Can Light Waves Inside an Air-Tight Box be Reduced to Zero?

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Discussion Overview

The discussion centers around the question of whether light waves inside an air-tight box can be reduced to absolute zero, considering various types of light across the electromagnetic spectrum. Participants explore the implications of sealing light within a wooden box and the potential for light to dissipate over time.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions if light waves can dissipate to zero in a sealed box made of wood, suggesting that visible light will eventually deplete but may leave some spontaneous photon formation.
  • Another participant proposes that using mirrors inside the box might help retain light, but expresses skepticism about the feasibility of sealing the box effectively before light escapes.
  • A participant clarifies that the entire light spectrum, including x-rays and gamma rays, will still be present when the box is sealed, but questions whether the amplitude of those waves can ever reach zero.
  • It is noted that high-frequency electromagnetic waves will not be significantly affected by the wooden walls, while low-frequency waves may also pass through.
  • One participant speculates on the behavior of visible light in the box, suggesting it may dissipate asymptotically or bounce around indefinitely, depending on various factors related to absorption and emission.

Areas of Agreement / Disagreement

Participants express differing views on the behavior of light in the box, with no consensus reached on whether light can be completely reduced to zero. Some agree that certain wavelengths will not be contained, while others speculate on the potential for visible light to diminish over time.

Contextual Notes

Participants acknowledge that the discussion involves assumptions about the properties of materials and the nature of light, but these assumptions remain unresolved. There is also uncertainty regarding the effectiveness of the box in containing various wavelengths of light.

xcrunner2414
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If I built a box out of 2 inch thick wood, and made it air tight, would the light waves inside the box eventually dissipate and become absolutely zero? (meaning absolutely no light whatsoever)?
 
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Welcome to PF, Xcrunner.
It depends upon how you define 'light'. Anything within the visible spectrum will eventually be depleted, although there might be some tiny spontaneous photon formation. The wood itself will emit infrared based upon its temperature, and higher frequencies such as X-rays won't be blocked.
That's all that I've got; best wait for someone else to provide a better response.
 
Hmm. Interesting. I wonder if you put mirrors on the inside surfaces, if you could catch the light and keep it in case the lights go out.

Seriously, though, I'm not sure you could close the box before most of the light got out anyway. Light's sort of a slippery substance. Everything Danger said is true, but... I doubt that you'd catch *any* light to begin with, whether it dissipated or not. Particularly not with 2 inch thick wood... even if it were "air tight".
 
Well, unless you sealed it off completely and then had some way to light a match inside or something. Hmm. Who knows? Hopefully you'll get a more informed answer from somebody else...
 
I don't mean visible light. I mean the entire light spectrum... x-rays, gamma rays, visible light, infrared, microwaves, etc. all of them as waves. Obviously there are still those waves when I seal up the box, but will the amplitude of those waves every entirely decrease to zero?
 
The short answer is 'no'. As mentioned, high-frequency EM won't even notice the walls, and low frequency such as radio will just slide on through as well. Wood is opaque only to visible and near-visible wavelengths.
 
For my money, if you catch visible light in a box, it's going to dissipate fairly regularly. In a classical sense, it will probably taper off to zero asymptotically; quantum mechanically, I guess, it may reach a point where (a) it just bounces around forever (no atoms in the wood absorb it because it's the wrong frequency or something) (b) it eventually is all gone (every photon eventually gets absorbed and emitted on the inside of the wood / outside of the box) (c) some crazy thing in between or (d) something completely and qualitatively different than anything I described above.

For my money... signal diminishes to zero, or so close to zero that you may as well assume it's zero. The point being, of course, is you can't carry light around in a box with you (maybe I'm wrong?)
 

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