How can you see light that is traveling away from the observer?

In summary: this cannot be true, as the amount of light energy reflected back would be far greater than a single photon.
  • #36
UltraPi1,

Open communication is the only way for us to evolve. If current theories are ALL correct, why hasn't unification happened? Something must change, perhaps only perspective. The mentors on this forum do not need their cage rattled so as to develop disdain for people who ask questions, however ignorant they might seem. The conversations that degrade into angry exchanges already have them at arms length. How much further until their existence is pointless?

Only a fool critisizes someone for helping others.


LPF
 
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  • #37
Originally posted by UltraPi1
It would seem Simon got the best of the two Mentors, for three pages of this crock is every bit as much the fault of the response. The best return for this thread would have been no response at all. Surely you could have left poor Simon in the dark on that desert with a salty taste in his mouth, but nooooooooooooooooooo! You had to drag yerselves down to that desert, and save him, or eat him alive ... whichever comes first :-). This in my opinion ... puts you in the same class as Simon, where clearly he got the best of you. :wink:



and i thought i was an elitist...
 
  • #38
I am not sure if I got Simon's question right (it is a little difficult to discern exactly what the question is) but if I did, you seem to misunderstand what he is asking.

He isn't asking why he can see the dot.
He is asking why he can see the dot the same regardless of what angle the light reflects off the surface and what angle he views it at.
Since the surface refects the light in a scattered pattern, his contention is that as the angle of approach, and the angle of the observer changes, so should the intensity of the reflected spot of light.

Is this right, Simon?
(See the poorly drawn attached image. By the way, that is a three-legged stool that guy on the right is standing on.)

It seems that Simon is saying that all 5 observers in this picture will see both reflected dots (assuming identical lasers) as not only having the same intensity and shape, but all 5 observers will see the dots as the same intensity and shape with respect to each other's point of view.
In other words, observer 1 will see two identical dots that are identical to the two dots that observers 2-5 will see.

What Simon is claiming is that since the dots are being reflected in many different directions by the intricate sand surface, each observer should have a different number of photons aimed directly at his/her eyes so each observer's impression of the intensity and shape of the dots (s)he sees should vary from the next observer's (of course, not taking into account physical differences in each observer, as if eack of those five positions were all specifically Simon himself).

Is that what you were trying to ask, Simon?

Click here for image

(edited to add the URL, because I couldn't see my attached image)
 

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  • #39
Where's my attached image?

I guess I will have to upload it and post a link.

Edited to say that I posted a link to the image in the above post.
 
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  • #40
Originally posted by 8LPF16
If current theories are ALL correct, why hasn't unification happened? Something must change, perhaps only perspective. The mentors on this forum do not need their cage rattled so as to develop disdain for people who ask questions, however ignorant they might seem.
[maybe out of context, but important, nonetheless] The question here of course is: how much? How much do our current theories need to change to unify them? Important question, clearly.

Though many on the TD forum would like us to believe the changes will be massive and sweeping, it just can't be that way. There may yet be some profound change in our understanding of the underlying mechanisms, but that will likely change very little about how the current theories work - because they do work. They work extremely well. Any new theory will obviously need to agree with the existing ones and the massive body of evidence that supports them.
 
  • #41
He is asking why he can see the dot the same regardless of what angle the light reflects off the surface and what angle he views it at.
Well, he doesn't. If he did, interior decorating using light would be useless. In reality, no material scatters light in a perfectly uniform fashion. Hence, for example, photographers can use white pieces of paper to provide soft lighting for a scene. And increasing the distance does diminish the intensity of the light, or reflected light. This effect is not very noticable on the small scales he talks about. The roughness of the surface simply makes it hard to notice. The shape of the dot also does change, but the small size of the dot makes it harder to see.

Then we somehow came to the classic symptoms of paranoic-narcissitic-arrogant-crackpotism.
 
  • #42
Then we somehow came to the classic symptoms of paranoic-narcissitic-arrogant-crackpotism

Isn't that contagious?

LPF
 
  • #43
Originally posted by FZ+
Well, he doesn't. If he did, interior decorating using light would be useless. In reality, no material scatters light in a perfectly uniform fashion.

Oh, I know.
I am not arguing that at all.
I know he was wrong in his basic assumptions.
I am just saying that I think that was his point/question, and he seemed to be getting agitated because people were not answering that question.

If he hasn't left for good, maybe he can clarify that.

Are you around?
 
<h2>1. How can light be seen if it is traveling away from the observer?</h2><p>Light is a form of electromagnetic radiation that travels in a straight line. When it reaches the observer's eyes, it stimulates the cells in the retina, which then sends electrical signals to the brain. This allows the brain to interpret the light and create an image, even if the light is traveling away from the observer.</p><h2>2. Why does light appear to be moving away from us?</h2><p>Light can appear to be moving away from us due to the Doppler effect. This is when the frequency of the light waves changes as the source of the light moves closer or further away from the observer. As the source moves away, the light waves are stretched, causing them to have a lower frequency and appear to be moving away.</p><h2>3. Can we see light that is moving at the speed of light?</h2><p>No, we cannot see light that is moving at the speed of light. This is because light travels at a constant speed of approximately 299,792,458 meters per second, which is too fast for our eyes to register. However, we can see the effects of light, such as objects that are illuminated by it or shadows created by it.</p><h2>4. How do we know that light is traveling away from us?</h2><p>We can determine the direction of light by using the principle of light propagation. Light always travels in a straight line, so if we observe the light coming from a specific direction, we can infer that it is traveling away from us in that direction.</p><h2>5. Can we see light that is traveling away from us in a vacuum?</h2><p>Yes, we can see light that is traveling away from us in a vacuum. In fact, light travels faster and farther in a vacuum compared to other mediums, which allows us to see objects that are very far away, such as stars and galaxies. This is because there is no interference or absorption of light in a vacuum, allowing it to travel uninterrupted.</p>

1. How can light be seen if it is traveling away from the observer?

Light is a form of electromagnetic radiation that travels in a straight line. When it reaches the observer's eyes, it stimulates the cells in the retina, which then sends electrical signals to the brain. This allows the brain to interpret the light and create an image, even if the light is traveling away from the observer.

2. Why does light appear to be moving away from us?

Light can appear to be moving away from us due to the Doppler effect. This is when the frequency of the light waves changes as the source of the light moves closer or further away from the observer. As the source moves away, the light waves are stretched, causing them to have a lower frequency and appear to be moving away.

3. Can we see light that is moving at the speed of light?

No, we cannot see light that is moving at the speed of light. This is because light travels at a constant speed of approximately 299,792,458 meters per second, which is too fast for our eyes to register. However, we can see the effects of light, such as objects that are illuminated by it or shadows created by it.

4. How do we know that light is traveling away from us?

We can determine the direction of light by using the principle of light propagation. Light always travels in a straight line, so if we observe the light coming from a specific direction, we can infer that it is traveling away from us in that direction.

5. Can we see light that is traveling away from us in a vacuum?

Yes, we can see light that is traveling away from us in a vacuum. In fact, light travels faster and farther in a vacuum compared to other mediums, which allows us to see objects that are very far away, such as stars and galaxies. This is because there is no interference or absorption of light in a vacuum, allowing it to travel uninterrupted.

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