A light speed gedanken

Discussion in 'Physics & Math' started by CANGAS, Apr 28, 2006.

  1. Pete It's not rocket surgery Registered Senior Member

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    Not correct, because A is moving with respect to B unless you use a rotating reference frame, complete with pseudo-forces such as coriolis.

    In A's SR inertial rest frame, B is moving at 2.6km/s.
    This is easy to see in the Earth center inertial frame: B's orbit speed in this frame is 3.07km/s, and A's speed is 0.46km/s.
     
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  3. 2inquisitive The Devil is in the details Registered Senior Member

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    Pete, when you use the Earth centered inertial frame, you are using the the same frame as the ether frame.
     
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  5. Pete It's not rocket surgery Registered Senior Member

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    2inquisitive, I'm answering your question. It would be polite if you would answer mine.

    If a photon leaves B, bounces off A, and returns to B, what shape is its path?


    The speed of the photon isn't the question - it's the direction. The direction the photon is emitted depends on the velocity of the source. I don't know why this is such a balking point for you. Why would it not be affected?

    I really don't think you've thought this through. Have you tried drawing a diagram?
    The experimental facts are:
    • The incoming beam is not parallel with the outgoing beam in the Earth frame.
    • The incoming beam is parallel with the outgoing beam in the satellite frame
    Draw a diagram from the Earth point of view. The path of the beam has a 'v' shape.

    Now draw a diagram from the satellite point of view. The path of the beam is straight back and forth.

    I can draw the diagrams for you if you're unable.
     
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  7. Pete It's not rocket surgery Registered Senior Member

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    You can give it whatever label you like, 2inquisitive, it makes no difference. I can use any inertial frame at all and get the same result.
     
  8. 2inquisitive The Devil is in the details Registered Senior Member

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    I did answer your question, Pete. Perhaps you missed my answer.
     
  9. 2inquisitive The Devil is in the details Registered Senior Member

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    I think it is time to end this discussion. Either you can't understand my hypothesis because of your dependence on the diagrams stored in your mind, or you are deliberately avoiding the issue. Thanks anyway, Pete, I knew this would be the outcome, an impasse.
     
  10. Pete It's not rocket surgery Registered Senior Member

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    But it didn't answer the question.
    If A and B are both moving through the ether, and a photon travels from B to A and back again, what path does the photon trace?

    You seem to be asserting that it does not trace a v-shaped path... but I really just can't see how it could trace anything else. If the photon retraces its original path, then how can it return to B?

    Maybe I'm just ignorant or inflexible, but I really want to understand what you're thinking.
     
  11. Pete It's not rocket surgery Registered Senior Member

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    You haven't answered this question, either.
    Our thought experiment discussion was exactly that - a thought experiment. A thought experiment can be a test of logical internal consistency, but nothing more, unless its tested by a real experiment.

    So, what experimental result would indicate to you that your hypothesis is false? It's not a hard question. All you have to do is propose an experiment, predict the result according to your hypothesis, and state that if the result is anything else then your hypothesis would be false.

    Ideally, the result should be quantitative (numeric), different to that of competing theories such as SR, and correspond to a real experiment we can look up or perform ourselves.
     
  12. Pete It's not rocket surgery Registered Senior Member

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    If you want to draw some diagrams and email them to me, I'll put them on a website for you if you like.

    Please Register or Log in to view the hidden image!

     
    Last edited: Jun 3, 2006
  13. 2inquisitive The Devil is in the details Registered Senior Member

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    Pete, why do you think they have to 'point ahead' to hit the geostationary satellite? Why do you think they need to alter the configuration of the retroreflectors to redirect the return beam to hit the ground station? If they don't the photon will miss both A and B because they have moved while the photon traces the straight back and forth path. Both A and B move while the photon is in flight. By pointing ahead and redirecting the return path, the photon does travel a 'v' path, but not unless these alterations are made.
     
