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Thread: Speed of Light. Please HELP my argument

  1. #1 Speed of Light. Please HELP my argument 
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    Me and my friend are having a huge argument. Is the speed of light a scientific theory?

    He says, it is.

    I say, it's not, in a vacuum, ( the only legit way to test it) the speed will never ever change in a million years

    Thanks


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  3. #2  
    Genius Duck Dywyddyr's Avatar
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    We've measured the speed of light.
    That makes it an observation rather than a "theory".
    Speed of light - Wikipedia, the free encyclopedia


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  4. #3  
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    We observed, measured the speed of light. And then hypothesized that it is stable and could never change. I don't think there is a way to be sure that the speed of light won't change in a billion years.
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    How is it supposed to change in a billion years? Is this random speculation from your mind? You sound like my ignorant friend.
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  6. #5  
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    So is it a damn scientific theory? That means it can change? It will never always be the same in a vacuum? Jesus Christ you just made this argument much more heated with your out of your ass comment, feeding the fire of my ignorant friends tirade.
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  7. #6  
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    Quote Originally Posted by SHaRkNiT View Post
    So is it a damn scientific theory?
    You were already answered: the speed of light, c, is an observation. Your poll has no correct answers.
    Last edited by Chucknorium; May 18th, 2014 at 06:02 PM.
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  8. #7  
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    How the hell does my poll have no answers? So is it a Scientific theory? An observation is used in a scientific theory. So obviously it's not a theory. Right? How can you say that man please be more clear and specific
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  9. #8  
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    Quote Originally Posted by CaptainCuriosity View Post
    We observed, measured the speed of light. And then hypothesized that it is stable and could never change. I don't think there is a way to be sure that the speed of light won't change in a billion years.
    The problem is what you mean by "be sure". Philosophically speaking, science deals in "provisional truth", inasmuch as any theory is always subject to the possibility of being shown wrong or incomplete. Theories cannot be proved true, because however many observations you make that fit the theory, there could always be a new one, some time, under new conditions or whatever, that doesn't fit and thus causes the theory to be revised. This has happened many times in the history of science.

    The constancy of the speed of light is fundamental to a large and highly successful part of physics and as such is - for the time being - accepted by physicists.
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  10. #9  
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    If you were to ask "Can matter travel faster than the speed of light?" the answer would be "No." And that is part of a theory.
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  11. #10  
    Genius Duck Dywyddyr's Avatar
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    Quote Originally Posted by SHaRkNiT View Post
    So is it a damn scientific theory? That means it can change? It will never always be the same in a vacuum? Jesus Christ you just made this argument much more heated with your out of your ass comment, feeding the fire of my ignorant friends tirade.
    I'd suggest that your friend isn't the only ignorant one involved in this.
    For example YOU apparently have no idea what "theory" means in a scientific context.
    A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method, and repeatedly confirmed through observation and experimentation.

    The speed of light is an observed FACT.
    And facts get fed into theories.
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  12. #11  
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    Quote Originally Posted by SHaRkNiT View Post
    How the hell does my poll have no answers? So is it a Scientific theory? An observation is used in a scientific theory. So obviously it's not a theory. Right? How can you say that man please be more clear and specific
    Why don't you drop the "hell's" and the "damn's".
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  13. #12  
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    Okay, so it's not a theory? Right?
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  14. #13  
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by SHaRkNiT View Post
    So is it a damn scientific theory? That means it can change? It will never always be the same in a vacuum? Jesus Christ you just made this argument much more heated with your out of your ass comment, feeding the fire of my ignorant friends tirade.
    I'd suggest that your friend isn't the only ignorant one involved in this.
    For example YOU apparently have no idea what "theory" means in a scientific context.
    A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method, and repeatedly confirmed through observation and experimentation.

    The speed of light is an observed FACT.
    And facts get fed into theories.
    Although, to be fair, it is more than that, as Maxwell's equations imply it must be constant, don't they? If so, then the constancy of it is a prediction of a theory in physics as well as something that is observed to be the case.

    The speed itself is not a theory of course since, as you point out, a theory is an explanation and the speed of light - on its own - is obviously not an explanation.
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  15. #14  
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    Sorry, scientific theory
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  16. #15  
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    Quote Originally Posted by Chucknorium View Post
    Quote Originally Posted by SHaRkNiT View Post
    How the hell does my poll have no answers? So is it a Scientific theory? An observation is used in a scientific theory. So obviously it's not a theory. Right? How can you say that man please be more clear and specific
    Why don't you drop the "hell's" and the "damn's".

