What happens when monochromatic light travels for eternity?

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Monochromatic light, when emitted into space, spreads out over infinite distances, leading to a reduction in energy until it theoretically reaches zero. This raises the paradox of whether it can truly reach this state given that it would require an infinite amount of time, suggesting it may never cease to exist. The discussion also touches on the implications of Planck lengths and the uncertainty principle, questioning if a light beam loses existence if it travels indefinitely without interaction. The complexity of the argument leads to confusion, prompting the suggestion to focus on a single question for clarity. Ultimately, the conversation highlights the philosophical and physical implications of light, time, and existence in an infinite universe.
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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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