  14. Pete It's not rocket surgery Registered Senior Member

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    That's not the same situation, remember? The satellite's velocity is not the same as the ground station's velocity.
     
    Last edited: Jun 3, 2006
  15. Pete It's not rocket surgery Registered Senior Member

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    The ground station must point ahead because the satellite is moving in the ground station's inertial rest frame.

    The satellite must alter the return beam for the same reason. If it didn't, the beam would be deflected forward by the satellite's motion in the ground station's rest frame.

    Now, according to your hypothesis, the amount that the return beam needs to be altered would be calculated from the speed that the ground station is moving through the ether and how far away it is. The speed of the satellite with respect to the ground station would be irrelevant.

    According to special relativity, the amount that the return beam needs to be altered would be calculated from the speed that the satellite has with respect to the ground station and how far away it is.

    Look it up, and you'll find that the special relativity calculation is the one that is used successfully.
     
  16. 2inquisitive The Devil is in the details Registered Senior Member

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    Pete,
    Sorry, I went to eat. No, that is not according to my hypothesis. According to my hypothesis, the ground station is not moving through the ether. It is an ether drag hypothesis, remember? But,as one moves further from the Earth's surface, the ether is 'dragged' less and less. The geostationary satellite is above the altitude that most of the 'frame dragging' (Lense-Thirring) effects are encountered. So, for the lower part of the photon's journey, it moves in a straight line away from the ground station, moving with the ether and directly away from the surface of the Earth. As the photon moves higher in the ether, it begins to fall behind a line drawn from the ground station to the satellite. The ether does not move at the same rate throughout the universe, it is dragged by mass and gravity. In my hypothesis, gravity does not travel at the speed of light. It is analogous to the ether, almost stationary, but dragged by rotating mass. A gravitational wave is a disturbance that moves through both the gravitational field and the ether. In my hypothesis, a gravitational field and the ether are the same thing, with EM waves and gravitational waves that move through the field. The density of the ether decreases with the inverse square ratio, the same as a gravitational field. The gravitational field is not moving away from the Earth at the speed of light, but gravitational waves move through the gravitational field at 'c'. In my hypothesis, a gravitational field is kind of like the atmosphere, except extending farther, and both EM waves and gravitational waves move through the 'atmosphere'. A rotating gravitational field 'drags' massive objects with it to some extent, and also alters the straight-line propagation of light as the light moves through the field. The light from a distant star would travel in a straight line toward Earth, then be dragged slightly by the rotating ether/gravitational field of the Earth. Did you realize aberration of starlight still occurs when the observer is directly between the star and the center of the Earth? Think of the star directly overhead just like a geostationary satellite may be directly overhead. Aberration of light occurs in both situations, just not on as massive a scale as the aberration due to Earth's orbital motion around the sun because the velocity is not as great.
     
  17. Pete It's not rocket surgery Registered Senior Member

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    You said earlier that the Earth center inertial frame was the ether frame. It appears that you meant that the ECEF frame is the ether frame at the Earth's surface, and something different at geostationary height. That's OK - I'm glad that we're getting some definition to your hypothesis.

    I need more detail. How is the ether's movement determined at the geostationary satellite's height? How is it affected (if at all) by the Earth, the Earth's rotation, the Moon, the Sun, and the satellite itself?

    Is your hypothesis based on general relativity? If not, then why would the Lens-Thirring effect (a prediction of GR) be relevant? As predicted by GR, it is orders of magnitudes too small to be relevant to sending signals to a geostationary satellite. The ether dragging in your hypothesis seems to be something quite different.

    Why would I think otherwise?

    I'm glad we agree on these observations.
     
  18. Pete It's not rocket surgery Registered Senior Member

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    The curved paths of outgoing and incoming light has interesting implications for the aberration of starlight.

    As the Earth moves through the ether, light from a star will approach it at angle. But, as the starlight enters the dragged ether zone, it will be bent to follow Earth.