    Why don't you grow up?
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  17. #16  
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    Right because coming to a forum asking for help and behaving like a stroppy brat is so mature? Lose the attitude or go away.
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  18. #17  
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    How did I behave like a brat? Please leave my topic if you have nothing to offer but nagging and bullshitting. Don't like what I say then get out of here. I'm here to talk n discuss not have a random person waste my time and space by telling me what to say or not say. How ridiculous
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  19. #18  
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    Fine carry on, just don't be surprised when you are banned. Hopefully soon. Mind how you go.
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  20. #19  
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    Quote Originally Posted by SHaRkNiT View Post
    How did I behave like a brat? Please leave my topic if you have nothing to offer but nagging and bullshitting. Don't like what I say then get out of here. I'm here to talk n discuss not have a random person waste my time and space by telling me what to say or not say. How ridiculous
    By coming here and immediately swearing and abusing people who were trying to answer your peculiar question. Like the rest of us, you can only post here on the basis that you behave yourself in a civilised way. If you can't do that you will get chucked out by the moderators.

    Are you drunk, by any chance?
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  21. #20  
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    I don't mean any harm, I don't want to be told not to say damn or he'll. What a waste of space and time. I suppose I did unload on that guy who gave me an answer without backing it up, saying light might change in a billion years. I say misinformation is just as bad if not worse than a brat and childish attitude, and for that reply I do apologize, I am heated as HELL and it is hot here and me and my friends are at each others throats.
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  22. #21  
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    Can speed of light ever change in the future?
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  23. #22  
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    Quote Originally Posted by SHaRkNiT View Post
    Can speed of light ever change in the future?
    Absolutes shouldn't be used but I would say "No." But who knows what we may learn about the universe and physical laws in the future.
    Last edited by Chucknorium; May 18th, 2014 at 06:03 PM.
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  24. #23  
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    Quote Originally Posted by SHaRkNiT View Post
    I suppose I did unload on that guy who gave me an answer without backing it up, saying light might change in a billion years.
    Then you missed, entirely, his point.
    As he quite clearly stated "I don't think there is a way to be sure that the speed of light won't change" - i.e. we don't know for sure that it will remain constant.

    I say misinformation is just as bad if not worse than a brat and childish attitude
    Given your posts here you seem ill-equipped to discern "misinformation".
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  25. #24  
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    So it is a scientific theory? Sorry my friend just wants to know that specific question. We keep going back and forth
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  26. #25  
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    Quote Originally Posted by SHaRkNiT View Post
    So it is a scientific theory? Sorry my friend just wants to know that specific question. We keep going back and forth
    How would you answer someone that asked you "Is a 6-cyl engine an automobile?"

    Or more scientific: "Is red-shift of light a theory?" Answer: It is an observation that comes into play in theories.
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  27. #26  
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    My friend still says no, it's a scientific theory because the speed of light may possibly change someday. I really don't know what to say to him and all this trouble he's bringing me and having me direct to you
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  28. #27  
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    Quote Originally Posted by SHaRkNiT View Post
    So it is a scientific theory? Sorry my friend just wants to know that specific question. We keep going back and forth
    OK, if you only had two choices, yes or no, then "No". But it would be a qualified "No. It is an observation that is used in theories."
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  29. #28  
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    Quote Originally Posted by SHaRkNiT View Post
    So it is a scientific theory?
    Dear god.
    It's an observation!
    Theories are built on observations.
    The speed of light ITSELF is a FACT.
    There are theories based on, and around, that FACT.
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  30. #29  
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    Quote Originally Posted by SHaRkNiT View Post
    So is it a damn scientific theory? That means it can change? It will never always be the same in a vacuum? Jesus Christ you just made this argument much more heated with your out of your ass comment, feeding the fire of my ignorant friends tirade.
    You should probably review what a scientific theory is.

    Your incendiary language is not going to lead to productive conversation. A day off to think about it before coming back and hopefully displaying a bit more courtesy and civility needed to make you a valued member of this forum.
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  31. #30  
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    Here, let me try.

    The speed of light is an observation.

