What happens when monochromatic light travels for eternity?

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Discussion Overview

The discussion revolves around the implications of a monochromatic light beam traveling indefinitely in space, exploring concepts such as energy dispersion, the nature of existence, and the relationship between time and dimensions. Participants engage with theoretical considerations regarding the fate of light in a finite universe and the philosophical implications of measurement and existence.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that a light beam will spread out over an infinite distance, leading to a reduction of its energy to zero over an infinite time, raising questions about the nature of time and existence.
  • There is a proposition that if something finite is spread over an infinite space, it ceases to exist, but the infinite time required for this process creates a paradox.
  • The concept of Planck lengths is introduced, questioning whether there is a minimum wavelength or amplitude beyond which light no longer exists.
  • A participant questions the implications of a light beam traveling into infinite emptiness, pondering whether it ceases to exist if it is never measured or interacts with anything.
  • The uncertainty principle is mentioned, suggesting that if a light beam cannot be measured for eternity, its existence may be called into question.
  • Several participants seek clarification on the original post, indicating confusion over the arguments presented and the structure of the questions posed.

Areas of Agreement / Disagreement

Participants express confusion and disagreement regarding the original claims and analogies presented. There is no consensus on the validity of the arguments or the conclusions drawn from them.

Contextual Notes

The discussion includes complex philosophical and theoretical considerations that are not fully resolved, with participants expressing varying levels of understanding and interpretation of the concepts involved.

jimmylegss
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So I shoot a light beam out in space of monochromatic light, it would spread out right? So over time it should spread out over a infinite distance? If we assume the universe is finite? And since the light beam has a finite amount of energy, that means it will be reduced to zero.

If this is so, and the universe dies a heat death, it would take an infinite amount of time for this to happen? Which means it will not happen? Because you would then be able to pinpoint the exact time on this infinity scale. And that is impossible. Because that would make it a finite amount of time again.

In other words really, the conclusion is, if you spread a finite thing out over an infinite space, it will stop existing. But it will take an infinite amount of time, so therefore it cannot happen. Because you will never reach that point. So something about the time dimension coming before the other dimensions?

Like counting from two to three in exponentially smaller steps. You never reach three, so as far as the counter is concerned three does not exist.

How do Planck lengths come into this? Since there seem to be minimum amounts in our universe that something can exist. So is there a minimum wave length or amplitude? Once it would go beyond that, it technically no longer exists?

Is there some implication that if a lightbeam would travel into infinite emptiness, it will never reach a destination? If it will never be measured again, or interact, does it even exist anymore? What about the uncertainty principle (where laws of physics can be temporarily broken). If there is nothing more to measure for an eternity, then a light beam stops existing? Since existence is basically the chance of interacting some point in the future? If that is reduced to zero, it stops existing?

My head hurts :/ .
 
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Is there a specific question in there?
 
Where do I get it wrong?
 
jimmylegss said:
Where do I get it wrong?
"You never reach three, so as far as the counter is concerned three does not exist." Right, but you are using that to (to extend the analogy) conclude that three does not exist at all, which is silly.
 
By the counter I mean the entity counting from two to three in exp smaller steps. Because if you add in a counter in that context plus element of time, three does not exist.
 
Jimmy, I can't begin to make heads or tails of your post. I recommend starting with a single question and not chaining together answers to your own questions to make other questions. Thread locked.
 

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