Between two mirrors. Real experiment.

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    Experiment Mirrors
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Discussion Overview

The discussion revolves around two experiments involving reflections and light behavior in mirrors and reflective spheres. Participants explore the nature of images formed by flat mirrors and the implications of a perfectly reflective sphere containing a light source. The conversation touches on theoretical concepts, observational outcomes, and potential experimental setups.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • One participant proposes an experiment with two parallel mirrors and a light source, suggesting that it produces an infinite line of images due to repeated reflections.
  • Another participant counters that the images fade out due to losses at each reflection, and that the perspective of the images changes with distance.
  • A different experiment is introduced involving a perfect reflective sphere with a light bulb at its center, raising questions about the visual experience and thermal effects for an observer inside.
  • Concerns are raised about how light can "burn out" in such a scenario, with suggestions that energy remains trapped in the light bulb, potentially leading to overheating.
  • Participants discuss the mechanics of light reflection in mirrors, debating the visibility of multiple images and the conditions under which they can be observed.
  • Some participants express uncertainty about the explanations provided, particularly regarding the behavior of light and the formation of images in relation to mirror surfaces.
  • There is a discussion about the distance of images from the object in relation to a single mirror, with some agreeing that the image appears at a distance of 2r from the object, while others question the relevance of this for flat mirrors.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement on various points, particularly regarding the nature of images formed by mirrors and the behavior of light in reflective environments. No consensus is reached on the implications of the experiments or the explanations of light behavior.

Contextual Notes

Participants note limitations in their discussions, such as assumptions about the ideal conditions of reflections and the definitions of terms like "letting light in." The conversation remains open-ended with unresolved questions about the experiments proposed.

  • #31
Olias,
I'm not getting your point at all. Can you try again?
Olias said:
This is the basis of a posting from the original PF of some years ago"Quantum-Relativistic Reflections".
Those must have been wild times! :smile:
Take your example, but this time have yourself in directly front of a mirror, you observe yourelf in the "mirror-frame". Now comes along a quick-fire artist(like ones at court proceedings), who stands at an angle, and about 2mtrs next to you, he observes and draws the image he see's upon the mirror-frame.
I don't know what you mean by "mirror-frame".
So the artist draws something on the surface of the mirror? I assume he draws an outline of the image he sees from his vantage point? (So that when he's at his original position, it overlaps the image he sees perfectly?)
Now he shows you the drawn image that he 'see's', both debate as to the 'Real' image upon the mirror surface, you have argue the case because you are standing directly in front of the mirror. and see your reflection, which is difinately upon the mirror surface, you can confirm this by observation.
I'm getting lost now. What's the debate about? The "image" I see (of myself) is a virtual image located behind the mirror surface. That's the "same" image that the artist viewed from a different angle, and then outlined--for some reason I don't know--on the mirror. (The images are not really the "same"--both I and the artist see different light.)
Now the real interesting thing is that the second observer see's a totally different image upon the mirror surface, verified by his "Quick-fire" sketch, at the mirror, 'upon its surface', we now have to overlapping images!
I have no idea what you mean by overlapping images on the mirror surface. Or are you talking about overlapping drawings on the mirror surface?
Now enters a 100 quick-fire artists who all take up different locations and "draw-what-they-see" of mirror surface images, whilst you still remain 1mtr in front of the mirror looking at your 'Real' image.

So now there are 101 images supported on the mirror-surface, each image occurs relative to the observer and their position, and each image must be located on the surface of the ONE-MIRROR. The question now is, for the person standing directly in front of the mirror, how many quick-fire artists does it take before the image of the person starts to degrade due to the number of "overlapping" images upon a single surface?
So are you actually saying that the more people there are looking into the mirror, the more "degraded" my reflection should get? That somehow the images "overlap", whatever that means. (The drawings will of course overlap.)
Simplified, is there a maximum number of different locations away from the one directly in front?..and will an observer looking at his/her mirrored reflection contain information from any of the other observers surface images.

Is there multiple 'overlapping' occurring for multiple observers, if yes then some of the image on the reflected mirror-surface, must contain "bits" of information that is not from your observation frame.
I'm really not getting your point.
 