    The constancy of the speed of light is an AXIOM or POSTULATE.

    The speed of light is postulated to remain constant in all inertial frames of reference, in the theory of Special Relativity (a theory for which we have a large amount of experimental evidence). This means that all measurements made of the speed of light in inertial frames will show it to have the same value, regardless of the motion of the source of light relative to that frame.

    According to the postulate that the speed of light is constant, even if the speed of light were to change in the future, it would still be constant - it would still be measured by different frames as having the same value. But that value might be different from the value we measure today.

    The constancy of the speed of light between inertial frames (a postulate of Special Relativity), and a speed of light that changes over time, are separate issues.

    It is an axiom that the laws of physics do not change, over time.

    HOWEVER, we have good evidence that the speed of light has not changed in the past few billion years because a change in the speed of light would affect the fine structure constant, which affects other processes like nuclear reactions, and we have evidence from things like the Oklo natural nuclear fission reactor that this has not changed.

    So, we make the assumption, based on evidence, that the speed of light is not only constant between frames, but that it does not change over time either. Both are axioms or postulates.
    Last edited by SpeedFreek; May 18th, 2014 at 06:19 PM.
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  32. #31  
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    Where is Markus "the king of c" when you need him? I appreciate the frustration with the attitude being exhibited by the poster of this thread. I however am concerned with the lack of defense of c. From the day I began enjoying these discussions, the one thing I have gotten embedded into my cranium is c as a constant.
    If time and intergalactic travel could, by some chance change that, why would we even consider bb? The inability to support c as a constant even over time really makes me wonder.
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  33. #32  
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    Quote Originally Posted by SHaRkNiT View Post
    What a waste of space and time.
    Yup.

    /thread
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  34. #33  
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    Quote Originally Posted by keeseguy View Post
    Where is Markus "the king of c"
    Nothing against Markus, but you don't need more than a rudimentary understanding of physics to understand that "speed of light" is not a theory. The problem is an incorrect application of terms. The speed of light is NOT a theory in an of itself. It is an observation (as stated for the OP a half dozen times already) which plays a tremendous role in ACTUAL theories. As someone else stated, an engine is not a car. Nor is a wing a plane or a leaf a tree.

    The speed of light is considered a constant, but there is no way to prove that it will never change. The OP appears to be completely impervious to the rational and informative answers already given in this thread. There really isn't anything else to add.
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  35. #34  
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    Perhaps slightly off-topic, but ... this all reminds me of creationists who say "evolution is only a theory" and think that means something like it's only a hairs-breadth away from being "proven wrong".

    My advice to SHaRkNiT : step 1 is for both you and your friend to mutually agree on your usage of the term "scientific theory". (Hopefully - use the standard one, as described in this thread).
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  36. #35  
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    Notwithstanding that the OP seems to be a sockpuppet of a previously banned troll, there is a theory, by Magueijo, that claims that light was "faster" in the past. Google "Tired Light Theory". According to this theory, light speed is getting slower with time.
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  37. #36  
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    Quote Originally Posted by Flick Montana View Post
    There really isn't anything else to add.
    One thing that no one has so far stated is that since 1983 the definition of the metre implies that the speed of light in a vacuum is a defined constant of 299792458 ms–1.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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  38. #37  
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    does it consider distance traveled, or just time?
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  39. #38  
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    Quote Originally Posted by keeseguy View Post
    does it consider distance traveled, or just time?
    What do you mean? The metre is defined as the distance light in a vacuum travels in of a second.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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  40. #39  
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    Quote Originally Posted by keeseguy View Post
    does it consider distance traveled, or just time?
    It's unclear what "it" you're referring to, but if you mean "tired light" theories, the idea is that redshift is due to energy lost by light as it travels through space. It's an effort to eliminate universal expansion as an explanation for redshift.

    If, instead, you mean theories that postulate a non-constant c, some hypotheses allow for some variation with time in the fundamental "constants" of nature. So far, experiments tell us that the constants are constant (to thus-and-so error bars, etc. etc.).
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  41. #40  
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    Quote Originally Posted by SHaRkNiT View Post
    Me and my friend . . .
    Science by poll is not science.
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  42. #41  
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    Sorry KJW, need to learn to use quotes more often. My question was about tired light, thanks for answering all my inquiries, both of you.
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