Solve the Mystery: What Does a Red Light Look Like?

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Discussion Overview

The discussion explores the perception of light from a hypothetical spherical red light source, focusing on how it would appear to the human eye in an isolated environment. It touches on concepts of vision, light propagation, and biological aspects of eye function.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether a spherical red light source would be perceived as a red ball surrounded by blackness, uniformly red, or red with decreasing intensity.
  • Another participant draws an analogy to stargazing, suggesting that bright lights are typically seen surrounded by darkness, particularly in areas with minimal light pollution.
  • A later reply proposes that the perception of "all red but in decreasing intensity" would only occur if there were reflective particles in the environment.
  • One participant raises a biological perspective, asking if light from a sphere would hit every part of the eye if no other light sources were present.
  • Another participant affirms that the presence of a lens in the eye is crucial for focusing light, implying that without it, vision would be blurred.
  • A participant expresses gratitude for the clarification regarding the role of the lens in vision.

Areas of Agreement / Disagreement

Participants express differing views on how light from a spherical source would be perceived, with no consensus reached on the specific visual outcome.

Contextual Notes

Assumptions about the environment, such as the presence of other light sources or reflective materials, are not fully explored, leaving some aspects of the discussion unresolved.

Fletcher
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Suppose there was a spherical red light source and that was the only thing that existed. Would your eye see a red ball surrounded by blackness, or would your whole vision be uniformly red, or would you see all red but in decreasing intensity?
 
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In case you haven't- When you look at the stars at night you see bright lights surrounded by blackness. (Works best far away from city lights- spend a night in the Utah desert some time- it's awesome!)

You would only see "all red but in decreasing intensity" if there were a cloud of something to reflect the light around the source.
 
Maybe my question is more biological but, wouldn't light from a sphere come out in every direction and thus hit every part of your eye, assuming there was absoluely no other source of light?
 
Yes, if your eye didn't have a lens on it to focus the light.
 
I had no notion of a lens (I just looked it up) and didn't understand why everything isn't a blur. Thanks.
 

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