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  • #32
Ok, the virtual images of any reflected light coming from the mirror surface relays information to anyone 'looking' at the mirror, this is how we can 'see' reflections, as you state
Doc Al said:
No surprise at all--if you know what it means. Light reflects from the plane mirror as if it is coming from the virtual images in the mirror. There is a string of repeating images in the mirror, acting as virtual objects. Wherever one image would block another, from an observer's vantage point, they do--just like with real objects..

If you (A) stands directly in front of a mirror, you see your reflection, a virtual image on the surface of the mirror, obvious! If whilst you are standing in front of the mirror, another person(B) who stands 2 metres to your left, looks into the same mirror he/she will not see YOUR image, they will see a different image, just as the first person will not see what B see's obvious!

Person A remains in front of mirror, and a vast number of people position themselves around the room, all looking into the same mirror, there is information being relayed to all observers from a single mirror, is there a limit to the amount of information a single mirror can relay?..before causing some interference to person A's reflection?

Do you agree that an infinite number of observers using a single mirror, all see separate 'virtual' images intersect from and are relayed by the mirror surface?

Simple question, you stand in front of mirror observing your reflection, your partner stands away to your left, looks into mirror and describes what he/she see's, you describe what you see(your reflection because of your position directly in front), which one of you has the correct observational description?

I presume a debate would follow something like this, person A states, what I see is a reflection of myself inside the mirror-frame.

Person B, what I see is the reflection of a picture on the wall opposite to where Iam standing.

Person A to person B, point to where this image is upon the mirror surface. Person B moves towards the mirror with his/her finger pointing into the mirror, Person A now contends, I still see my image even though you are up close to the mirror with your finger pointing at the reflected image ..how so?
 
  • #33
From the post # 30
So what distinction between an object and its image in a mirror?
The real object can be submitted as {x, y, z, t}
The image of object is {-x, y, z}
Here x – the component of dimensions which perpendicular to a surface of a mirror.
A conclusion:
The image of object in a mirror is the pure spatial essence since has only three spatial dimensions instead of four at real object.
Absence of the fourth dimension (time) does not allow actions inside such the space. It is enclosed in the real spacetime, though does not occupy it.
 
  • #34
mirror, mirror on the wall...

Olias said:
If you (A) stands directly in front of a mirror, you see your reflection, a virtual image on the surface of the mirror, obvious! If whilst you are standing in front of the mirror, another person(B) who stands 2 metres to your left, looks into the same mirror he/she will not see YOUR image, they will see a different image, just as the first person will not see what B see's obvious!
A simpler way to look at it: Light from me hits the mirror at all points creating a single virtual image--visible from any vantage point--on the other side of the mirror. The image is not on the surface of the mirror. The reflected light that allows anyone to see the image (from different perspective) is always there, whether or not there is an observer to see it.
Person A remains in front of mirror, and a vast number of people position themselves around the room, all looking into the same mirror, there is information being relayed to all observers from a single mirror, is there a limit to the amount of information a single mirror can relay?..before causing some interference to person A's reflection?
Once again, you seem to be saying that the number of people viewing this virtual image somehow interferes with the light that person A sees and thus degrades the image? Are you serious? What possible effect could the additional observers have on the image in the mirror? You are speaking as if the observers somehow create the image, rather than merely observe the existing image.
Do you agree that an infinite number of observers using a single mirror, all see separate 'virtual' images intersect from and are relayed by the mirror surface?
No. A better way to say it is that all observe the "same" image, but using different light. The mirror creates a single virtual image, viewable by many.
Simple question, you stand in front of mirror observing your reflection, your partner stands away to your left, looks into mirror and describes what he/she see's, you describe what you see(your reflection because of your position directly in front), which one of you has the correct observational description?
That's a silly question. Like saying: Which is your real side, the left or the right? All perspectives are equally "correct". Each will describe "the same" image from their own perspective.
I presume a debate would follow something like this, person A states, what I see is a reflection of myself inside the mirror-frame.

Person B, what I see is the reflection of a picture on the wall opposite to where Iam standing.

Person A to person B, point to where this image is upon the mirror surface. Person B moves towards the mirror with his/her finger pointing into the mirror, Person A now contends, I still see my image even though you are up close to the mirror with your finger pointing at the reflected image ..how so?
I can't imagine any sane people having such a debate or being confused by what they see in a plane mirror. :smile: Is there some deep philosophical issue in this that I am missing?
 
