold molecules together, and any vibration transmitted through a material cannot exceed the speed of light, with actual speeds being much lower.
  • Some participants differentiate between information and matter, with one asserting that while matter moves, it is the communication between particles that is crucial.
  • A later reply discusses the relationship between information and matter, referencing new views that suggest information may be a fundamental constituent of matter and energy.
  • Historical context is provided, noting that prior to Einstein, time and space were viewed as separate entities, and the relationship between them was not understood.

Areas of Agreement / Disagreement

Participants express differing views on the nature of information and matter, the implications of Special Relativity, and the concept of rigid bodies. No consensus is reached on these points.

Contextual Notes

The discussion includes assumptions about the nature of rigidity and the speed of information transfer, which are not universally accepted. The implications of Special Relativity and the definitions of information and matter remain unresolved.

wrekced
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Assuming a perfectly rigid pole stretching from the Moon to the Earth. Wouldn't pushing on one end be felt instantly at the other?
 
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wrekced said:
Assuming a perfectly rigid pole stretching from the Moon to the Earth. Wouldn't pushing on one end be felt instantly at the other?
If perfectly rigid poles exists, then yes information could be transmitted instantly. However, perfectly rigid bodies are forbidden by Special Relativity.
 
Hootenanny said:
If perfectly rigid poles exists, then yes information could be transmitted instantly. However, perfectly rigid bodies are forbidden by Special Relativity.

Hmmm. Thanks! How in particular does Special Relativity forbid perfectly rigid bodies?
 
wrekced said:
Hmmm. Thanks! How in particular does Special Relativity forbid perfectly rigid bodies?
SR forbids perfectly rigid bodies precisely because it violates the postulate that information cannot be transmitted faster than the speed of light.
 
Information and matter are two different things. In a sense matter isn't moving anywhere. Its the communication between each particle?
 
wrekced said:
Hmmm. Thanks! How in particular does Special Relativity forbid perfectly rigid bodies?

What do you think holds the molecules in a material together? Electromagnetic forces, which is governed by SR. When you transmit any vibration in a material, that vibration is being transferred via such EM forces. So it cannot be faster than c. In fact, it is quite a bit slower because the molecules/atoms have masses.

Zz.
 
Aethelwulf said:
Information and matter are two different things. In a sense matter isn't moving anywhere. Its the communication between each particle?
Information and matter are indeed two different things, but matter does move in this case. If you apply a force to a rod - it moves.
 
If you push one end of the pole of length L the other end won't start to move until a time t=c/L later,where c is the speed of sound; which is much, much lower than the speed of light . Hence, it is not a very efficient way of transfering information.

Example: the speed of sound in e.g. steel is about 4500 m/s, meaning if you push one end of a 1 km long steel pole the other end won't start to move until 1000/4500=0.2 seconds later.
 
Information and matter are two different things.

Says who? Oh how naive we are..."we know much, we understand little."

New views of the universe as a quantum computer say information is the basic constituent of matter and energy...and anyway, information theory can be viewed as a more general theory of entropy...as usual, everything is linked in mysterious ways we so often fail to discern.

Before Einstein, time and space were thought to be fixed, different, unrelated entities...having little if anything to do with gravity...people would have laughed at the thought they are so intimately related before Einstein's insights.

As nature increases entropy over time it also dissipates information...see DECODING THE UNIVERSE, Charles, Seife...also some views in Wikipedia...
 

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