Do we see multiple images in mirror?

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Discussion Overview

The discussion revolves around the question of whether multiple images of a person can be seen in a mirror due to reflections from both the mirror and surrounding objects, particularly clothing and walls. Participants explore the theoretical implications of light reflection and scattering, as well as the conditions under which multiple images might be perceived.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that while theoretically multiple images could be seen, practical factors such as light absorption by clothing and scattering effects prevent these images from being noticeable.
  • One participant argues that clothing scatters light, which blurs any potential reflective image, making it indistinguishable from the primary reflection.
  • Another participant suggests that additional light from scattered reflections may enhance the brightness of the primary image but does not create new images.
  • There is a hypothetical scenario presented where a mirror is placed on the chest, suggesting that this could lead to an infinite regression of images if positioned correctly.
  • Participants discuss the effects of white walls in a room and whether they would contribute to seeing multiple images, concluding that while they reflect light, they do so diffusely and do not create additional images.
  • One participant speculates about the potential for variable phase reflections creating interference patterns, while another counters that interference patterns require coherent light sources and would not occur with incoherent reflections.
  • It is noted that the front of the eye may reflect an image of oneself, but this would be a secondary image without interference fringes.

Areas of Agreement / Disagreement

Participants generally agree that while multiple images could theoretically exist, practical limitations such as scattering and absorption prevent them from being perceived. However, there is disagreement regarding the specifics of how reflections and interference patterns work, particularly in relation to coherent versus incoherent light.

Contextual Notes

Participants acknowledge various assumptions about the nature of light reflection and scattering, as well as the conditions under which images might be perceived. The discussion remains open to interpretation based on different scenarios and conditions.

leonstavros
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When we look at a mirror we see our image but the light that reaches our eyes also reflects off our bodies back to the mirror again and back to our eyes. Do we see multiple images of our self but somehow ignore all but the primary reflection?
 
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I would say theoretical yes, but NO for 2 reasons:
1 . the amount of absorption of light from clothing far out weighs any reflection - clothing is just not shiny.
2. If a ray of light from the mirror does hit your eye and is reflected, the angle of incidence = angle of reflection so only a very tiny amount of light would be at an angle sufficient so that the ray would be reflected back to the mirror and then back to your pupil - ie the reflected image would be something in between the size of your pupil and your iris, and again very faint, if not, completely unnoticable. due to absortion again.
 
Clothing reflects light (which is why you can see it in the first place, assuming the clothing isn't acting as a black body), but you don't see a reflective image because the clothing scatters the light it reflects, destroying any potential image with an extreme blurring effect. If the clothing approximated a mirror, then you could see an image reflected off that clothing, either directly or if viewing an image from a mirror.
 
The extra light scattered off your clothing from your image in the mirror simply adds a tiny bit to the brightness of the image. It doesn't create a new image.

If you were to hang a mirror on your chest, and keep it parallel to the other mirror, then you would see an infinite regression of multiple images in the image of that mirror. I see something like this in a restaurant where I often eat, that has mirrors on walls facing each other, with my seat in between.
 
What if you're in a room with a mirror and the walls painted white and you're also clothed in white? would you still see a single image on the mirror? I would guess yes although there would be a whole bunch of reflections in the room.
 
Yes, if all the other walls are white, they would reflect the light, but only diffusely, so that they would not create additional images. The image of the wall in the mirror just looks bright, but you don't see an additional image in the wall.
 
chrisbaird said:
Yes, if all the other walls are white, they would reflect the light, but only diffusely, so that they would not create additional images. The image of the wall in the mirror just looks bright, but you don't see an additional image in the wall.

I know I'm beating this thing to death but I keep thinking of scenarios such as sitting in the middle of the white room with the mirror in front of me thinking about all those variable phase reflections of the original image creating variable interference patterns as they add or subtract on my retina. What do you think?
 
No, you only get an interference pattern through a superposition of two or more coherent beams that are offset in some way. You don't get an interference pattern from a superposition of incoherent beams. All the random phase differences on average end up canceling out in non-coherent superpostions so that you get a sum of scalar sum of powers instead of a vector sum of fields. If you shine the beams from two different, isolated lasers at the same spot on the wall, you will not get an interference pattern. You have to lock the lasers together, or use one beam from one laser and split it into two beams that than interfere with each other (such as a Michelson interferometer).

The front of your eye is specularly reflective, so you may be able to see and image of yourself in your eyes in the mirror if you look really close, but it will just be a secondary image. There won't be interference fringes or anything.
 

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