Understanding the Problem of Sumultaneity: Exploring the Dual Nature of Light

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In summary, the conversation discusses the possibility of a photon being in more than one place at once and the concept of simultaneity in relation to relativity. It is explained that the position of a photon is dependent on the reference frame and that different observers will measure different positions due to the time delay of relativity. The concept of cosmic time and position is also mentioned, with the understanding that relativity emphasizes the validity of each point of view.
  • #1
keepitmoving
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i don`t mean to be beating a dead horse but if every observer measures the speed of light to be C, doesn`t that make for the possibility of a given photon being in more than one place at once? I realize there can be a problem of sumultaneity which i don`t understand.
 
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  • #2


How are you getting the conclusion that a photon could be in more than one place at once? It can't, but I'm not sure how best to explain why unless you present your reasoning.
 
  • #3


I think what the OP is trying to say is if you're a photon going at the speed of light then light will travel away from you at the speed of light and so maybe the photon will travel faster than c?

Anyways, this isn't true due to relativity. If you're in the photon's reference, light will travel away from you at c. However, if you are an observer, you'll just see the photon going at c. The photon isn't in multiple places, it's just dependent on reference.
 
  • #4


keepitmoving said:
photon being in more than one place at once? I realize there can be a problem of simultaneity which i don`t understand.
There is no absolute "at once" for all observers. Simultaneity is relative. I guess that is your problem, but you have to describe your reasoning more accurately.
 
  • #5


bucher said:
in the photon's reference
This concept doesn't really make sense. See my posts in this thread for an explanation.

I think you're right about what the OP is thinking.
 
  • #6


i know i`m on the simple side but here goes - if a moving emitter sends a photon out and the photon moves at c away from the moving emitter such that the photon is always at c x time distance from the moving emitter, then that photon has a position at any instant. If another observer is moving in the opposite direction from the moving emitter and he also measures that same photon, then his c x time from his position to the photon would yield a different position for the photon. They`re both using c as the speed and using the same time so that should yield different positions for the photon. I must be haywire here. Sorry. Your help is appreciated.
 
  • #7


Well, since the emitter and the observer are going at different speeds relative to each other then they would measure different positions due to the time delay of relativity. If the emitter and the observer waited 1 second, then that one second would be different in either reference frame since they are moving at different speeds relative to one another.

Though this difference may be extremely small, they are using this time to find a position of a photon going at c. If one was to factor in the time delay with respect to the other's movements, then both would measure the same position of the photon.

I should note that this is without regard to the application of the Heisenberg Uncertainty Principle and the ability to measure a photon going away from you.
 
  • #8


keepitmoving said:
i know i`m on the simple side but here goes - if a moving emitter sends a photon out and the photon moves at c away from the moving emitter such that the photon is always at c x time distance from the moving emitter, then that photon has a position at any instant. If another observer is moving in the opposite direction from the moving emitter and he also measures that same photon, then his c x time from his position to the photon would yield a different position for the photon. They`re both using c as the speed and using the same time so that should yield different positions for the photon. I must be haywire here. Sorry. Your help is appreciated.

Measuring the speed of light means measuring speed.
Speed is defined as distance divided by time.
Time is passing at different rates in the two frames of reference experienced by the two moving observers. A second in one frame is longer than a second in the other, thus, the photon is measured as being farther from the emitter.
 
  • #9


keepitmoving said:
i know i`m on the simple side but here goes - if a moving emitter sends a photon out and the photon moves at c away from the moving emitter such that the photon is always at c x time distance from the moving emitter
That's true in the frame of the emitter, using that frame's distance and time measurements.
, then that photon has a position at any instant.
OK.
If another observer is moving in the opposite direction from the moving emitter and he also measures that same photon, then his c x time from his position to the photon would yield a different position for the photon.
No, the same photon has a single position. What's different are the coordinates of that position. That second observer will measure the photon's distance from him using his own distance and time measurements.
They`re both using c as the speed and using the same time so that should yield different positions for the photon.
No. Same position, just differently described.
 
  • #10


thank you much for your help.
Another question is - how does cosmic time and cosmic position figure in. It seems to me that relativity emphasizes each point of view as being valid but isn`t there a cosmic point of view and time?
 

FAQ: Understanding the Problem of Sumultaneity: Exploring the Dual Nature of Light

What is the problem of simultaneity?

The problem of simultaneity refers to the concept that two events happening at the same time may appear differently to different observers. This is due to the fact that the speed of light is constant, and as a result, the perception of time and space can vary for different observers.

How does this relate to the dual nature of light?

The dual nature of light refers to its ability to behave as both a wave and a particle. This duality is what causes the problem of simultaneity, as the perception of light as a wave or a particle can affect the way events are perceived by different observers.

What is the significance of understanding this problem?

Understanding the problem of simultaneity is crucial in many areas of science, particularly in the fields of physics and astronomy. It helps us to accurately interpret and measure the behavior of light and other phenomena, and can also lead to advancements in technology and our understanding of the universe.

How have scientists approached this problem?

Scientists have used various theories and experiments to try and understand the problem of simultaneity. This includes Einstein's theory of relativity, which explains how the perception of time and space can be affected by the speed of light, and the use of high-tech equipment to measure and observe light and its behavior.

What are some real-world applications of understanding the problem of simultaneity?

Understanding the problem of simultaneity has led to the development of technologies such as GPS systems, which rely on the accurate measurement of time and space. It has also played a crucial role in the development of quantum mechanics and has implications for the study of black holes and other phenomena in the universe.

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