Mirror on the Wall: Light & Reflections

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Discussion Overview

The discussion revolves around the theoretical scenario of two infinite planes of mirrors facing each other and the implications for light and reflections in that context. Participants explore the nature of reflection, the role of light, and the conditions necessary for reflection to occur.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions what the mirrors would reflect if they are infinite and facing each other, suggesting that light plays a crucial role.
  • Another participant proposes that if the mirrors are truly infinite, the only light present would be that which was "trapped" at their inception.
  • A different viewpoint states that with nothing in between the mirrors, there is nothing for them to reflect.
  • One participant expresses confusion about the question, indicating it feels like a brain teaser but is unsure of its deeper implications.
  • Another participant raises a question about the temperature of the mirrors, potentially implying that this could affect the scenario.
  • One participant asserts that mirrors reflect light based on the presence of light, noting that if there is no light, there will be nothing reflected, while also discussing factors that influence reflection, such as material properties and light dissipation.
  • Several participants emphasize the necessity of an observer in the scenario, suggesting that observation might influence the nature of reflection.

Areas of Agreement / Disagreement

Participants express differing views on the nature of reflection in the absence of light, with some asserting that nothing would be reflected while others suggest the presence of trapped light. The necessity of an observer is also a recurring theme, indicating a lack of consensus on its role in the scenario.

Contextual Notes

The discussion does not resolve the implications of infinite mirrors or the conditions under which reflections occur, leaving several assumptions and definitions open to interpretation.

HardDay'sNight
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If two planes of mirrors (infinite in all directions) were facing each other with nothing in between what would they reflect? How does light come into play in this?
 
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If they were truly infinite in all directions, then the only light between them would be that which was "trapped" when they came into existence.
 
Answer (whited out)

As there is nothing in between, there is nothing for them to reflect.
 
This question is odd, since it is a brain teaser I instinctively thought that there had to be something more to it... but I just can't see what the something could possibly be :/
 
Last edited:
How hot are the mirrors?
 
This doesn't seem like a brain teaser to me. It sounds like an optics question. And a pretty basic one at that.

Mirrors will reflect a certain degree of whatever light is shone at them. So, if there's no light, they'll reflect nothing. If there is light, they'll reflect that light. Depending on the mirror's material, they may not reflect various wavelengths of light (like, say, X-rays or radio waves), but they should certainly reflect most visible light. Eventually, the light will also dissipate, such that nothing as reflected, as each subsequent reflection will decrease the intensity of the light by a certain amount. The amount of dissipation probably depends on the material being used for reflection (usually aluminum in common mirrors), and the specific wavelength of the light. And possibly other factors like ambient temperature, pressure, glass covering, material purity, etc.

DaveE
 
But there must be an observer.
 
rootX said:
But there must be an observer.

There must also be a glass of milk!
 

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