    If the ether is stationary on Earth's surface, you will find that the end result is that the angles cancel out, and that there should be no observed aberration of starlight.
     
  19. CANGAS Registered Senior Member

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    You must remember this, as time goes by.

    Pete has his own personal reasons for upholding some variation of Special Relativity, whether it makes sense or not.

    EM, also known as light, flies differently in a gas, such as atmospheric air, than it does in a vacuum. In air, or other medium, light speed is influenced by the speed of the medium. See Fizeau Experiments with light swimming through moving water. An observer on Earth must be careful to take the effect of the air into account when contemplating the apparent flight of light.
     
  20. Pete It's not rocket surgery Registered Senior Member

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    Well done, CANGAS. If the discussion doesn't go your way, you can always insinuate hidden agendas. You'd make a great politician.

    Completely correct. See Fresnel's coefficient of drag, and what it predicts for stellar aberration and Michelson-Morley.
     
  21. CANGAS Registered Senior Member

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    I have been learning about doing agendas from a master; Pete himself.
     
  22. 2inquisitive The Devil is in the details Registered Senior Member

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    No, the Earth will approach the lightpath at an angle. Stop thinking like a dyslectic.
    Dependes on what you mean by 'bent to follow Earth'. The starlight was not emitted in Earth's ether field, and it will not curve 'straight down' when it enters it, only slightly 'bent' like it is when passing any other ether field between the star and Earth, such as the sun. But Earth's gravity, and thus the 'ether field', is much less dense than the sun's.
    What 'angles cancel out'? The starlight is only 'bent' in one direction as it enters Earth's gravitational (ether) field.
     
  23. 2inquisitive The Devil is in the details Registered Senior Member

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    Pete, you may have not figured it out, but my 'ether drag' hypothesis is pretty much the same as the 'curved spacetime' of General Relativity. I am calling the 'curved spacetime' a gravitational ether field. The ether field distorts the same way as spacetime, in the presence of mass, and the ether field is 'dragged' the same way as spacetime by rotating mass. If no massive object were present, it would be almost stationary except for the expansion of the universe. Unlike GR's spacetime, my ether field decreases in density as the universe expands. The volume of the universe since the big bang is increasing, but the amount of the ether stays the same, decreasing in density to fill the larger volume due to the expansion. The density of the ether field also increases as one moves closer to large mass, just as spacetime is 'warped' by mass. A rotating galaxy also 'drags' the ether around with it, causing the galaxy to resemble more of a rotating disc as the stars on the perimeter of the galaxy try to move in concert with the stars nearer the center. In a galaxy, the mass is more evenly distributed than it is in our solar system, orbiting not so much a 'center' of mass like the solar system's planets orbit the sun, but more as a unit or disc. The stars in a galaxy are themselves dragged around by the rotating ether 'sphere' they are enclosed within. The Shapiro effect is caused by light passing through the denser ether around mass, or within the galaxy itself. From a distant observer's viewpoint, light slows as it transits the ether. From the viewpoint of someone inside the ether, they would measure the speed of light as always. The speed of light and the rate at which atomic clocks beat slow due to the change in the permittivity and permeability of 'spacetime', the properties of the gravitational ether itself in my hypothesis. I know my hypothesis is difficult to understand because it explains what you already 'know' in a different manner. I cannot refer you to any other 'theory' that works the same as mine because I did not copy my hypothesis from any other theory. It is closest to General Relativity in concept, but obviously different in interpretation. I am my own 'crackpot', I didn't copy my interpretation from any other site, but based it on experimental evidence as I interpreted the evidence. My interpretation was a model for all the little 'pieces' to fit together. I know you do not think it is consistent, but it is. You just haven't grasped the hypothesis yet, and I doubt you or anyone else is willing to take the time to understand what I am trying to convey. It sounds like gobbly-gook to you, so I just point out some things where my 'predictions' or explainations differ from mainstream theory.
     

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