  • #35
Michael F. Dmitriyev said:
I see the main question in this problem as :
- what distinction between an object and its image in a mirror?
In that case, the question has a very simple answer. The object exists, the image doesn't. That's why it's called an imaginary image and not a real image (which is created by convex lenses in some cases).
 
  • #36
Chen said:
In that case, the question has a very simple answer. The object exists, the image doesn't. That's why it's called an imaginary image and not a real image (which is created by convex lenses in some cases).
Are you sure this image does not exist without observer?
 
  • #37
I see the main question in this problem as :
- what distinction between an object and its image in a mirror?
Chen said:
In that case, the question has a very simple answer. The object exists, the image doesn't. That's why it's called an imaginary image and not a real image (which is created by convex lenses in some cases).
Be careful here - when dealing with optics, there is such a thing as a "real" and "virtual" image. Obviously, none of the images are the object itself though (thats why they are called "images"). Yes, the problem is one of definitions: Dmitri, you need to use the accepted definitions here or you can't comunicate your point.

http://dept.physics.upenn.edu/courses/gladney/phys151/lectures/lecture_apr_14_2003.shtml

Simply put, a real image is one projected on a screen and a virtual one appears to float in space.
 
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  • #38
Isn't there research being done to create a crystal that traps light? This idea is inspired by the cell structure of some kind of butterfly. It has very unusual optical properties. It amazed scientists because it was so complex.

I don't remember the details, you could try a google search.
 
  • #39
russ_watters said:
Be careful here - when dealing with optics, there is such a thing as a "real" and "virtual" image. Obviously, none of the images are the object itself though (thats why they are called "images"). Yes, the problem is one of definitions: Dmitri, you need to use the accepted definitions here or you can't comunicate your point.

http://dept.physics.upenn.edu/courses/gladney/phys151/lectures/lecture_apr_14_2003.shtml

Simply put, a real image is one projected on a screen and a virtual one appears to float in space.
I have described this difference at post # 33. It define WHY it is happen.
 
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  • #40
Chen makes a good point: An image is not real. The brain reconstructs this information from visual information. It is tricked. Other senses, e.g. touch, confirm that there is no image there. This BTW is true whether in optics the image is classified as "real" or "virtual". That is optics jargon and defines the word "real" differently.

MD wants to think of the image as existing in some other dimension. If that's helpful, fine. But this "existence" will have no other real implications besides that which is known from the usual optical explanations. So scientifically I find it a useless complication, and lance it with Occam. Nevertheless, it still has the power to entertain as in Lewis Carroll's "Through the Looking Glass".
 
  • #41
Originally Posted by Doc Al
A simpler way to look at it: Light from me hits the mirror at all points creating a single virtual image--visible from any vantage point--on the other side of the mirror. The image is not on the surface of the mirror. The reflected light that allows anyone to see the image (from different perspective) is always there, whether or not there is an observer to see it.

If SOMETHING exist whether or not there is an observer to see it, then this SOMETHING is REAL. Is it not so?
 
  • #42
Michael F. Dmitriyev said:
If SOMETHING exist whether or not there is an observer to see it, then this SOMETHING is REAL. Is it not so?
That sounds reasonable to me. In this example, what is real is the light that reflects from the mirror, which exists even if there is no observer to see it. (The image is virtual however.)
 
  • #43
krab said:
MD wants to think of the image as existing in some other dimension. If that's helpful, fine. But this "existence" will have no other real implications besides that which is known from the usual optical explanations. So scientifically I find it a useless complication, and lance it with Occam. Nevertheless, it still has the power to entertain as in Lewis Carroll's "Through the Looking Glass".

No, it is not an other dimension. This is the space without time. Replacement of a sign at one of spatial dimension results in exception of time:
{x, y, z, t}-->mirror--> {-x, y, z}
It is for a case with a single mirror.
Restoration of an initial sign results in restoration of time.
For a case with two parallel mirrors:
{x, y, z, t}->mirror1->{-x, y, z}->mirror2->{2x, y, z, t}->mirror1->{-2x, y, z}->mirror2 {4x, y, z, t} … etc.
Does this the process not the process of generation of space and time?
According to BB theory the universe has arisen from one singular point.
There may be this principle underlies expansion of the universe – generation of spacetime between two mirrors?
 
  • #44
By the way, my scale of light frequencies contains two mirror point. Is it a casual coincidence?
 

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