Laser Light Passing Lane: Proton, Light Waves & Info

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Discussion Overview

The discussion revolves around the behavior of laser light and information packets when reflected off a moving mirror. Participants explore the implications of the mirror's speed, the nature of light and protons (or photons), and the potential for altering the order of transmitted signals. The conversation touches on theoretical aspects of light propagation, Doppler effects, and the fundamental principles of physics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question the clarity of the original setup, particularly regarding the direction of the mirror and the receiver of the signals.
  • There is a suggestion that bouncing light off a moving mirror cannot change the order of the light pulses, only their arrival times, due to the constant speed of light.
  • One participant raises a question about the possibility of secondary information overtaking initial transmissions, particularly in the context of blue shifts and the effects of moving mirrors.
  • Another participant proposes replacing mirrors with a reflective magnetic field, prompting further speculation.
  • Concerns are raised about using the speed of sound as a reference point, as it varies in different materials and is much slower than the speed of light.
  • Some participants emphasize that the speed of light remains constant and cannot be overtaken, regardless of reflections or Doppler shifts.

Areas of Agreement / Disagreement

Participants generally agree that the speed of light is constant and that the order of signals cannot be changed by reflections from a moving mirror. However, there remains disagreement and uncertainty regarding the implications of different setups and the effects of various factors on signal transmission.

Contextual Notes

Some limitations in the discussion include assumptions about the definitions of speed and direction, as well as the unresolved nature of how different setups might affect the transmission of light and information packets.

David Cate
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Here is the setup. We have a laser (supplement any type here) that constantly beams information packets in sequential order. If that beam was suddenly bounced off of a FORWARD moving mirror, traveling 7 times the speed of sound, would the protons, light waves and or information packets overtake the original set initially projected? ie. Would 1111 2222 3333 4444 5555 turn into 1111 2222 5555 4444 3333 ??
 
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It is not really clear to me what your setup looks like, which direction do you define as "forward" and who is receiving the signals? Typically, in one dimension, you will not be able to change the order of pulses by just bouncing off different mirrors regardless of how they move. You can just make them arrive with longer or shorter intervals in between just as you can red or blue shift the light.
 
Protons? Do you mean photons?

There is no way to overtake light in vacuum. I don't understand how your signal would bounce of a mirror that is slower than those photons, but all the mirror could do is change the frequency and direction of the light, not the speed.
 
David Cate said:
Here is the setup. We have a laser (supplement any type here) that constantly beams information packets in sequential order. If that beam was suddenly bounced off of a FORWARD moving mirror, traveling 7 times the speed of sound, would the protons, light waves and or information packets overtake the original set initially projected? ie. Would 1111 2222 3333 4444 5555 turn into 1111 2222 5555 4444 3333 ??
No, they would not over take the previous light since it all moves at the same speed.
 
Would secondary information ever overtake the first transmissions, even if mirrors were traveling toward the laser at a much faster speed? If a blue shift occurred, would it slow down the secondary packet transmission speed? I'm just find it difficult grasping a constant under these variables ... affecting both waves and particles. (see attachment)
optical frequency comb.png
 
mmm what if the mirrors were replaced with a reflective magnetic field ??
 
First off, the speed of sound is not a good reference as it would be different in different materials. In addition, the speed of sound is very slow compared to the speed of light, which means that the light would be red/blue shifted by a small amount only.

In fact, it is a relatively simple exercise to figure out that you cannot change the order of the signals in this way. All you need to do is to ask and answer the following questions: When does a given light pulse hit the mirror? Based on this, when does it reach the observer? What you need to apply is just basic kinematics and the fact that the speed of light is constant and equal to c.
 
The original poster's question has been answered.
 
David Cate said:
Would secondary information ever overtake the first transmissions, even if mirrors were traveling toward the laser at a much faster speed? If a blue shift occurred, would it slow down the secondary packet transmission speed? I'm just find it difficult grasping a constant under these variables ... affecting both waves and particles. (see attachment)View attachment 73369
I already answered this. No. The speed of light is c regardless of any reflection or Doppler shift.
 

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