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Thread: Looking at doppler a different way.

  1. #1 Looking at doppler a different way. 
    Junior Member butchtroll's Avatar
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    What if time/space was changing at an accelerating rate?

    We could define time as a constant and space expanding or vice-verse.

    Now when we measure light from a distant source, we would be measuring light that originated at a past point in space/time and its wave length would retain the space/time aspects of the past, we would perceive this as a change in wavelength rather than a change in space/time.

    The layman's way of looking at this is that light reflected from objects is not expanding... our eyes are!

    When we look at an object, we are seeing it as it was in the past... it was smaller then.
    Last edited by butchtroll; 09-24-2013 at 04:14 PM. Reason: punctuation
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  2. #2  
    Senior Member Strange's Avatar
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    So you are talking about cosmological red-shift rather than Doppler effect? (Doppler is the change in pitch as a car passes you, for example.)

    It is true that you can choose a different set of coordinates where space is not expanding but objects are shrinking. This is just another way of describing the same thing and so is indistinguishable by any observations we can make. The usual convention is simpler and (for most people) more intuitive.
    You can do everything right, strictly according to procedure, on the ocean and it'll still kill you, but if you're a good navigator at least you'll know where you were when you died.
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  3. #3  
    Junior Member butchtroll's Avatar
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    The usual convention is what distorted the shape of the accelerating expansion discovered by these Nobel prize winners:
    http://www.nobelprize.org/nobel_priz...sprize2011.pdf
    Why should it have this shape instead of a conical shape? why should the expansion have slowed and then increased later?
    Conventional thinking is that the acceleration should be constant, but then of course conventional thinking says the universe must have a beginning!
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  4. #4  
    Senior Member Strange's Avatar
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    Quote Originally Posted by butchtroll View Post
    Conventional thinking is that the acceleration should be constant
    Conventional thinking is that the acceleration is what we observe.
    but then of course conventional thinking says the universe must have a beginning!
    No it doesn't.
    You can do everything right, strictly according to procedure, on the ocean and it'll still kill you, but if you're a good navigator at least you'll know where you were when you died.
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    Junior Member butchtroll's Avatar
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    So, which way do you swing currently... Big Bang or no Big Bang?
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  6. #6  
    KJW
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    Quote Originally Posted by butchtroll View Post
    What if time/space was changing at an accelerating rate?

    We could define time as a constant and space expanding or vice-verse.

    Now when we measure light from a distant source, we would be measuring light that originated at a past point in space/time and its wave length would retain the space/time aspects of the past, we would perceive this as a change in wavelength rather than a change in space/time.
    In the Friedmann-Lemaître-Robertson-Walker cosmological model, one can coordinate-transform the usual time-constant, expanding-space coordinate system to a coordinate system that manifests the conformally flat nature of the spacetime (both time and space expanding equally). This simplifies the equations of light-rays by putting them in the simple form.
    A tensor equation that is valid in any coordinate system is valid in every coordinate system.
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    Junior Member butchtroll's Avatar
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    Isn't it possible that what we see as a spectrum shift (to the red) is actually light that appears compressed because at an earlier point in expansion it was compressed? Perhaps this will help: look at a distant object, place your thumb so that it blots out the object, now are light waves expanding? Perhaps the object appears at the size it was in the past? I apologize if this is not clear, perhaps someone who gets it can provide a better example?
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  8. #8  
    Administrator Markus Hanke's Avatar
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    Quote Originally Posted by butchtroll View Post
    Isn't it possible that what we see as a spectrum shift (to the red) is actually light that appears compressed because at an earlier point in expansion it was compressed? Perhaps this will help: look at a distant object, place your thumb so that it blots out the object, now are light waves expanding? Perhaps the object appears at the size it was in the past? I apologize if this is not clear, perhaps someone who gets it can provide a better example?
    I am not sure what you mean by that.
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  9. #9  
    Senior Member Strange's Avatar
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    Quote Originally Posted by butchtroll View Post
    So, which way do you swing currently... Big Bang or no Big Bang?
    The big bang theory describes the evolution of the universe from an earlier hot, dense state. It is the best theory we have currently. (Is that what you mean?)

    Quote Originally Posted by butchtroll View Post
    Isn't it possible that what we see as a spectrum shift (to the red) is actually light that appears compressed because at an earlier point in expansion it was compressed?
    That is sort of what the standard description says: the observed red shift is due to the change in scale factor over time.

    It is worth noting that it isn't just a shift of the spectrum (as in Doppler shift) it is a more general time dilation; so we see a corresponding change in the time taken for other things such as the change in brightness of supernovas. The big bang theory also makes other predictions that match observation.
    Evidence for the Big Bang
    You can do everything right, strictly according to procedure, on the ocean and it'll still kill you, but if you're a good navigator at least you'll know where you were when you died.
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  10. #10  
    Junior Member butchtroll's Avatar
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    Quote Originally Posted by Markus Hanke View Post
    I am not sure what you mean by that.
    It may be better to say an earlier point in time, which by my theory is an earlier point in universal expansion. I will be elaborating in detail on my theories here:Primary constituent entities of the universe. - Physics Help Forum
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  11. #11  
    Senior Member MaxPayne's Avatar
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    Why should it have this shape instead of a conical shape? why should the expansion have slowed and then increased later?
    Thanks for the file
    I don't know for sure, but the expansion might have been slowed down due to formation of massive objects with mass.They might have tied down the expansion for a while but eventually their gravity was over powered by the expansion, drifting them away from each other.


    The layman's way of looking at this is that light reflected from objects is not expanding... our eyes are!
    Since photons are fundamental particles, they will not expand.But why red shift is happening?
    Also if a galaxy is accelerating towards us will our eyes shrink?
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  12. #12  
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    Quote Originally Posted by MaxPayne View Post
    Thanks for the file
    I don't know for sure, but the expansion might have been slowed down due to formation of massive objects with mass.They might have tied down the expansion for a while but eventually their gravity was over powered by the expansion, drifting them away from each other.
    Wouldn't this go against Newton's First Law?
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