Changing of one of the previous topics

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Discussion Overview

The discussion revolves around the hypothetical scenario of observing one's reflection in a mirror while traveling at the speed of light, c. Participants explore the implications of special relativity on this scenario and the nature of light and reflection at relativistic speeds.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests that at 0.99c, one would see their reflection due to the constancy of the speed of light in all inertial frames, but questions what happens at the speed of light, c.
  • Another participant asserts that traveling at the speed of light is impossible, referencing a cultural reference to emphasize this point.
  • A participant emphasizes the hypothetical nature of the question, asking what one would see in the mirror if traveling at light speed.
  • One reply states that the question is poorly defined within the framework of relativity and suggests that a specific alternative theory would be needed for a concrete answer.
  • Another participant expresses confusion about whether the question can only be answered if framed as traveling "close to the speed of light."
  • A further contribution discusses the idea of imagining an image being transmitted digitally, but clarifies that this does not equate to seeing oneself in the mirror while traveling at light speed.
  • One participant reiterates that light cannot interact with the mirror before reaching it, reinforcing the impossibility of the scenario as posed.
  • A participant mentions the principle "ex falso quod libet," indicating that one can derive any conclusion from a false premise.

Areas of Agreement / Disagreement

Participants generally agree that traveling at the speed of light is impossible, but there is no consensus on how to interpret the hypothetical scenario or what it implies about reflection and light interaction.

Contextual Notes

The discussion highlights limitations in defining scenarios that violate the principles of relativity, as well as the challenges in addressing hypothetical situations that fall outside established physical laws.

dasher
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in one of the previous topics, it was suggested that if one carries a mirror and travels at a speed of 0.99c, he will still see his own reflection in the mirror because the theory of special relativity states that the speed of light is constant in all inertial frames. However, what if i change this question a little and say that i am traveling at the speed of light, c? will i still see my image in the mirror? i doubt so since i think there wouldn't be any reflection of light then.
 
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dasher said:
in one of the previous topics, it was suggested that if one carries a mirror and travels at a speed of 0.99c, he will still see his own reflection in the mirror because the theory of special relativity states that the speed of light is constant in all inertial frames. However, what if i change this question a little and say that i am traveling at the speed of light, c? will i still see my image in the mirror? i doubt so since i think there wouldn't be any reflection of light then.

As has been said over and over again, you can't travel at the speed of light (only Freddy Mercury can...:smile:). It's impossible. Kiss that goodbye.
 
OOO said:
As has been said over and over again, you can't travel at the speed of light (only Freddy Mercury can...:smile:). It's impossible. Kiss that goodbye.
what i mean is "IF". if i do, what will i see in the mirror?
 
dasher said:
what i mean is "IF". if i do, what will i see in the mirror?
It's a poorly-defined question. Relativity doesn't allow it, so you'd have to outline a specific alternative theory in order to get a specific answer.
 
:confused: so does this mean that i can only answer the question if i leave it as "close to the speed of light"?
 
dasher said:
what i mean is "IF". if i do, what will i see in the mirror?

"IF" something false is true then anything is true. Ex falso quod libet.

But if you like to abuse your imagination then you may think of an image of you looking in the mirror. If that image is sent to some distant star by a digital transmission then most likely the bits representing the mirror will always have the same distance from the bits representing your eyes. But again, that's not you looking in the mirror at the speed of light, but an image of you looking in the mirror at the speed of light.
 
dasher said:
:confused: so does this mean that i can only answer the question if i leave it as "close to the speed of light"?

If you intend to know something about physics then the answer is definitely yes.
 
OOO said:
As has been said over and over again, you can't travel at the speed of light.
But this is not really important for the question, because it can easily be rephrased as follows. Seeing yourself in the mirror means that you can indirectly (i.e., via light) interact with the mirror without actually coming to the position of the mirror. So can light indirectly interact with the mirror before coming to the position of the mirror? The answer is - of course not, because in order to do that light should emit something that moves even faster, which is impossible.
 
I repeat: ex falso quodlibet. You can prove anything from falsity.
 

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