How Small Can Mirrors Reflect in Recursive Reflection?

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Discussion Overview

The discussion centers around the concept of recursive reflection between two mirrors and explores the limits of image recognition as one zooms into the reflections. Participants consider the implications of light behavior, resolution, and the physical setup of mirrors in this context.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions at what point the image becomes unrecognizable when zooming into the reflection between two mirrors, suggesting a microscopical-sized reflection may exist.
  • Another participant proposes that the smallest recognizable image would be limited to the wavelength of light.
  • A different participant disagrees, arguing that a single spot at the wavelength of light cannot contain a complete image due to potential degradation of resolution or field of view.
  • Another contribution suggests that zooming in would not yield recursion but rather a close-up image of the viewing device or surroundings, raising concerns about the feasibility of the proposed experiment.
  • One participant introduces the concept of a Fabry-Perot optical resonator, explaining the conditions under which light would emerge amplified based on the proper frequencies of the resonator.
  • A later reply discusses the potential for significant tunneling of light through mirrors at separations near the wavelength of light, speculating on the relationship between the resolution of tunneled radiation and the initial image.

Areas of Agreement / Disagreement

Participants express differing views on the limits of image recognition in recursive reflection, with no consensus reached on the smallest size of recognizable images or the feasibility of the proposed experimental setup.

Contextual Notes

Participants note various assumptions about light behavior, resolution, and mirror configurations, which may influence the discussion but remain unresolved.

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If we have two mirrors, each one facing the other (producing what i'll describe as recursive reflection) then, supposing we could zoom into one of the mirrors as much as we'd like, then at what point would the image become unrecognizable. Would there be a microscopical-sized reflection of the other mirror? How small can/does it get?
 
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Depending on how we choose to look at light, it would be as small as the wavelength of light
 
Mattara said:
Depending on how we choose to look at light, it would be as small as the wavelength of light

I disagree.
There is no way that a single spot as small as a wavelenghth of light could contain an entire picture of its reflective ancestory under that condition.
Most likely, there would be a serious degredation of resoultion or field of view, or both.
 
Uh, you'd wouildn't get recursion if you zoomed in. You'd get a close-up image of the device, camera or head of whom/what-ever is doing the viewing.

So there's only two ways this could be set up:
-if your view angle was oblique, but that means eventually, your light path will slip off the side of the mirror and you'll simply be viewing a really zoomed in image of the laboratory wall.
- you put the reflective surface *in front* of your viewer. Which means you use a semi-silvered mirror, which means every bounce of the light loses brightness, which means after a few bounces, there's no light left to get through.

I am not sure your experiment is possible even in principle.
 
Last edited:
If put two mirrors parallel (at about .5 meter) you have a Fabry-Perot optical resonator. If the distance is less (about .5 cm) you may have a filter.

This device has its own proper frequencies so if one of them is not all reflecting (such as 99% of reflecting) the radiation only emerges from the cave if its frequency is equal (approx.) to one of the proper frequencies of the resonator.

The common use is in gas laser such as Ar-Ne or CO2. You put an amplification media inside the cave, and if the maximum of gain is very close to one of the proper frecuencies of the cave (in other case the radiation will not be amplified) then, the radiation emerges amplified and you have a cool laser€ :D
 
At a separation near the wavelength of the initial light, I believe that significant tunneling of higher wavelengths and lower amplitude through the mirror (one dimensional box) would occur. I guess that the image resolution of this tunneled radiation to that of the initial image would vary approximately as the squared ratio between initial light frequency and tunneled light frequency.
 

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